JP2000333004A - Image copying system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system which substantially speeds up the printing speed of an image whose similarity with a specified image is small and can prevent the copying of the specified image by controlling color image data stored in a storage part so whether it is formed in an image forming part or not based on the detection result of a specified image detection part. SOLUTION: Color image data received by a scanner interface 91 is outputted to a feature value extraction part 93. The feature value extraction part 93 extracts feature value for detecting whether a specified image whose copying is inhibited is included in color image data or not. A CPU 98 decides whether the specified image exists in the inputted color image data or not based on the extracted feature value in three stages of temporary decision, secondary decision and final decision, for example. In the system, the color image data of a page memory 94 is outputted through an engine interface 95 and is immediately printed in an image forming part 2A when the specified image is decided to be not contained in the image which is read in the temporary decision.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus such as a color image scanner and an image forming apparatus such as a color laser beam printer, and for forming a color image based on color image data output from the image reading apparatus. The present invention relates to an image copying system for printing by an apparatus.

[0002]

2. Description of the Related Art In recent years, with the dramatic improvement in the performance of color scanners and color printers as input / output devices of color copiers and personal computers, it has become possible to easily obtain high-precision color copies. I have. In particular, since a color copying machine is the simplest means for obtaining a color copy, it has a function of recognizing a specific image such as a bill which is originally prohibited from being copied, and prohibiting or restricting the copying.

Here, the schematic operation of a conventional image copying system such as a color copying machine will be described.

In a color copying machine, in the process of obtaining a color copy, an original is scanned using an image reading device such as a flatbed type color image scanner. The original is scanned a plurality of times for each color (more strictly, in one scan, for example, all three primary color signals of R, G, and B are captured, and image processing such as well-known color correction is performed). Later, it is output as monochromatic image data), and finally C (cyan) and M which are the three primary colors of printing
(Magenta) and Y (yellow). Further, K (black), which is difficult to reproduce by printing with the three primary colors of the printing, may be added. An image recording unit (image forming unit) that scans the color image data converted into the three primary colors for printing on a recording medium such as paper, for example, converts the monochromatic color image data output from the color image scanner. Visualization is performed according to each color signal. At this time, the number of scans in the image scanner is determined according to the number of colors to be superimposed. For example, if an image is formed in three colors (C, M, Y), the number of scans of a single color in the image scanner is three, and if an image is formed in four colors (C, M, Y, K). The number of times of scanning of a single color by the image scanner is four.

In a color copying machine, a specific image, such as a banknote, which is originally prohibited from being copied, contained in a document is detected in parallel while performing a plurality of scans corresponding to the printing colors. . Therefore, when the specific image is detected, the process of forming the image is also in progress. Therefore, in order to prevent the specific image from being copied, a process such as solid-filling a specific color component on the normally formed image before the detection of the specific document is performed, and Hide the image. Since this concealment process is performed in order to prevent copying of a copy-prohibited material such as a bill, the toner concentration to be superimposed becomes high, and the color material is wasted. Furthermore, in the above-described method, if a non-specific image is erroneously determined to be a specific image in the unlikely event that the original is not prohibited by law, it cannot be used as a copy. There is a disadvantage that.

[0006] Recently, color image scanners and color printers have been replaced by, for example, SCSI (Small Comm.).
An image copying system that can easily create a copy by connecting via an interface such as a computer system (Putter System Interface) has also been announced. Comparing this system with a color copier, color copiers do not have page memory, but these systems have at least one page of image memory (using the memory of the controller built into the color printer). The color image data scanned by the color image scanner is temporarily stored in the memory, and the color image data in the memory is subjected to predetermined image processing in accordance with the characteristics of the color printer and user instructions. The difference is that printing is performed by a color printer. In terms of how to use the memory, there is a method of binarizing the image after image processing and storing it in the memory. In any case, by providing a memory for storing color image data, a color image scanner can be obtained by scanning. It is only necessary to have a function of transferring the color image data to the memory, and there is no need to be aware of the image forming process of the color printer. This eliminates the need to output color image data in a format that depends on the image forming process of the color printer, and many color image scanners used in this type of system use RG in one scan.
Most output B color image data.

When a specific image detecting function is installed in such an image copying system, a process of forming an image by scanning a document and a process of detecting a specific image can be processed independently. That is, it is possible to detect the specific image in parallel while storing the color image data output from the color image scanner in the memory, and it is also possible to detect the specific image based on the color image data once stored in the memory. is there.

However, in this image copying system, the image forming process can only be started after the color image data to be printed is stored in the memory, so that there is a time lag between image reading and image formation. As a result, the throughput from image reading to image formation is reduced, and in addition to this, the actual start of image formation is further delayed by the time required to check for the presence or absence of a specific image. As a countermeasure, the color image data is stored in the memory and the specific image is detected in parallel.Image formation is started immediately when the color image data is stored in the memory, and the color image data is detected when the specific image is detected. It is also possible to intervene in the printer imaging process. However, with this method, similar to the above-described color copying machine, for example, it is necessary to take measures such as solidly superimposing a toner of a specific color. However, the problem that a copy is useless cannot be solved.

[0009]

As described above, in the conventional image copying system, a concealment process is performed to prevent copying of a prohibited copy such as a bill, so that the toner concentration to be superimposed becomes high, and the color material is increased. In the event that a non-specific image is erroneously determined to be a specific image, copying of the original is not prohibited by law. Nevertheless, it has a problem that it cannot be used as a copy.

In this image copying system, it is required that the printing speed of an image having a small similarity to the specific image can be substantially increased, and that the specific image can be prevented from being duplicated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image copying system capable of substantially increasing the printing speed of an image having low similarity to a specific image and preventing duplication of the specific image. And

[0012]

In order to solve this problem, an image copying system according to the present invention has a reading controller, and scans an original under the control of the reading controller to output color image data. An image forming apparatus comprising: a reading device; a copying controller; and an image forming unit, wherein the image forming device inputs color image data from the image reading device based on control of the copying controller and forms a color image in the image forming unit. In the copying system, the copying controller includes a storage unit that stores the color image data input from the image reading device, and includes in the input color image data a plurality of steps including at least two steps of provisional determination and final determination. A specific image detecting unit for detecting a specific image to be detected, and storing in a storage unit based on a detection result of the specific image detecting unit. The color image data has a structure and a control section for controlling whether or not to form the image forming section.

Thus, an image copying system which can substantially increase the printing speed of an image having low similarity to the specific image and can prevent the specific image from being duplicated is obtained.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image copying system according to a first aspect of the present invention has an image reading device, which has a reading controller and scans an original to output color image data under the control of the reading controller. And an image forming apparatus having a copying controller and an image forming unit, and inputting color image data from an image reading device under control of the copying controller to form a color image in the image forming unit. The copying controller includes a storage unit that stores the color image data input from the image reading device, and a specific image included in the input color image data based on a plurality of steps including at least two steps of a provisional determination and a final determination. And a color image stored in the storage unit based on a detection result of the specific image detection unit. It is obtained by the fact that a control unit that controls whether to form over data to the image forming unit.

With this configuration, the specific image detecting section can determine stepwise whether or not the image is a specific image. Therefore, when it is determined in the temporary determination that the image is not a specific image, formation of a color image can be started immediately. The printing speed of an image having low similarity to the specific image can be substantially increased, and the duplication of the specific image can be prevented based on accurate final determination.

According to a second aspect of the present invention, in the image copying system according to the first aspect, the control unit comprises:
When one or more color image data is stored in the storage unit, an instruction signal for instructing the image forming unit to start image formation is output to the image forming unit, and the specific image detecting unit determines that the specific image is present in the temporary determination. In this case, the instruction signal is canceled and the hold signal is output.

With this configuration, the image forming unit is started immediately when the color image data for one image or more is stored in the storage unit, thereby recording the image when it is determined by the temporary determination that the image is not the specific image. Can be sped up, and, if an image having a high similarity to the specific image is detected in the tentative determination after the image forming unit is activated, a signal for suspending image formation is output to output the image forming unit. There is an effect that the operation can be stopped to prevent duplication of the specific image.

According to a third aspect of the present invention, in the image copying system according to the second aspect, the control unit comprises:
When the specific image detection unit determines that there is no specific image in the final determination, the hold signal is canceled and the instruction signal is output again.

With this configuration, the image forming section has an effect that the image formation can be continued.

According to a fourth aspect of the present invention, in the image copying system according to the second aspect, the specific image detecting section is configured to execute a process before the image forming section starts visualization processing based on color image data. This is to output the result of the tentative determination.

With this configuration, by preventing an image from being formed (in a visible form) before the result of the provisional determination is obtained, it is possible to prevent wasteful consumption of coloring materials and the like.

According to a fifth aspect of the present invention, there is provided an image copying system having a reading controller, which scans an original under the control of the reading controller to output color image data, a copying controller, and an image forming apparatus. And an image forming apparatus for inputting color image data from an image reading device based on control of a copying controller to form a color image in an image forming unit. A storage unit that stores at least one image of color image data input from the image reading device, and a specification that detects a specific image included in the input color image data by at least two-stage determination including temporary determination and final determination The image detection unit and the color image data stored in the storage unit based on the detection result of the specific image detection unit. By processing the data, it is obtained by the fact that a control unit to form a color image based on color image data obtained by processing the image forming unit.

With this configuration, when it is determined that the image is a specific image, the color image data is processed, and the duplication of the specific image is prevented.

According to a sixth aspect of the present invention, in the image copying system according to the fifth aspect, the control unit comprises:
When the specific image detection unit determines that there is a specific image in the final determination, predetermined processing is performed on the color image data stored in the storage unit.

This configuration has the effect that the duplication of a specific image can be prevented without using special image processing hardware.

According to a seventh aspect of the present invention, in the image copying system according to the sixth aspect, the control unit comprises:
When the specific image detection unit determines that there is a specific image in the final determination, the specific image detection unit performs a scaling process on the color image data stored in the storage unit.

With this configuration, it is possible to prevent duplication of the specific image, and to avoid a situation where the duplicate becomes useless even if the non-specific image is erroneously determined to be the specific image. It has the action of:

An image copying system according to an eighth aspect of the present invention includes an image reading apparatus having a reading controller, which scans an original under the control of the reading controller to output color image data, a copying controller, and an image forming apparatus. And an image forming apparatus for inputting color image data from an image reading device under control of a copying controller to form a color image in an image forming unit. A copy image controller that detects a specific image included in the read color image data, the copying controller stores a color image data input from the image reading device, and a detection unit that detects the specific image detection unit. Based on the result, it is controlled whether or not to cause the image forming unit to form the color image data stored in the storage unit. Is obtained by the fact that a control unit for.

According to this configuration, since the specific image can be compressed and transmitted from the image reading device to the image forming device, the transmission efficiency can be improved, and whether or not the color image is formed in the image forming portion can be determined. Since the determination is made by the high-speed control unit of the copying controller, it is possible to prevent counterfeiting of bills and the like without increasing the price.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS.

(Embodiment 1) FIG. 1 is a configuration diagram showing a general (common to the conventional and the present embodiments) image copying systems.

In FIG. 1, reference numeral 1 denotes an image reading device;
Denotes an image forming apparatus, and 3 denotes a cable. The image reading device 1 reads a document and outputs digital color image data. The image forming apparatus 2 forms a color image based on image data transferred from the outside. A copying controller (not shown, which will be described later in detail) is stored inside the image forming apparatus 2. The copying controller processes color image data output from the image reading apparatus 1 and prints the image data. In addition to generating data and controlling the overall operation of the image forming apparatus 2, the image reading apparatus 1
It is detected whether or not the color image data input from the printer includes a specific image such as a bill prohibited from being copied. The cable 3 includes an image reading device 1 and an image forming device 2
Are connected to each other, and image data and commands are bidirectionally communicated between the devices by the cable 3. In the present embodiment, the image reading device 1 and the copying controller built in the image forming device 2 communicate with each other by SCSI, and the image forming device 2 issues a plurality of commands to the image reading device 1. Then, image data is input from the image reading device 1, and an image is formed based on the input image data.

Next, the configuration and operation of the image reading apparatus 1 will be described.

FIG. 2 is a schematic sectional view showing the image reading apparatus 1 constituting the image copying system of FIG.

In FIG. 2, reference numeral 1 denotes an image reading device;
Is a document glass on which a document to be read is placed, 7 is a carriage for scanning and reading an image on the document by moving relative to the document, 8 is a stepping motor as a drive source for driving the carriage 7, and 9 is a drive Pulley, 10 is a timing belt, 11 is a belt, 12 is a driven pulley,
Reference numeral 13 denotes a document placed on the document glass 6, reference numeral 14 denotes a document cover, reference numeral 15 denotes a support, and reference numeral 16 denotes a reference acquisition position. The carriage 7 is supported by a support member such as a shaft and a rail (not shown), and the movement direction is restricted to one direction. The power generated by the drive source 8 is transmitted to the drive pulley 9 by the timing belt 10. The belt 11 is stretched between the driving pulley 9 and the driven pulley 12, and moves the carriage 7 in the direction d1 and the opposite direction with the rotation of the driving pulley 9. The document 13 is read line by line by the movement of the carriage 7. The document cover 14 is supported by a support unit 15 so as to be openable and closable. Further, a white reference plate is attached on the document glass at the reference acquisition position 16. po1 is the home position of the carriage 7, and when the image reading apparatus 1 is on standby, the carriage 7 is always located at the home position po1.

FIG. 3 shows the carriage 7 of the image reading apparatus 1.
It is a schematic sectional drawing which shows the internal structure of.

In FIG. 3, reference numeral 6 denotes an original glass similar to that of FIG. 2, reference numeral 7 denotes a carriage similar to that of FIG. 2, reference numeral 13 denotes an original similar to that of FIG. 2, reference numeral 17 denotes a lamp for irradiating the original, and reference numeral 18 denotes substantially image reading. Aperture for specifying position, 19a, 19b
Denotes a reflection mirror that reflects light reflected from the document 13, 20 denotes an image sensor that converts optical information into an electric signal, and 21 denotes an imaging lens that forms an image of the document surface on the image sensor 20. The image sensor 20 is configured by three line sensor arrays each having R (red), G (green), and B (blue) filters, and reads the original 13 while separating the original 13 into three primary colors of RGB in line units. . The image sensor 20 is fixed inside the carriage 7 and reads optical information reflected from the document 13 and reduced and imaged by the reflection mirrors 19a and 19b and the imaging lens 21 in a one-to-one relationship with the document surface. Note that, in the present embodiment, the image sensor 20 is 600 dpi (dot per inch) with respect to the original surface.
Optical resolution.

The image reading apparatus 1 configured as described above
2 will be described with reference to FIGS.

When the power of the image reading apparatus 1 is turned on, the carriage 7 returns to the home position po1 regardless of the initial position. Thereafter, the aperture 18 moves to the reference acquisition position 16 immediately below the reference plate, and the lamp 1
7 is turned on, the reference plate is actually read, the amplification factor for the analog signal output from the image sensor 20 is determined, and the black and white level is corrected (shading correction). After that, it returns to the home position po1 again, and enters a standby state.

The reading resolution, reading range, and the like are set by the image forming apparatus 2 (strictly, a copying controller (not shown) built in the image forming apparatus 2 issues commands and the like, which will be described in detail later). Thereafter, when a command to read the document is issued, the image reading device 1
Turns on the lamp 17 and rotates the driving source 8 to transmit the driving force to the carriage 7 via the timing belt 10, the driving pulley 9, the belt 11, and the driven pulley 12,
The carriage 7 is moved at a predetermined speed in the direction d1. This direction d1 is called a sub-scanning direction. Immediately before the carriage 7 reaches the head of the area corresponding to the reading range set from the image forming apparatus 2, the driving speed is changed from the image forming apparatus 2 to a speed corresponding to a predetermined reading resolution, and the original glass 6 is set. The reading of the original 13 placed thereon is started. The original 13 is illuminated by the lamp 17 through the original glass 6, and the reflected light from the original 12 is reflected by the reflection mirrors 19 a and 19 b, reduced and imaged on the image sensor 20 by the imaging lens 21, and converted into an electric signal. Is converted. When the reading operation for the specified reading range is completed, the carriage 7 is moved in the direction opposite to the direction d1, and returned to the home position po1.

Next, a reading controller of the image reading apparatus 1 shown in FIG. 1 will be described.

FIG. 4 is a block diagram showing a reading controller of the image reading apparatus 1.

In FIG. 4, reference numeral 2 denotes an image forming apparatus similar to that of FIG. 1, 8 denotes a stepping motor, 20 denotes an image sensor similar to that of FIG. 3, 24 denotes an amplifier / A / D converter, 25 denotes a shading correction section, and 26 denotes a shading correction section. Is a line correction unit, 27 is a resolution conversion unit, 28 is a color processing unit, 29 is a buffer, 30 is an interface unit, 32 is a motor control unit, 33 is a CPU,
34 is a system bus.

In the reading controller configured as described above, the image sensor 20 is composed of the three line sensor arrays as described above, and outputs analog image information of each of R, G, and B in units of lines. amplifier·
The A / D converter 24 amplifies the analog image information output from the image sensor 20 with a predetermined gain, and converts the amplified analog signal into a digital signal by the A / D converter. Shading correction unit 25
Normalizes an input digital image signal to a previously acquired dynamic range of black and white.
The line correction unit 26 corrects the difference between the line sensor array positions of the respective colors that are spaced apart in the sub-scanning direction.
This is equivalent to reading each of the G and B sensor arrays at the same original position (line). The resolution conversion unit 27 converts the resolution of the image data output from the line correction unit 26 based on the parameters specified by the image forming device 2. The color processing unit 28 enables a vivid color reproduction by reducing the influence of unnecessary absorption bands on the spectral spectrum existing in the color filters on the line sensor array. The buffer 29 temporarily stores the image data processed in the above process. This is a means for absorbing a difference in communication speed with the outside and outputting image data to an external device at a higher speed. With the interface unit 30, the image reading device 1 inputs a reading parameter from the image forming device 2 and outputs image data to the image forming device 2.
These reading parameters and image data are more accurately transmitted to and received from a copying controller built in the image forming apparatus 2. This specific description will be described later.

In this embodiment, the image reading apparatus 1 and the image forming apparatus 2 are connected by SCSI with respect to the interface unit 30, and the image reading apparatus 1 transmits image data to the image forming apparatus 2 via SCSI. In addition to the output, read parameters such as a read range and a read resolution are input from the image forming apparatus 2.
Needless to say, the interface may be a bidirectional interface other than SCSI, and for example, IEEE1394 or the like may be applied. The interface is, for example, TCP / I
For example, the image reading apparatus 1 may be connected to a network, and may be connected to the image forming apparatus 2 via the network. The motor control unit 32 outputs a drive signal (more precisely, an excitation signal for the stepping motor) to the stepping motor 8 that moves the carriage 7 of the image reading device 1. The CPU 33 controls an operation sequence of the image reading device 1 and the like. The CPU 33 controls each component via a system bus 34.

Next, the mechanical configuration of the image forming apparatus 2 will be described.

FIG. 5 is a configuration diagram showing a mechanical configuration of the image forming apparatus 2 constituting the image copying system of FIG.

The image forming apparatus shown in FIG. 5 is an image forming apparatus to which an electrophotographic technique is applied, in particular, a latent image formed on a photosensitive member by a laser beam or the like is developed by a developing device of each color, and the developed single color is developed. This is an image forming apparatus of a so-called intermediate transfer body type, in which an image is temporarily transferred onto a medium called an intermediate transfer body and synthesized, and the combined image on the intermediate transfer body is collectively transferred to paper.

In FIG. 5, reference numeral 51 denotes a loop belt-shaped photosensitive member. The photoconductor 51 includes three photoconductor transport rollers 5.
2, 53, and 54, and are rotated in the drive direction d2 by a drive motor (not shown). Reference numeral 56 denotes a photoconductor position detection mark, one of which is disposed at an end of the photoconductor 51. Reference numeral 57 denotes a photoconductor position detection sensor that detects the photoconductor position detection mark 56. Photoconductor 51 is at seam 5
8, the seam 58 must be avoided when forming an image. At this time, the output of the photoconductor position detection sensor 57 is referred to. The charger 59, the exposure optical system 60, the black (K),
Developing units 61K, 61Y, 61M, 61C for each color of yellow (Y), magenta (M), and cyan (C), a neutralizer before intermediate transfer 62, an intermediate transfer roller 63, a photoconductor cleaning device 64, and a neutralizer 65 are provided. Have been.

The charger 59 is composed of a charged wire made of a tungsten wire or the like, a shield plate made of a metal plate, a grid plate or the like (not shown). When a high negative voltage is applied to the charged wire, the charged wire performs corona discharge. Wake up. When a voltage of, for example, -700 V is applied to the grid plate, the surface of the photoconductor 51 is uniformly charged to a negative potential of about -700 V.

The exposure optical system 60 includes a laser driving device, a polygon mirror, a lens system, a polygon mirror driving motor (scanner motor) and the like (not shown), and forms an electrostatic latent image on the charged photosensitive member 51. I do. 66 is an exposure optical system 6
Exposure light beam emitted from 0. The exposure light beam 66 is obtained by driving a laser diode (not shown) with a binarized pulse output corresponding to the image data, and forms an electrostatic latent image on the photoconductor 51 corresponding to the image data of a specific color.

Each of the developing units 61K, 61Y, 61M, 61C
Respectively store black, yellow, magenta, and cyan toners. Each color developing device has sleeve rollers 67K, 67Y, 67M, 67C using conductive rubber or the like.
When the toner is rotated in the forward direction, the thinned toner is supplied from the inside of the developing device to the surface of the sleeve roller. When the toner is thinned, the toner is negatively charged by friction. Negative voltage (development bias) applied to sleeve roller for development of each color
Is applied, and while rotating the sleeve roller, the motors (not shown) corresponding to the color separation / contact cams 68K, 68Y, 68M, 68C are driven, and the selected developing device, for example, the black developing device 61K is moved in the d4 direction. This operation is performed by urging the sleeve roller 67 </ b> K to contact the photoconductor 51.

The surface potential (bright potential) of the photosensitive member 51 at the portion where the latent image is formed has risen to around -50 to -100 V. When a negative potential of about -300 V is applied to the sleeve roller, the photosensitive drum 51 is exposed to light. An electric field is generated from the body 51 toward the sleeve roller. As a result, a Coulomb force acts on the negatively charged toner on the sleeve roller in the direction opposite to the electric field, that is, in the direction of the photoconductor 51, and the toner adheres to the latent image portion formed on the photoconductor 51. On the other hand, since the surface potential (dark potential) of the photoconductor 51 in the portion where the latent image is not formed is -700 V, the electric field is generated from the sleeve roller toward the photoconductor 51 even when the developing bias is applied, so that the toner is not exposed. Does not adhere to body 51. The above-described development process is generally called a negative-positive process or a reversal development because toner (that is, black) adheres to a portion irradiated with light (that is, white).

The pre-intermediate transfer static eliminator 62 is a device in which a plurality of red LEDs are arranged on a line, and the toner image formed on the photoreceptor 51 is transferred to an intermediate transfer member 69 which is a medium for synthesizing each color image.
Immediately before the transfer, the surface of the photoconductor 51 is neutralized. The pre-transfer static elimination is performed when the toner image is transferred to the intermediate transfer member 69 and no toner is present on the photoconductor 51.
This has the effect of preventing the reverse transfer of the toner image to the photoconductor 51.

The intermediate transfer roller 63 is a metal roller in the vicinity of the photosensitive member support roller 53 and in contact with the inside of the intermediate transfer member 69.
And it is arranged facing. Since a part of the layer forming the photoconductor 51 is grounded, when a positive voltage is applied to the intermediate transfer roller 63, an electric field is generated from the intermediate transfer roller 63 toward the photoconductor 51. For this reason, Coulomb force acts on the negatively charged toner on the photoconductor 51 in the direction of the intermediate transfer member 69, and the toner is transferred to the intermediate transfer member 69.

The photosensitive member cleaning device 64 includes the photosensitive member 5
1, and is disposed to face the photoconductor support roller 54, and removes residual toner remaining on the photoconductor 51 after the transfer of the intermediate transfer body 69 from the photoconductor 51.

The static eliminator 65 has a plurality of red LEDs arranged on a line, and removes a residual potential on the photoconductor 51.

The intermediate transfer member 69 is a seamless loop belt made of a conductive resin or the like, and is a medium for forming a full-color image by synthesizing a single-color image. The intermediate transfer member 69 is supported by three transport rollers 70, 71, and 72, and is rotated in the direction d3 by the same drive motor (not shown) as the photosensitive member 51. Reference numeral 73 denotes a mark for detecting the position of the intermediate transfer member, and a plurality of marks, eight in this embodiment, are arranged at the end of the intermediate transfer member 69. Reference numeral 74 denotes an intermediate transfer member position detection sensor that detects the intermediate transfer member position detection mark 73. When forming an image, one of the plurality of intermediate transfer body position detecting marks 73 is selected and used as a reference for the image forming position. Photoconductor 5 as described above
1 has a joint 58, but by selecting an optimum mark from a plurality of intermediate transfer member position detecting marks 73, it is possible to shorten the time until printout is completed while avoiding the joint 58. Become.

Around the intermediate transfer member 69, a pre-transfer charger 75, a density sensor 76, a paper transfer roller 77, and an intermediate transfer member cleaning device 78 are arranged in the rotation direction indicated by d3.

The pre-transfer charger 75 is a corotron charger composed of a charging wire made of a tungsten wire or the like and a shield plate (not shown) made of a metal plate, and is charged when a high negative voltage is applied to the charging wire. The line causes a corona discharge and forcibly recharges the toner synthesized on the intermediate transfer body 69. The pre-transfer charger 75 is activated only for the image area on the intermediate transfer body 69 immediately before the transfer to the recording paper 79, and is stopped in other periods. The pre-transfer charging improves the mechanical margin and the environmental characteristics during paper transfer.

The density sensor 76 is an application of a reflection type sensor, and detects the toner density on the intermediate transfer body 69.

The paper transfer roller 77 is composed of a metal central shaft and foamed silicon or conductive urethane rubber. When the toner image synthesized on the intermediate transfer member 69 is transferred onto a recording sheet, the toner image rotates in contact with the intermediate transfer member 69. When the paper transfer roller 77 is contaminated with toner or the like, an image is deteriorated. Therefore, a cleaning mechanism (not shown) is arranged in the vicinity.

The intermediate transfer member cleaning device 78 is a device for removing the residual toner on the intermediate transfer member 69 after the sheet is transferred, and while the toner image is being synthesized on the intermediate transfer member 69, the intermediate transfer member 69 is removed from the intermediate transfer member 69. It is separated and comes into contact only when it is used for cleaning.

Reference numeral 79 denotes a recording sheet, which is a final transfer medium for the toner image formed on the intermediate transfer member 69. Reference numeral 80 denotes a recording paper cassette in which recording paper is stored. The paper feed roller 81 is a half-moon shaped roller, and sends out the recording paper 79 from the recording paper cassette 80 to the paper transport path 82 one by one. A slip roller 83 is arranged in the middle of the paper transport path 82, and the recording paper 79 picked up by the paper feed roller 81 is transported by the slip roller 83 to the registration roller 84 a. When the leading end of the recording paper 79 reaches the registration rollers 84a, the registration rollers 84a
Is not rotating, and the recording paper 79 is slipping at the position of the slip roller 83 without proceeding. In this way, the registration roller 84a and the driven roller 84b temporarily stop the recording paper 79 in order to match the positions of the recording paper 79 and the composite image on the intermediate transfer body 69. At the time of operation, they rotate together and convey the recording paper 79 in the direction of the paper transfer roller 77.

The fixing device 85 includes a heat roller 86, a pressure roller 87, a temperature sensor 88 and the like. The heat roller 86 has a heater, an aluminum core, and a thickness of 0.5.
mm, and a heat source such as a halogen light source is disposed inside. The pressure roller 87 is made of an iron shaft and a silicon rubber having a thickness of about 3 mm, and applies pressure by sandwiching the recording paper 79 with the heat roller 86. Heat roller 86 and pressure roller 87
, The surface of the toner image is heated with heat and pressure to soften and melt the toner. By this action, the recording paper 79
The upper toner image is fixed on the recording paper 79 to form a color image. The temperature sensor 88 is a temperature sensor such as a thermistor, and detects the surface temperature of the heat roller 86. The output from the temperature sensor 88 is detected at an appropriate sampling period, and based on the detection result, the lighting time of the heater per unit time is controlled, and the specified temperature is always maintained.

The operation of the image forming apparatus 2 configured as described above when forming a color image will be described below. For simplicity, it is assumed that the image is formed in order of four colors of black, cyan, magenta, and yellow.

When an instruction to start printing is received from an external device (not shown, the external device corresponds to a copying controller which will be described in detail later), the photosensitive member 51 moves in the driving direction d2 and the intermediate transfer member 69. Are driven in the driving direction d3 by the same driving source (not shown). The speed reduction ratio is set so that the peripheral speed of these image carriers becomes the same constant speed by a speed reduction means (not shown).

When the photosensitive member 51 and the intermediate transfer member 69 reach the constant speed rotation, a high voltage of about -4000 V to -5000 V is applied to the charging line in the charger 59 connected to the high voltage power supply to cause corona discharge. Then, the surface of the photoconductor 51 is uniformly charged to about -700 V. Next, when the exposed surface of the charged photoconductor 51 is irradiated with an exposure light beam 66 modulated in accordance with, for example, black (K) print data, the irradiated portion on the photoconductor 51 loses its charge and the electrostatic latent image is discharged. An image is formed. The timing of starting the latent image formation at this time is determined by a signal from the intermediate transfer member position detecting sensor 74.

The black developing device 61K is driven in the driving direction d by rotation of the separation / contact cam 68K after a predetermined time has elapsed after a specific one of the plurality of intermediate transfer member position detecting marks 73 has been detected.
4 and comes into contact with the photoconductor 51. Immediately before the contact, a voltage of about -300 V is applied to the developing sleeve 67K, and after a lapse of a predetermined time after the contact, the rotation of the developing sleeve 67K is started.
When the rotation starts, toner is supplied from the black developing device 61K to the developing sleeve 67K. Since the charge of the toner is controlled to be negative, the toner adheres only to a portion (electrostatic latent image portion) of the photoreceptor 51 where the exposure light is irradiated and the charge disappears, so-called reversal development is performed. The black developing device 61K that has completed the development moves from the contact position with the photoconductor 51 to the separation position by rotating the separation cam 68K by 180 degrees.

The toner image formed on the photoconductor 51 by the black developing device 61K is transferred onto the intermediate transfer member 69 by the photoconductor 51.
The transfer is performed by applying a high voltage of about +800 V to the intermediate transfer roller 63 arranged in contact with the roller. Photoconductor 51
The residual toner not transferred to the intermediate transfer member 69 from
It is removed by the photoconductor cleaning device 64 and discharged to the outside. Further, the photosensitive member 5 from which the residual toner has been scraped off
The charge on 1 is removed by the static eliminator 65.

When the sensor 74 for detecting the position of the intermediate transfer member again detects the mark 73 for detecting the position of the intermediate transfer member used for generating the timing when forming the black image, the cyan (C) image is formed next. . When a predetermined period elapses after the detection of the mark 73 for detecting the position of the intermediate transfer member, the separation cam 68C
Rotates, and this time, pushes the cyan developing device 61C in the direction d4 to abut on the photoconductor 51 to start the development of cyan (C). The subsequent process is exactly the same as in the case of black.

Further, when the mark 73 for detecting the position of the intermediate transfer member for the third time is detected, magenta is formed for the fourth detection, and the images of the respective colors are sequentially superimposed on the intermediate transfer member 69, and the final image is formed. As a result, a combined image of four colors is formed on the intermediate transfer member.

On the other hand, during the formation of the image of the fourth color (yellow), the paper feed roller 81 is rotated to feed the recording paper 79 from the recording paper cassette 80 to the paper transport path 82. Recording paper 79
Stops temporarily between the registration roller 84a and the driven roller 84b. Next, at the timing when the leading end position of the composite image formed on the intermediate transfer body 69 becomes the specified position of the recording paper 79,
The rotation of the registration roller 84a is started. After the rotation of the registration roller 84a, the paper transfer roller 77 that has been separated until now is brought into contact with the intermediate transfer body 69, and when a high voltage of about +1000 V is applied to the paper transfer roller 77, the paper transfer roller 77 is formed on the intermediate transfer body 69. The composite image is collectively transferred to the recording paper 79 by Coulomb force and pressure. The recording paper 79 onto which the toner image has been transferred is conveyed to a fixing device 85, where the recording paper 79 is fixed by the heat of the heat roller 86 and the sandwiching pressure of the pressure roller 87, and is output as a color image. Meanwhile, recording paper 79
The residual toner on the intermediate transfer member 69 that has not been completely transferred to the intermediate transfer member 69 is removed by the intermediate transfer member cleaning device 78. The intermediate transfer member cleaning device 78 is at a position away from the intermediate transfer member 69 during the formation of the composite image, and is in a contact state after the composite image is transferred to the recording paper 79 by the paper transfer roller 77. And the residual toner is removed.
With the above operation, recording of one image is completed, and a color recorded image is obtained.

Next, the configuration of a copying controller built in the image forming apparatus 2 will be described.

FIG. 6 is a block diagram showing a copying controller constituting the image forming apparatus 2 of the image copying system according to the first embodiment of the present invention. The copying controller shown in FIG. It processes image data and controls the image forming apparatus 2. In the description with reference to FIG. 4 described above, the image reading apparatus 1 is described as being directly connected to the image forming apparatus 2. However, the image reading apparatus 1 is actually connected to a copying controller. In this embodiment, the copy controller is built in the image forming apparatus 2. That is, as shown in FIG. 6, the image forming apparatus 2 includes a copy controller and an image forming unit 2A.

In FIG. 6, reference numeral 90 denotes a copying controller built in the image forming apparatus 2, 91 denotes a scanner interface (scanner I / F) for outputting a command to the image reading apparatus 1 and receiving image data, and 92 denotes a scanner interface. An image processing unit 93 that processes image data input from the image reading device 1 to generate data in a format in which an image can be formed, 93 processes the image data input from the image reading device 1 to prohibit copying. A characteristic amount extraction unit (specific image detection unit) for extracting a characteristic amount indicating a characteristic of the specified image, 9
Reference numeral 4 denotes a page memory (storage unit) for storing at least one image data processed by the image processing unit 92. The page memory 94 stores binarized image data for the four primary colors C (cyan), M (magenta), Y (yellow), and K (black) for printing. Reference numeral 95 denotes an engine interface for outputting image data stored in the page memory 94 to the image forming apparatus 2, and reference numeral 96 denotes a system bus. Each module (each block) in the copying controller 90 transmits and receives data using this system bus. Reference numeral 97 denotes a work memory used as a work area when performing image processing, detection of a specific document, and the like. 98 denotes a module that controls each module via a system bus 96 and performs image processing based on image feature amounts extracted by a feature amount extraction unit 93. C for detecting whether or not a specific image is included in data in a plurality of stages
A PU (control unit) 99 is a ROM. All the CPUs 98 operate according to the programs stored in the ROM 99.

Next, referring to FIG.
The process of processing the image data input from will be described.

The CPU 98 controls the scanner interface 9
A predetermined control command is output to the image reading apparatus 1 through the control unit 1 (details of the control command will be described later).
The image reading device 1 reads a document according to the transferred control command and outputs color image data. The output image data is received by the scanner interface 91 and sent to the image processing unit 92 and the feature amount extracting unit 93. The image processing unit 92 performs color processing and the like on the color image data to convert the data into a data format that can be formed by the image forming unit 2A. The image data processed by the image processing unit 92 is stored in the page memory 94.

On the other hand, the color image data received by the scanner interface 91 is also output to the feature amount extracting section 93. The feature extraction unit 93 extracts a feature for detecting whether or not the color image data includes a specific image whose copying is prohibited. The CPU 98 determines in a plurality of stages whether or not a specific image exists in the input color image data based on the extracted feature amount. In the present embodiment, the temporary determination, the secondary determination, and the final determination Is determined in three stages.

The color image data is stored in the page memory 9.
When one image is stored in the CPU 4, the CPU 98 controls the engine interface 95 to instruct the image forming unit 2A to start the operation, but after instructing the operation to start, the specific image may be included in the temporary determination. If it is determined that
The operation start instruction already output to the image forming unit 2A is canceled (for example, the instruction signal instructing the operation start is output by outputting a hold signal). As a result, the operation of the image forming apparatus 2 is temporarily stopped. Since this temporary determination is performed at a very high speed as described later,
In the image forming process of the image forming unit 2A described above, no image is actually formed.

If it is determined in the tentative determination that the read image does not include the specific image, the printing operation is not canceled, and the color image data in the page memory 94 is output via the engine interface 95. Immediately, printing is performed in the image forming unit 2A. Therefore, when the specific image is not detected in the tentative determination, an image can be formed at high speed.

On the other hand, when it is determined in the tentative judgment that the read image includes the specific image, a more detailed check is performed and a final judgment result is obtained. If a specific image is detected in the final determination, the CPU 98 directly rewrites the image data in the page memory 94 to perform processing for preventing forgery. Since this processing is performed on the image data stored in the page memory 94, for example, a predetermined character string or pattern can be overwritten at high speed. Further, as will be described in detail later, reduction by thinning or the like can be easily performed.

When the specific image is not detected in the final judgment, the CPU 98 releases the hold instructed to the engine interface 95. As a result, image data that has not been subjected to forgery prevention processing is printed by the image forming unit 2A.

Next, the interface between the copying controller 90 and the image reading apparatus 1 and the transfer of control commands and image data will be described.

First, the interface between the copying controller and the image reading apparatus, particularly the transmission and reception of data by the SCSI command, will be described in detail with reference to FIGS. 6 and 19. FIG. 19 is a sequence diagram showing a processing procedure for a command exchanged between the copying controller 90 and the image reading apparatus 1 and data to be transferred. A solid arrow in the drawing indicates that a command has occurred in that direction, and a broken arrow indicates that data is sent in that direction.

In the following description, SCSI will be described as an example for the sake of simplicity. Of course, even if the interface is another interface, if the image forming apparatus 2 and the image reading apparatus 1 can perform bidirectional communication, the same procedure is used. Can be adopted. Further, for ease of explanation, it is described that the copying controller 90 issues a command or the like to the image reading apparatus 1, but more correctly, it is written in the ROM 99 mounted on the copying controller 90. The CPU 98 controls the image reading device 1 according to the program.

When reading image data, first, the copying controller 90 sends the image reading device 1 a T
Issue an EST UNIT READY command. Upon receiving this command, the image reading device 1
The status of the image reading device such as SY or READY is returned to the copying controller 90 (S100). The copy controller 90 waits until the returned state becomes READY.
Issue a TEST UNITREADY command periodically.

When the image reading device 1 returns READY in response to the TEST UNIT READY command, the copying controller 90 determines that the image reading device 1 is in a readable state, and issues a MODE SENSE command. Upon receiving this command, the image reading apparatus 1 operates the operation panel (not shown) arranged on the image reading apparatus 1 side, that is, whether or not an instruction to start copying has been issued (hereinafter, “copy start key”). information"
, Or information about a user operation such as what reading mode is selected is output to the copying controller 90 (S101). The copy controller 90 periodically outputs a MODE SENSE command until the start of copying is instructed by the copy start key information, and continues to obtain information on the operation panel from the image reading apparatus 1.

When it is determined that the copy start is instructed by the copy start key information, the copy controller 90
Issues a MODE SELECT command. With this command, the copying controller 90 causes the image reading device 1
Is passed to the control parameter (S102). The control parameters include, for example, information as to whether or not to use the automatic document feeder (ADF) in the image reading device 1;
Information such as the unit system when specifying the reading range is included.

Next, the copying controller 90 issues a SETWINDOW command to the image reading device 1. Following this command, the copying controller 90 passes the image reading conditions to the image reading device 1 (S103). The image reading conditions include information such as an image reading start position (information on a reading origin), a reading range (information on an image size to be read), and an image reading resolution. Based on the resolution information passed by this command, the image reading device 1 sets the resolution conversion unit 27 (see FIG. 4). In the present embodiment, as the image reading conditions,
The reading resolution is set to 600 dpi, and the reading range is set to, for example, the entire LETTER size from the top of the readable position.

Next, the copying controller 90 issues a SCAN command to the image reading device 1 (S
104). Thereby, the image reading apparatus 1 starts the rotation of the driving source (the driving source 8 in FIG. 2) and prepares for the image reading.

Next, the copying controller 90 sends a GET PIXEL NUMBE to the image reading device 1.
Issue an R command. The image reading apparatus 1 that has received this command calculates the actual number of pixels per line, the amount of data, and the like from the image size and the reading resolution received in step 103, and returns the result to the copying controller 90 (S105). ). SET WI in this way
For the reading conditions specified by the NDOW command,
By returning the actual setting value on the reading device 1 side, for example, when the specified value of the reading range requested by the copying controller 90 is higher than the accuracy handled by the image reading device 1, the matching between the devices can be achieved. . Normally, the copying controller 90 follows the value returned from the image reading device 1.

Next, the copying controller 90 sends a GET DATA BUFFER to the image reading device 1.
Issue a STATUS command. The image reading device 1 that has received this command returns the amount of image data that has not been transferred to the copying controller 90 (S10).
6).

Next, the copying controller 90 sets the REA
A D command is issued, and a predetermined amount of image data is received from the image reading device 1 (S107).

The processing from step 106 to step 107 is repeated until it is determined in step 106 that there is no remaining data to be transferred.

Next, an interface between the copying controller 90 and the image forming section 2A will be described.

FIG. 20 is an interface diagram showing details of the engine interface 95 for connecting the copy controller 90 and the image forming section 2A. As shown in FIG. 20, the engine interface 95 and the image forming unit 2A transmit and receive signals through a plurality of lines. In FIG.
140 is a clock signal line, 141 is a line synchronization signal line indicating the start of one line, and a clock signal CLK.
And the line synchronization signal BDS are output from the image forming unit 2A in the direction of the engine interface. Reference numeral 142 denotes an image data line, and the copying controller 90 (to be precise, the CPU 98) outputs the image data DATA in synchronization with the clock signal CLK and the line synchronization signal BDS. Reference numeral 143 denotes a print control signal line. When the print control signal PRINT is turned on, the image forming unit 2A starts image formation. 144C, M, Y, and K are print color designation signal lines, and print color designation signals CENB, MENB, Y
ENB, KENB (commonly described as "ENB")
, One bit for each of the printing color materials C, M, Y, and K specified by the total of four bits. A serial communication line 145 performs bidirectional communication between the engine interface 95 and the image forming unit 2A.

The operation of the above-described engine interface 95 will be described with reference to FIG.

When the image data DATA for forming an image is prepared, the engine interface 95 transfers the conditions for forming an image to the image forming unit 2A through the serial communication line 145 under the control of the CPU 98. Conditions for forming an image include, for example, the size of an image to be transferred, that is, the number of pixels in the main scanning direction and the number of lines in the sub-scanning direction, the paper size, the use of a manual feed tray for paper feeding, and the paper discharging direction. (Although not shown, the image forming section 2A of the present embodiment can discharge the sheet, that is, switch between face-up and face-down).

Next, the CPU 98 sets the print color designation signal ENB via the engine interface 95.
Thus, for example, when a full-color image is formed using four color materials of CMYK, all the lines 144C, 1C
The print color control signals ENB of 44M, 144Y and 144K are turned on. When a monochrome image is formed, the printing color control signal KENB of the printing color control signal line 144K is used.
By turning ON only, printing of a single black color can be performed.

When the setting of the print color designation signal ENB is completed, the CPU 98 controls the print control signal PRINT to be ON for a predetermined period. When the image forming unit 2A confirms that the print control signal PRINT is turned on, the image forming unit 2A immediately starts image formation. However, the image forming unit 2A has a driving source (not shown) for driving the exposure optical system 60 and the photoconductor 51. ), Components that can be operated only after reaching a certain number of rotations are included, and cannot enter the substantial image forming process until they reach a predetermined number of rotations. Next, the image forming unit 2A re-prints the print control signal PRINT when all of these mechanisms are ready to form an image.
Check the status of. At this point, the print control signal PRINT
If the state is kept ON, the image forming section 2A starts the image forming process and forms an image based on the designated condition. However, if the state of the printing control signal PRINT is OFF, the drive source or the like that has already started up is immediately stopped, and the operation returns to the standby state.

The above is the operation when the image forming section 2A is on standby. Even when a plurality of pages are continuously printed, the state of the print control signal PRINT is divided into a plurality of times. Confirmation step. This is because the circumference of the photoreceptor 51 and the intermediate transfer body 69 of the image forming unit 2A is designed to be longer than the maximum recording size that can form an image, so that the image forming unit 2A continuously forms images. ,
Until the next page is started after the image formation of a specific page is completed and before the output necessary for generating the timing is detected using the mark 73 for detecting the position of the intermediate transfer member formed on the intermediate transfer member 69. This is possible because there is a time difference of at least several 100 ms.

When the image forming section 2A is ready to form an image, the clock signal CLK and the line synchronizing signal BD
S is output to the engine interface 95. These signals are used by the hardware of the copying controller 90 to transfer the image data DATA to the image forming unit 2A.

Next, the image processing section 92 and the feature quantity extracting section 93 in the copying controller 90 will be described with reference to FIG. FIG. 7 is a block diagram showing details of the image processing unit 92 and the feature amount extracting unit 93 of the copying controller 90.

First, the processing contents of the image processing section 92 will be described.

In FIG. 7, reference numeral 91 denotes a scanner interface similar to that of FIG. 6, 92 denotes an image processing unit similar to that of FIG.
3 is a feature amount extraction unit similar to FIG. 6, 94 is a page memory similar to FIG. 6, 95 is an engine interface similar to FIG. 6, 98 is a CPU (control unit) similar to FIG. 6, and 100 is a density conversion unit. , 101 is a UCR / black generation unit, 102 is a color correction unit, 103 is a γ correction unit, 104 is a gradation processing unit, 105 is a specific resolution conversion unit, 106 is a feature amount calculation unit, and 107 is a buffer.

The operation and the like of the image processing section 92 thus configured will be described.

The density conversion section 100 performs logarithmic conversion of the luminance data R, G, and B transferred from the scanner interface 91 and converts them into density data Dr, Dg, and Gb. A lookup table is used for this conversion. UCR
/ Black generation unit 101 obtains the minimum value of the density data Dr, Dg, Gb, and subtracts a value obtained by multiplying the minimum value by a predetermined ratio from the density data of each color.
(Removal) processing. Further, the density data D
The minimum value of r, Dg, Gb is multiplied by a predetermined ratio, and black = K (Bl
ack) Generate data. A so-called skeleton black can be generated by using a look-up table for the conversion to black ink. The color correction unit 102 removes unnecessary absorption components of the recording color material of the image forming apparatus 2 from the color components other than K in the image data on which the UCR / black generation has been completed, and corrects the color components into vivid colors without turbidity. The printer print colors C (Cyan), M (Magenta), Y (Ye
lllow). In the conventional color correction processing, a 3 × 3 matrix operation or the like has been used. However, such linear operation has a limit in correction accuracy, so recently, a three-dimensional space is divided into a grid and obtained in advance. By performing a weighting operation based on each grid point information (although each division space is a linear operation), a quasi-nonlinear correction can be realized as a whole.

The gamma correction unit 103 corrects a non-linear component of the gradation characteristic caused by the image forming process of the image forming apparatus 2 using a look-up table. Up to the γ correction unit 103, the color image data is multi-valued data, for example, each color data is 8 bits / pixel. In general, the γ correction unit 103 converts image data into non-linear data, and thus involves a decrease in accuracy. Therefore, the color data of each color is set to 10 bits / pixel, and this can be corrected using a lookup table of input 10 bits.

The gradation processing unit 104 performs a binarization process on the image data based on, for example, the systematic dither method or the error diffusion method. The binarized image data of each color is stored in the page memory 94. When storing, page memory 9
4, the image data can be output to the image forming unit 2A at high speed via the engine interface 95 by, for example, burst transfer.

Next, the operation of the feature amount extraction unit 93 will be described.

The feature extracting unit 93 extracts a predetermined feature from the image data in order to detect whether or not a specific image exists in the read image data. The specific resolution conversion unit 105 converts the read image data into a specific
The resolution is converted to a resolution of 5 dpi (dot per inch). The characteristic amount calculation unit 106 obtains a characteristic amount for determining whether or not a specific image exists based on the image data converted to a specific resolution by the specific resolution conversion unit 105.
The buffer 107 stores the feature of the image output from the feature calculator 106. The feature data stored in the buffer 107 is accessible from the CPU 98. The CPU 98 specifies the image data input in three stages of the tentative determination, the secondary determination, and the final determination based on the input feature data. It is determined whether an image is included. Also CP
The U98 controls the transfer of the image data already stored in the page memory 94 by operating the engine interface 95 based on the above determination result.

Next, a description will be given of a feature amount extraction process in the feature amount extraction unit 93.

FIG. 8 is a block diagram showing the configuration of the feature quantity extracting section 93 in more detail.

In FIG. 8, reference numeral 91 denotes a scanner interface similar to that of FIG. 6, reference numeral 93 denotes a feature amount extraction unit similar to that of FIG.
Reference numeral 95 denotes an engine interface similar to that of FIG. 6, 97 denotes a working memory similar to that of FIG. 6, 98 denotes a CPU (control unit) similar to that of FIG. 6, 99 denotes a ROM similar to that of FIG. 7, a buffer similar to that shown in FIG. 7, 110 is a low-resolution image memory, 111 is a feature color counter, 112 is a template selection unit, 113 is a template storage memory, 115 is a main / sub pixel counter, 116
Is an interrupt signal line.

The operation and the like of the feature amount extracting unit 93 thus configured will be described in more detail.

In FIG. 8, specific resolution conversion section 105
Converts input image data into a specific image, for example, 75 dp.
i to a relatively low resolution. The low-resolution image memory 110 stores the image data converted to a specific resolution by the specific resolution conversion unit 105. Feature color counter 111
Generates the feature vector data by counting the number of image data in a predetermined range of a plurality of colors set in advance by the CPU 98. The template selection unit 112 compares the feature vector data generated by the feature color counter 111 with a plurality of templates prepared in advance, and selects and outputs the template with the closest Euclidean distance. The template storage memory 113 stores a plurality of templates used by the template selection unit 112 for comparison with the feature vector (the plurality of templates are also set in advance by the CPU 98). The buffer 107 temporarily stores the count value of the characteristic color counted by the characteristic color counter 111, the number of the template selected by the template selection unit 112, and the Euclidean distance between the characteristic vector data and the template. The main / sub-pixel counter 115 counts the number of input image data in the main scanning direction and the sub-scanning direction, and outputs an interrupt signal INTR to the CPU 98 every time the count reaches a predetermined count. When the CPU 98 receives the interrupt signal INTR, the CPU 98 reads the contents of the buffer 107 and acquires the feature amount.

By the way, at the time of inputting color image data from the image reading device, the CPU 98 has already obtained information of the reading resolution and the reading range (not shown, but the CPU 98 transmits the information through the scanner interface via the scanner interface). The output of the control command to the image reading apparatus 1 has been described above, and the CPU 98 controls the image reading apparatus 1 from the outside, such as a reading resolution specified by an operation panel or the like (not shown) or a specification content regarding a reading range. These control commands will be described later in detail). Based on the information of the reading resolution, the setting of the specific resolution conversion unit 105 is changed according to the reading resolution to be scanned by the image reading apparatus 1, and does not depend on the reading resolution of the image reading apparatus 1.
Always convert to image data of a specific resolution. As a method of converting an arbitrary resolution to a specific resolution in this manner, a known method such as linear interpolation can be used. By converting the input color image data to a specific resolution in this way, a specific image can be recognized with one recognition algorithm. The specific resolution described above is set to 75 dpi in the present embodiment. By detecting the specific image using the image data converted to the low resolution in this way, the resolution range in which the specific image can be recognized can be greatly expanded.

Next, the specific resolution converter 105 will be described in detail.

The input of the specific resolution converter 105 is color image data of an arbitrary resolution. In the case of the image reading apparatus 1 according to the present embodiment, the resolution of the optical system such as the image sensor 20 and the lens is 600 dpi.
Images can be scanned at resolutions between pi and 2400 dpi. The CPU 98 is a side that specifies the reading resolution of the image reading device 1 and since the resolution of the input color image data is known in advance, the CPU 98 sets the magnification in the specific resolution conversion unit 105 according to the reading resolution. For this type of resolution conversion, a known method such as linear interpolation or cubic convolution is used. In the present embodiment, a linear interpolation method with a simple hardware configuration is used. The reading resolution is 600dp
If it is larger than i, simple pixel thinning is first performed to reduce the number of pixels to be processed, thereby enabling high-speed processing.

Through the above processing, image data having a specific resolution of 75 dpi is obtained in both the main scanning and sub-scanning directions. The resolution of 75 dpi is higher than the optical resolution of 600 dpi of the image reading apparatus 1 of the present embodiment. It is a sufficiently small value. By recognizing the specific image using the image data converted to a resolution sufficiently smaller than the optical resolution of the image reading device 1, it is possible to recognize the specific image substantially without depending on the reading resolution. it can. Since this can substantially eliminate the limitation of the resolution when recognizing the specific image, for example, it is possible to copy the specific image for which copying is prohibited by performing a reduced copy once and then performing an enlarged copy again. Malicious actions can also be prevented.

In the present embodiment, the resolution used for detecting a specific image is specified as 75 dpi, but the specific resolution is not limited to 75 dpi. For example, 300d
Pi or 150 dpi may be processed at a specific resolution. Although the specific resolution can be flexibly determined according to the reading resolution range of the image reading device 1, according to an experiment conducted by the present inventors, in the existing, particularly flat-bed type image reading device, 30
If the predetermined resolution is set to 0 dpi or less and 75 dpi or more, the specific image can be recognized without any problem in accuracy.

Next, the specific image recognition algorithm in the feature amount extraction unit 93 will be described with reference to FIG.

The RGB image data converted to a specific resolution by the specific resolution conversion unit 105 is temporarily stored in the low resolution image memory 110. Low resolution image memory 11
The RGB image data stored in 0 is cut out in block units of a predetermined size and sent to the characteristic color counter 111 as RGB point sequential signals. The size of the block is set to, for example, 50 × 50 pixels (2500 pixels). The characteristic color counter 111 counts the number of pixels falling within a range of RGB values determined in advance as characteristic colors for the input RGB image data. This count range is set in advance in the characteristic color counter 111 by the CPU 98 during operation. In the present embodiment, three different colors included in a specific image are defined as characteristic colors, and the number of pixels determined to be characteristic colors is counted for each block. When the counting of the characteristic colors of one block is completed, the result is transferred to the template selecting unit 112 and written into the buffer 107.

The output from the characteristic color counter 111 is obtained by counting the number of a plurality of characteristic colors existing in a 50 × 50 pixel block. Since the number of characteristic colors is 3, this can be regarded as outputting a three-dimensional characteristic vector. That is, the characteristic color counter 1
Reference numeral 11 indicates that a feature vector is being generated. The template selection unit 112 compares the feature vector generated by the feature color counter 111 with a plurality of templates stored in the template storage memory 113 based on the three-dimensional Euclidean distance, selects the closest template, and The number and the three-dimensional Euclidean distance are stored in the buffer 107. The nearest neighbor template number and the three-dimensional Euclidean distance serve as indices indicating the similarity between the input image data and the specific image.

The total number of pixels processed by the characteristic color counter 111 is counted and managed by the main / sub-pixel counter 115. When the counted result of the number of pixels processed reaches a predetermined amount, the main / sub-pixel counter 115 counts the number of pixels. The sub-pixel counter 115 is a CPU 98
Generates an interrupt signal INTR. Upon receiving the interrupt signal INTR, the CPU 98 reads the buffer 107, and stores the characteristic color count result stored therein.
The nearest neighbor template number and the three-dimensional Euclidean distance are acquired. The CPU 98 selects the similarity based on the nearest template number read from the buffer 107 and the similarity based on the three-dimensional Euclidean distance for a plurality of blocks according to a certain rule, calculates the sum of them, and outputs the result of the tentative determination according to the sum I do. This determination algorithm will be described later in detail.

Next, the characteristic color counter 111 will be described in detail. FIG. 9 is a block diagram showing the characteristic color counter 111.

In FIG. 9, 120_C0, 120_C
Reference numerals 1 and 120_C2 denote characteristic color detectors for detecting independent characteristic colors, respectively. In the embodiment, three characteristic colors are detected, and therefore, three characteristic color detecting units are provided. Since there is no difference in configuration between the characteristic color detectors except that they detect different colors, only one color is shown in detail. A comparator 121 compares the input RGB image data with a predetermined value and detects whether the image data falls within a predetermined range. An AND gate 122 performs an AND process on the output of the comparator 121 and outputs the result. A counter 123 counts the number of times the output of the AND gate becomes 1. A count buffer 124 accumulates the count result of the counter 123.

The characteristic color counter 111 having the above configuration
Will be described in detail below.

The characteristic color counter 111 is a part for detecting three specific colors included in a specific image and detecting the respective numbers. Here, for the sake of simplicity, the characteristic color counter 111 detects one characteristic color. The operation of the unit 120_C0 will be described in detail.

First, the input RGB image data is compared by the comparator 71 with the designated color signal. The designated color signal is set in the register of the comparator 121 by the CPU 98. The designated color signal designates a color included in the specific image, is obtained in advance by performing statistical processing on the color included in the target specific image, and is generally used for the background color or pattern of the specific image. A color distributed in the range, a vermilion of an imprint, or the like is used. In addition, when specifying a color, the upper and lower limits of RGB are specified, for example, as r_ref1 (lower limit for the R signal) and r_ref2 (upper limit for the R signal) in order to give the specified color a width. , Pixels in these ranges are treated as specific color pixels. The outputs of the comparators 121 are collected by an AND gate 122. When the input RGB image data is in a specific color range, the outputs of the comparators 121 are all "1", so that the output of the AND gate 122 is "1". Becomes
The number of pixels of the specific color pixel detected in this way is determined by the counter 1
Count by 23.

The counting is performed in block units. Here, the block is a block in which the read image is divided in units of a plurality of pixels in the main scanning direction and the sub-scanning direction.
A 50 × 50 pixel rectangle is defined as one block, with a unit of 50 pixels for a pixel having a specific resolution of dpi. Therefore, the counter 123 saves the count result in the count buffer 124 every time 50 pixels are input and is reset.
The count buffer 124 exists for the number of blocks in the main scanning direction, and records data for one block in the sub-scanning direction. At the time of recording from the counter 123 to the count buffer 124, the result of addition to the data already written on the count buffer 124 is always written.
That is, by performing the read-modify-write operation, the number of characteristic color pixels in one block in the sub-scanning direction is accumulated. When data input for one block is completed in the sub-scanning direction, the contents of the count buffer 124, that is, the result of counting the characteristic colors obtained for each block, are stored in the buffer 107 and passed to the template selecting unit 112. .

The above operation is performed by the characteristic color detector 120_C1,
It is also performed in parallel in the characteristic color detection unit 120_C2,
Three characteristic colors are counted with respect to a predetermined designated color signal, and each count result is a three-dimensional vector,
That is, it is transferred to the template selection unit 112 while being stored in the buffer 107 as a feature vector.

FIG. 10 is a data structure diagram showing the structure of data stored in the buffer 107. In the figure, a thick solid line indicates the break of each block, and C0 (n), C1
(N) and C2 (n) indicate the result of the characteristic color pixel count counted in the n-th block, respectively, and indicate that one block characteristic data is composed of three specific color pixel numbers. .

FIG. 11 is a flowchart showing the operation of the template selection unit. Hereinafter, the operation of the template selection unit 112 will be described in detail with reference to FIGS.

When the feature vector composed of the count values of the three feature colors is passed from the feature color counter 111 to the template selection unit 112 for each block, the feature vector is compared with the template. First, a feature vector for each block is obtained (S1). The acquired data is Cn = (C0
(N), C1 (n), C2 (n)) (where n is the block number). It is determined whether or not the magnitude | Cn | of Cn is equal to or greater than a predetermined value (S2). If the number is equal to or more than a certain value, a template closest to Cn is searched from the templates stored in the template storage memory 113. The template of the template storage memory 113 is T
m = (TC0 (m), TC1 (m), TC2 (m))
(Where m is a reference data number and m = 1 to M), and the distance Dnm = | Cn−Tm |
The Dnm at which (the Euclidean distance of the three-dimensional vector) becomes minimum is detected, and the template number m and the distance data Dmin are stored in the buffer 107 (S3). If | Cn | does not exceed a certain value in step 2, the template search in step 3 is not performed, and the template number (for example, M
+1) and the value Dmax equal to or larger than the maximum value of Dnm can be stored in the buffer 107 (S4).

Here, the template stored in the template storage memory 113 will be described in detail.

[0138] The template storage memory 113 is a RAM, and the data of the template is set by the CPU 98. The template data is obtained in advance from the specific image to be processed, and these are stored in, for example, the ROM 99 or the like.

FIGS. 12A to 12D are relationship diagrams showing the relationship between the template and the specific image. As shown in FIG. 12, the template is based on the specific image to be positioned at the horizontal position as a reference (FIG. 12A), and when the specific image to be rotated from the horizontal position by a minute angle unit ( 12 (b)) (FIG. 12 (c)). Also, when the positional relationship between the block and the specific image is shifted by several pixels in the horizontal and vertical directions (FIG. 12 (d)), ,
A template obtained by calculating the number of pixels worth each characteristic color is used as a template. However, since the number of templates obtained as described above is enormous, a representative one is extracted using a clustering method such as vector quantization, and RO is extracted.
It is stored in M99.

Next, a process from recognition of a specific image to provisional determination will be described.

First, the specific image recognition process will be described with reference to FIG.

The output of the template selection unit 112 is temporarily stored in the buffer 107. When these processes have been completed for a predetermined number of blocks, the main / sub-pixel counter 115 generates an interrupt signal INTR and requests the CPU 98 to acquire the contents of the buffer 107.

The CPU 98 reads the contents of the buffer 107 and stores it in the working memory 97. FIG. 13 is a data configuration diagram showing a data configuration in the working memory 97. In the figure, TN (n) is a template number closest to the feature vector obtained for each block. D (n) is obtained for each block,
Distance Dmin from template closest to feature vector
Or it is Dmax.

FIGS. 14A to 14C are image diagrams showing TN (n) and D (n) images given to each block of the specific image. FIG. 14A shows an image including a specific image, and FIG. 14B shows the value of TN (n) for each block. Here, the template number is up to 254, which is defined as a template. Unassigned numbers are 254 + 1 = 255. FIG.
(C) shows the value of D (n) for each block, and the "00" part in the figure shows Dmax or a value close to it, and it is said that the image is not completely similar in color to the specific image. Means that. “02” in the figure is Dmi
n, which means that the value of the distance between the feature vector and the template is 0 or a value close to it, that is, an image whose color is very similar to the specific image. The “01” part in the figure indicates an intermediate value, that is, an ambiguous image. CPU
Reference numeral 98 denotes TN (n) developed on the working memory 97 and D
Based on the distribution state of (n) and a frame mask described later,
A tentative determination is made on the presence or absence of a specific image.

First, the frame determination processing performed using D (n) will be described. In the frame determination process, a group of a plurality of adjacent blocks is regarded as one frame, and the frame is processed while shifting its center position from the upper left of the input image horizontally and vertically in units of one block.

Next, the frame mask shown in FIG.
This will be described with reference to (a) to (d). FIG.
(D) is a frame mask structure diagram showing the structure of the frame mask. The frame mask is used to mask blocks constituting a frame, and a plurality of masks having different mask angles are prepared as shown in FIG. In FIG. 15, a hatched square indicates a mask block, and a white square indicates a non-mask block. The former is represented by a binary code of “0” and the latter is represented by a binary code of “1”, and is stored in the ROM 99 (see FIG. 8).

FIG. 16 is a flow chart showing the processing contents for one frame in the frame processing.

First, the distance D (n) between the feature vector and the selected template is set for the block at the center of the frame.
Is read and compared with the threshold Th1 (S11), and the threshold Th
If it is greater than 1 (the distance is far), it is determined that there is no specific image for this frame, and the process moves to the next frame. If it is equal to or smaller than the threshold Th1 (when the distance is short), one of the frame masks is obtained from the ROM 99 (S1).
2). The acquired frame masks are sequentially examined for each block, the following processing is skipped for the mask block, and D (n) of the corresponding block is acquired from the working memory 97 for the non-mask block ( S1
3, S14). The acquired D (n) is sequentially added to Dsum (S15), and a counter value Bnum for counting the number of blocks subjected to the processing is incremented (S16). The processes from step 13 to step 16 are performed until the blocks constituting the frame are completed (S
17). Sum D of block number counter value Bnum and distance D
The average distance Dmean is obtained from the sum (S18), and is compared with the threshold Th2 (S19). Dmean ≦ T
In the case of h2, it is determined that there is a high possibility that the specific image is included in the image. If Dmean> Th2, it is determined that there is no specific image, and steps 12 to 19 are repeated with the frame mask changed (S20).

The above is the process of the tentative decision. The meaning of the tentative decision will be described below with reference to FIG. In FIG. 8, C
The PU 98 stores the feature vector extracted by the feature color counter 111, the template number calculated by the template selection unit 112, and the three-dimensional Euclidean distance between the feature vector and the selected template in the buffer 107.
Can be obtained in real time via. Since these extractions and calculations are performed by hardware, no burden is placed on the CPU. The above-described frame processing is C
PU98 does this, but saves time by performing it in parallel with the input of color image data. In the frame processing, since the processing is performed by sequentially switching the frame mask, the CPU 98 is required to have a certain processing performance.
With recent CPU performance, frame processing can be performed almost in real time.

However, if the CPU performance is low, a method of referring to the template number calculated by the template selection unit 112 and the three-dimensional Euclidean distance between the feature vector and the selected template may be considered. That is, for example, a pattern in which a template corresponding to a specific image appears is stored in advance, and only a template number having a small three-dimensional Euclidean distance is extracted,
The provisional determination may be made by comparing the appearance patterns.
By doing so, the processing can be performed in the order in which the templates appear, as compared with the area frame processing, so that higher-speed processing can be performed.

The result of the tentative judgment thus determined is output from the CPU 98 to the engine interface 95. The control for the engine interface 95 will be described later.

Next, the secondary determination will be described. When it is determined that there is a high possibility that the specific image is included in the image being processed in the above-described frame determination processing, a secondary determination is performed. Hereinafter, the secondary determination processing will be described with reference to FIGS.

FIGS. 17A and 17B are diagrams showing rotation angle correction in the secondary determination. For the secondary determination, TN (n) in which a template number closest to the feature vector of each image block is described is used. However, the image cut out by the frame determination processing may include a specific image that is not in the normal arrangement.

Step 19 of the above-described frame determination process
In, depending on the type of frame mask used at the time when it is determined that the specific image is likely to be included in the image,
At the stage of frame determination, it is possible to give an idea of the angle at which the specific image is arranged. TN based on this information
(N) is relocated to the normal position. FIG. 17 shows the situation. FIG. 17 (a) shows the state before rotation correction.
(B) shows the situation after rotation correction. In each figure,
The positions of ○, □ and △ correspond.

Next, the secondary judgment processing will be described with reference to FIG. FIG. 18 is a recognition process relationship diagram showing the relationship between the frame, the block, and the recognition process in the secondary determination, and assumes that the above-described rotation correction has been performed. ○ in the figure
The marks, □, and Δ correspond to those in FIG. FIG.
In FIG. 18B, the block after the normal placement is partly in a stepped shape, but in the secondary determination, as shown in FIG. 18, the processing is performed assuming that the specific document has been placed correctly.

In FIG. 18, reference numeral 125 denotes a set of blocks in which TN (n) has a value other than 255 (= template undefined) for a frame determined to have a high possibility that a specific image exists in the frame determination. is there. Reference numeral 126 denotes blocks included in the block set 125, and a template is described for each block as a histogram for ease of explanation. 127 is a secondary determination unit, which is configured by a neural network. 12
8 denotes an input layer of the neural network, 129 denotes an intermediate layer of the neural network, and 130 denotes an output layer of the neural network. Reference numeral 131 denotes a comparing unit that compares two outputs output from the output layer 130 and selects a larger one. Note that the secondary determination unit 127 may be configured by any of software and hardware.

By the way, the blocks converted into the normal arrangement positions by the rotation correction have template numbers TN respectively.
(N). Since the template number is actually the feature vector itself included in the specific image, these can be represented by a histogram as shown in a block 126 in FIG. The frequency of this histogram is input to the input layer 128 of the secondary determination unit 127. The input layer 128 has three histograms for one input unit.
It has three nodes to correspond to the dimensional information, and the frequency of the histogram is input to each node. The frequency is input to the nodes corresponding to all the blocks. In the neural network, an operation is performed in the intermediate layer 129 by a weighting operation that has been learned in advance, and the output layer 130 outputs a degree that looks like a specific image and a degree that does not look like a specific image. Finally, the comparing means 131 selects and outputs the one that has output a greater degree. Therefore, the output of the comparing means 131 is a binary output indicating whether or not the input image is a specific image.

The secondary determination is performed as described above.

Next, the final judgment will be described.

Now, it is determined whether or not a specific image exists in the image read by the image reading apparatus 1 through the above-described temporary determination and secondary determination. However, erroneous determination is always possible in this type of recognition. There is. In particular, in the case of a device that detects a specific image for which copying is prohibited, if a general image is recognized as a specific image, there is a problem that an image for which copying is not prohibited is not copied. Hereinafter, this solution, that is, the final determination process will be described with reference to FIG.

As shown in FIG. 8, the feature amount extracting section 93 has a low-resolution image memory 110 and a specific resolution converting section 105.
The RGB image data converted to a specific resolution is temporarily stored in the low-resolution image memory 110.
Now, in the frame determination process, the type of the frame mask used when it is determined that the specific image is likely to be included in the image is used to determine the angle at which the specific image is arranged in the frame determination stage. be able to. In addition, at the stage of applying a frame mask by performing a shift or the like on an image, it is possible to give an estimate of the coordinate information of the specific image. The CPU 98 is configured with hardware so that it can access the low-resolution image memory 110 (not shown). When the CPU 98 recognizes the image as a specific image in the secondary determination, based on the position and rotation angle information of the frame mask, Low-resolution image memory 110 by CPU 98
By accessing the corresponding address, it is possible to obtain, for a characteristic portion of the specific image, structural information on a printing net, macro information constituting an image such as an edge, more detailed color information, and the like. By performing the final determination based on these pieces of information after the secondary determination, the possibility of an erroneous determination can be greatly reduced.

Next, processing according to the determination result will be described.

The CPU 98 controls the engine interface 95 based on the provisional judgment result and the final judgment result among the judgment processes described above, and manages the image forming process in the image forming section 2A.

FIG. 21 is a flowchart showing a control process based on the provisional judgment result and the final judgment result. However, in order to facilitate the description, the description will be made from the time when the image reading apparatus 1 is instructed to read an image.
To be used together.

First, the CPU 98 issues a control command to the image reading device 1 via the scanner interface 91, and instructs the start of reading (S21). Next, CPU
98 sets the feature amount extraction unit 93 and issues an instruction to start recognition of a specific image with respect to image data to be input (S22). Next, the CPU 98 reads an image of one page based on information input from the scanner interface 91 (particularly, the amount of image data returned from the image reading apparatus 1 and not yet transferred by the GET DATABUFFER STATUS command described above). It is determined whether or not (S23). If 1
If it is determined that the image data for the page has been read, the image forming unit 2A is activated via the engine interface 95 based on the process described above (S2).
4). After starting the image forming unit 2A, the CPU
98 waits for a result of the provisional judgment, and checks whether or not a specific image is detected in the image data read by the provisional judgment (S25). If no specific image is detected at this point, the process immediately jumps to the end.

On the other hand, when a specific image is detected in the image data read by the tentative determination, the print control signal PRINT (see FIG. 20) output from the engine interface 95 based on the process described above is output. Immediately O
The state is set to the FF state (S26). Thereby, the image forming unit 2
A stops the operation of the drive source and the like once started and returns to the standby state.

Next, the CPU 98 makes a secondary judgment and a final judgment based on the feature amount of the image extracted by the feature amount extracting section 93, and determines whether or not the input image data contains a specific image with high accuracy. (S27). If the specific image is not detected in the final determination, the image forming unit 2A is activated again and printing is continued (S29). On the other hand, if the specific image is detected in the final determination, the CPU 9
8 directly accesses the page memory 94 to perform predetermined processing on the image (S28). When the processing is completed, the image forming unit 2A is activated again to continue printing (S2).
9).

Image data, such as business documents and paintings, that have little or no similarity to the specific image is determined by the tentative determination to not include the specific image. High-speed copying can be performed without stopping the unit 2A.

Next, the image processing when a specific image is detected in the final judgment will be described.

FIGS. 22A and 22B are image processing diagrams showing the contents of image processing when a specific image is detected in the final determination. Hereinafter, the processing for preventing forgery will be described with reference to FIGS.

The CPU 98 is configured to be readable and writable with respect to the page memory 94.
4 can be accessed to obtain or change image data. When a specific image is detected in the final determination by the above-described procedure, the CPU 98 directly rewrites image data in the page memory 94 to perform forgery prevention processing. With this configuration, the forgery prevention processing can be changed in any way by software.

The page memory 94 stores image data binarized by the above-described image processing of the copying controller 90. FIG. 22A shows the image data of the image forming apparatus. 2 shows an image when output is performed. In FIG. 22, each grid indicates a place where dots are arranged when forming an image, 150 indicates a main scanning direction, and 151 indicates a sub-scanning direction.

In the forgery prevention processing in the present embodiment, pixels arranged in each lattice shown in FIG. 22A are thinned out alternately by half in the main scanning direction 150 by one line. As a result, the number of pixels is reduced to 1/4 of that before processing (only the hatched pixels in FIG. 22A remain). In the case of a line in which pixels are halved in actual processing, CP
Data is accessed in units of words by U98, left-shifted in units of 1 bit, and the bit state when the number of shifts is an odd number is written to the corresponding bit of a separately prepared byte register. This result is stored in the page memory 9
If the image data is copied sequentially from the upper address of No. 4, the image data of the page memory 94 will be finally arranged as shown in FIG.

Since the CPU 98 knows how the original image size has changed by the thinning process, the CPU 98 controls the image forming unit via the engine interface 95 based on the number of pixels reduced according to the change in the image size. 2
In A, the number of pixels in the main scanning direction and the number of lines in the sub-scanning direction are set again. This is because the serial communication line 145 connecting the engine interface 95 and the image forming unit 2A has already been described with respect to the engine interface 95 connecting the copying controller 90 and the image forming unit 2A.
(See FIG. 20). In this state, by outputting the print control signal PRINT (see FIG. 20) from the engine interface 95 in accordance with the procedure already described, an image reduced in half in both the main scanning direction and the sub-scanning direction is output.

By performing the reduction process on the specific image in this manner, the image actually copied is printed smaller than the actual image, but if the actual size is changed by 25% in area, At first glance you can see that it is a fake. Of course, the reduction ratio may be other than the value shown here, and it is also possible to enlarge instead of reducing. The point is that when a specific image is detected, it is meaningful to copy at a scaling factor that can be clearly discriminated from the real image (common sense) and prohibit copying in a 1: 1 size.

As described above in detail, in the present embodiment, the color information is used for recognizing the specific image. It cannot be proved that there is absolutely no similar non-specific image. " In other words, there is always a risk of erroneous determination that a non-specific image is determined as a specific image, and it is not possible to copy an image that can be copied originally, or the image is significantly modified and cannot be used for its intended purpose. And other problems may occur.

However, this problem can be solved by adopting the scaling process described above. In general, the entire image of a color image is important, and there are very few cases where the copy size is particularly important. As a manuscript requiring an accurate size, for example, a drafting drawing is typical, but a monochrome copy is sufficient for this copy. However, specific images, such as banknotes, fall under this exception.If they are color and have the correct dimensions, they can be construed as counterfeits, and with a certain magnification, counterfeits can be easily identified. it can. That is, when a specific image is recognized, the image is scaled and copied so that the specific image can be completely recognized as a counterfeit, and a general image is erroneously determined to be a specific image. But the damage to the user can be kept to a minimum.

The above-described forgery prevention processing adopted in the present embodiment is a simple method on the premise that the CPU 98 can perform high-speed processing, but the advantage of performing forgery prevention processing by software can be further utilized. . For example, the final determination of a specific image is performed by a neural network as described in detail, and a multi-level signal is output from a node of this output layer. Since these outputs are indices indicating the likeness of the specific image, it is, of course, possible to form an image by changing the magnification according to the likeness of the specific image. Further, with the configuration shown in the present embodiment, the image data stored in the page memory 94 can be directly changed by the CPU 98, so that not only the scaling process but also any forgery prevention processing is performed only by software change. It is possible.

(Embodiment 2) Hereinafter, an image copying system according to Embodiment 2 of the present invention will be described with reference to the drawings. In the first embodiment, the copying controller 90 built in the image forming apparatus 2 has a function of recognizing a specific image. In the second embodiment, the image reading apparatus 1
Has a function of recognizing a specific image.

FIG. 1 also shows an image copying system according to Embodiment 2 of the present invention. That is, each component shown in FIG. 1 is the same as that of the first embodiment, but some functions are different. In FIG. 1, an image reading apparatus 1 reads a document and outputs digital color image data, and detects whether or not the read image includes a specific image such as a bill prohibited from being copied. The image forming apparatus 2 forms a color image based on image data transferred from the outside. A copying controller 90 (not shown) is stored inside the image forming apparatus 2 and processes color image data output from the image reading apparatus 1 to generate print data. 2A (see FIG. 6) is controlled. The cable 3 connects the image reading apparatus 1 and the image forming apparatus 2 to each other. Image data, commands, and specific image detection results are bidirectionally communicated between the apparatuses by the cable 3.

The mechanical configuration and operation of the image reading apparatus 1, the configuration and operation of the image forming apparatus 2, the interface between the copying controller 90 and the image forming section 2A, the feature extraction and determination algorithm of the specific image, and the tentative determination And items such as processing according to the judgment result of the final judgment,
The description is omitted because it is equivalent to the first embodiment. The different point is the configuration of the reading controller of the image reading apparatus 1.

FIG. 23 is a block diagram showing a reading controller of the image reading apparatus 1 according to Embodiment 2 of the present invention.

In FIG. 23, image forming apparatus 2, stepping motor 8, image sensor 20, amplifier / A / D
Converter 24, shading correction unit 25, line correction unit 26, resolution conversion unit 27, color processing unit 28, buffer 2
9, interface unit 30, motor control unit 32, CPU
The reference numeral 33 and the system bus 34 are the same as those shown in FIG. 93 is a feature amount extraction unit,
105 is a specific resolution conversion unit, 106 is a feature amount calculation unit, 1
07 is a buffer. The feature amount extraction unit 93 divides the read image data into predetermined blocks, and performs a statistical process for each block to extract a local feature amount. The specific resolution conversion unit 105 converts the read image data into a fixed resolution, for example, 75 dpi, regardless of the reading resolution designated by the image forming apparatus 2. The feature amount calculation unit 106 calculates the local feature amount of the image by performing a statistical process of counting the number of pixels having a specific tint with respect to the image data converted to a certain resolution by the specific resolution conversion unit 105. calculate. The buffer 107 temporarily stores the local feature calculated by the feature calculator 106. In the present embodiment, the local feature value of the image extracted by the feature value extracting unit 93 is transferred to the image forming apparatus 2 via the interface unit 30 and the image forming apparatus 2 includes the specific image in the image. It is determined whether or not. As described above, the point that the reading controller of the image reading apparatus 1 includes the feature amount extracting unit 93 is different from the first embodiment.

Next, the feature value extracting section 93 will be described with reference to FIG. FIG. 24 is a block diagram showing in detail the feature amount extraction unit 93 according to Embodiment 2 of the present invention. Hereinafter, the feature amount extraction unit 93 will be described in detail with reference to FIGS.

In FIG. 24, the line correction section 26, interface section 30, CPU 33, feature quantity extraction section 93, specific resolution conversion section 105, and buffer 107 are the same as those in FIG. The color counter 111, the template selection unit 112, the template storage memory 113, the main / sub-pixel counter 115, and the interrupt signal line 116 are the same as those in FIG.

The schematic operation and the like of the feature amount extracting unit thus configured will be described. Specific resolution converter 10
Reference numeral 5 converts the input image data into a fixed resolution regardless of the reading resolution specified by the image forming apparatus 2. The image data converted to a certain resolution by the specific resolution conversion unit 105 is temporarily stored in the low-resolution image memory 110. The characteristic color counter 111 generates characteristic vector data by performing statistical processing of counting the number of pixels included in a predetermined range (= similar colors) for a plurality of predetermined characteristic colors. Template selection unit 1
12 compares the feature vector data generated by the feature color counter 111 with a plurality of templates prepared in advance,
Select the template with the closest Euclidean distance.
The template storage memory 113 stores a plurality of templates used by the template selection unit 112 for comparison with the feature vector. The range in which the characteristic color is counted as the characteristic color by the characteristic color counter 111 and the plurality of templates stored in the template storage memory 113 are set by the CPU 33. CPU 33
Has acquired template information from the image forming apparatus 2 via the interface unit 30. The buffer 107
The number of the template selected by the template selection unit 112 and the Euclidean distance between the feature vector data and the template are stored. These feature amounts stored in the buffer 107 are taken out by the CPU 33, sent to the interface unit 30, and sent to the image forming apparatus 2 via SCSI. The main / sub-pixel counter 115 counts the number of input image data in the main scanning direction and the sub-scanning direction, and outputs an interrupt signal INTR to the CPU 33 every time the count reaches a predetermined count.

Next, regarding the specific resolution conversion unit 105,
This will be described in detail with reference to FIGS. 24 and 23.

The input to the specific resolution conversion unit 105 is performed before the resolution conversion unit 27. The reason will be described below. The line correction unit 26 corrects the distance between the RGB lines because the position of the line sensor array of each color differs in the sub-scanning direction. At this point, the resolution in the main scanning direction remains output from the image sensor, and no processing is performed. That is, as far as the main scanning direction is concerned, the resolution of the optical system assumed in this embodiment is 60.
Image data having a resolution of 0 dpi is output.

As described above, at the time of output from the line correction unit 26, the resolution in the main scanning direction is always 600d regardless of the designation of the reading resolution by the image forming apparatus 2.
pi, so that this is fixed at a certain resolution, for example, 7
The conversion to 5 dpi can be performed by a single processing system which is also parameter invariant. If the output of the resolution conversion unit 27 is used to convert the data to a fixed resolution, for example, 75 dpi, image data of various resolutions must be handled, and the hardware becomes complicated. As described above, the feature amount extraction unit 93 is provided in the image reading device,
By obtaining data from the part where the resolution is constant,
The circuit configuration can be simplified.

As described above, the image data in the main scanning direction always has a resolution of 600 dpi, but in the present embodiment, the fixed pixel thinning rate is 2 in the main scanning direction, and the image data of 600 dpi is Once 300dp
Converted to i. By performing the thinning process in this way,
The amount of image data to be processed thereafter can be significantly reduced. The resolution in the sub-scanning direction is converted to a resolution of 150 dpi to 75 dpi by applying known linear interpolation.

Next, the image data obtained by the thinning process is converted to a constant resolution of 75 dpi in both the main scanning and sub-scanning directions by averaging. First, 300 dpi in the main scanning direction × 75 dpi in the sub-scanning direction by the thinning process.
When converted to i, 4 × 1 pixel values are averaged using four pixels in the main scanning direction and pixels for one line in the sub-scanning direction. Also, the main scanning direction 300
In the case of conversion into dpi × sub-scanning direction 150 dpi, the value of 4 × 2 pixels is averaged using four pixels in the main scanning direction and pixels for two lines in the sub-scanning direction.

As described above, in the present embodiment, the output of the line correction unit 26 is converted to a fixed resolution by the thinning process and the averaging process, but at least image data in the main scanning direction is converted. The averaging process is always performed. In the present invention, the RG obtained from the image reading device is used.
An image feature amount for recognizing a specific image is obtained based on the B image data. However, in the image reading apparatus 1, there are limitations on the position accuracy of the image sensor, the driving accuracy of the carriage, and the like. Taste information may not be correctly reflected. Since there is a possibility that an erroneous image density is stochastically generated at an edge portion by only the thinning process, in the present embodiment, when converting to a fixed resolution, the thinning process and the averaging process are mixed, and at least the main scanning is performed. An averaging process is always performed for the direction.

With the above processing, image data of a specific resolution of 75 dpi is obtained in both the main scanning and sub-scanning directions. The resolution of 75 dpi is higher than the optical resolution of 600 dpi of the image reading apparatus 1 of the present embodiment. It is a sufficiently small value. By recognizing the specific image using the image data converted to a resolution sufficiently smaller than the optical resolution of the image reading device 1, it is possible to recognize the specific image substantially without depending on the reading resolution. it can. Since this can substantially eliminate the limitation of the resolution when recognizing the specific image, for example, it is possible to copy the specific image for which copying is prohibited by performing a reduced copy once and then performing an enlarged copy again. Malicious actions can also be prevented.

Next, the operation of the feature quantity extracting section 93 in the present embodiment will be described with reference to FIG.

The specific resolution conversion unit 105 outputs 75d
The RGB image data converted to a fixed resolution of pi is temporarily stored in the low-resolution image memory 110. The RGB image data stored in the low-resolution image memory 110 is cut out in blocks of a predetermined size, and sent to the characteristic color counter 111 as RGB point sequential signals. The size of the block is set to, for example, 50 × 50 pixels (2500 pixels). The characteristic color counter 111 counts the number of pixels falling within a range of RGB values determined in advance as characteristic colors for the input RGB image data. This count range is determined based on information previously obtained from the image forming apparatus 2 through the interface unit 30 based on the CP.
It is set in the characteristic color counter 111 by U33, but if it is assumed that the specific image to be recognized does not change, it may be fixedly stored in some storage unit (not shown) of the image reading device 1.

In the present embodiment, three different colors included in a specific image are defined as characteristic colors, and the number of pixels determined to be characteristic colors is counted for each block. By this counting, the values of the plurality of pixels are statistically histogrammed. When the counting of the characteristic colors of one block is completed, the result is transferred to the template selecting unit 112. By the way, what is output from the characteristic color counter 111 is a statistic which counts the number of a plurality of characteristic colors present in the 50 × 50 pixel block. Since the number of characteristic colors is 3, this can be regarded as outputting a three-dimensional characteristic vector. That is, the feature color counter 111 generates a feature vector.

The template selection unit 112 compares the feature vector generated by the feature color counter 111 with a plurality of templates stored in the template storage memory 113 based on the three-dimensional Euclidean distance, and determines the closest template. At the same time, the template number and the three-dimensional Euclidean distance are stored in the buffer 107. The nearest neighbor template number and the three-dimensional Euclidean distance serve as indices indicating the similarity between the input image data and the specific image.

The total number of pixels processed by the characteristic color counter 111 is counted and managed by the main / sub-pixel counter 115. When the counted number of pixels processed reaches a predetermined amount, the main / sub-pixel counter 115 starts counting. The sub-pixel counter 115 is a CPU 33
Generates an interrupt signal INTR. In response to the interrupt signal INTR, the CPU 33 extracts the contents of the buffer 107 and controls the interface unit 30 to control the nearest neighbor template number stored in the buffer 107,
The three-dimensional Euclidean distance is output to the image forming apparatus 2.
The details of the communication with the image forming apparatus 2 will be described later.

The other components of the feature amount extraction unit 93 are:
The operations of the characteristic color counter 111 and the template selection unit 112 are the same as those in the first embodiment, and thus the description is omitted.

FIG. 26 is a block diagram showing a copying controller 90 for processing image data printed by the image forming apparatus 2 and controlling the image forming section 2A. Although the image reading apparatus 1 has been described as being directly connected to the image forming apparatus 2 (via the interface unit 30), the image reading apparatus 1 is actually connected to the copying controller 90. In this embodiment, the copying controller 90 is built in the image forming apparatus. FIG.
6 and FIG. 6, the present embodiment is different from the first embodiment in that the copying controller 90 does not include the feature amount extracting unit 93. Hereinafter, the configuration of the copying controller 90 will be described with reference to FIG.

Referring to FIG. 26, copy controller 90
Is built in the image forming apparatus 2. The scanner interface 91 outputs a command to the image reading device 1 and receives image data. The image processing unit 92 processes the image data input from the image reading device 1 to generate data in a format in which an image can be formed. The page memory 94 stores at least one image data processed by the image processing unit 92. The page memory 94 stores binarized image data for the four primary colors C (cyan), M (magenta), Y (yellow), and K (black) for printing. The engine interface 95 outputs the image data stored in the page memory 94 to the image forming unit 2A. Each module in the copying controller 90 transmits and receives data using the system bus 96. Working memory 9
Reference numeral 7 is used as a work area in image processing and recognition of a specific image. The CPU 98 controls each module via the system bus 96 and controls the image reading device 1.
In a plurality of stages, it is detected whether or not a specific image is included in the image data based on the feature amount of the image transferred from.
All the CPUs 98 operate according to programs stored in the ROM 99.

Next, a process of processing image data input from the image reading apparatus 1 will be described with reference to FIG.

The CPU 98 has a scanner interface 9
A predetermined control command is output to the image reading apparatus 1 through the control unit 1 (details of the control command will be described later).
The image reading device 1 reads a document in accordance with the transferred control command and outputs color image data and local feature amounts of the image. The output image data and local feature amount are received by the scanner interface 91, the image data is sent to the image processing unit 92, and the feature amount is temporarily received by the CPU 98 and then copied to a predetermined area of the working memory 97. Is done. The image processing unit 92 performs color processing and the like on the color image data, and outputs
Is converted to a data format that can be formed by. The image data processed by the image processing unit 92 is stored in the page memory 94.

The CPU 98 determines at a plurality of levels whether or not a specific image is present in an input image based on the feature amount transferred from the image reading device 1. A three-stage determination of a secondary determination and a final determination is performed.

Now, the color image data is stored in the page memory 9.
When one image is stored in the CPU 4, the CPU 98 controls the engine interface 95 to instruct the image forming unit 2A to start the operation, but after instructing the operation to start, the specific image may be included in the temporary determination. If it is determined that
The operation start instruction already output to the image forming unit 2A is suspended. Due to this suspension, the operation of the image forming unit 2A is temporarily stopped. Since the provisional determination is performed at a very high speed as described later, an image is not actually formed in the image forming process of the image forming apparatus described above.

If it is determined in the tentative determination that the specific image is not included in the read image, the above-mentioned holding is not performed, and the color image data in the page memory 94 is output via the engine interface 95. Immediately, printing is performed in the image forming unit 2A. Therefore, when the specific image is not detected in the tentative determination, an image can be formed at high speed.

On the other hand, if it is determined in the tentative judgment that the specific image is included in the read image, a more detailed check is performed to obtain a final judgment result. If a specific image is detected in the final determination, the CPU 98 directly rewrites the image data in the page memory 94 to perform processing for preventing forgery. Since this processing is performed on the image data stored in the page memory 94, for example, a predetermined character string or pattern can be overwritten at high speed.
Further, as will be described in detail later, reduction by simple thinning or the like can be easily performed.

If the specific image is not detected in the final judgment, the CPU 98 releases the hold instructed to the engine interface 95. As a result, image data that has not been subjected to forgery prevention processing is printed by the image forming unit 2A.

Next, the transfer of image data and feature values will be described.

In the image reading apparatus 1, as described above, the local feature amount for the image divided into blocks,
That is, the feature vector output from the feature color counter 111, and the template number and the feature vector / template distance output from the template selection unit 112 are temporarily stored in the buffer 107 shown in FIG. When storage in the buffer 107 has been completed for a predetermined amount of blocks, the main / sub-pixel counter 115 outputs the interrupt signal I
An NTR is generated to notify the CPU 33 that significant data is stored in the buffer 107. The procedure for transferring the local feature value extracted by the image reading apparatus 1 to the copying controller 90 of the image forming apparatus 2 will be described below.

FIG. 25 is a sequence diagram showing a procedure for a command exchanged between the copying controller 90 and the image reading apparatus 1 and data to be transferred according to the second embodiment of the present invention. Hereinafter, transmission and reception of data by the SCSI command will be described in detail with reference to FIG. A solid arrow in the drawing indicates that a command has occurred in that direction, and a broken arrow indicates that data is sent in that direction. In the following description, for simplicity, S
Although the CSI will be described as an example, the same procedure can be adopted for all other interfaces if the host computer and the image reading apparatus can perform bidirectional communication.

When reading image data, first, the copying controller 90 sends the image reading device 1
Issue an EST UNIT READY command. Upon receiving this command, the image reading device 1
The status of the image reading device such as Y or READY is returned to the copying controller 90 (S200). The copy controller 90 waits until the returned state becomes READY.
Issue a TEST UNITREADY command periodically. When the image reading device 1 returns READY in response to the TEST UNIT READY command, the copying controller 90 determines that the image reading device 1 is in a readable state, and issues a MODE SENSE command (S201). Upon receiving this command, the image reading device 1 receives an operation status of an operation panel (not shown), that is, whether or not a copy start instruction has been issued (copy start key information), or what read mode has been selected. The information about the user operation is output to the copying controller 90. Copy controller 90
Periodically outputs a MODE SENSE command until copy start is instructed by the copy start key information,
The information of the operation panel is continuously obtained from the image reading device 1.

If it is determined that the copy start is instructed by the copy start key information, the copy controller 90
Issues a MODE SELECT command. With this command, the copying controller 90 causes the image reading device 1
Is passed to the control parameter (S202). The control parameters include, for example, information as to whether or not to use the automatic document feeder (ADF) in the image reading device 1;
The information includes information such as a unit system when designating a reading range and the like, and further includes a parameter for selecting data output by the image reading apparatus 1 in a scanning operation to be performed in the future. That is, the user selects whether to read the document and output the image data, read the document and output the local feature amount, or output both.
In the present embodiment, selection is made so as to output both the image data and the local feature amount of the image.

Next, the copying controller 90 issues a SET WINDOW command to the image reading device 1. Following this command, the copying controller 90 passes the image reading conditions to the image reading device 1 (S203). The image reading conditions include information such as an image reading start position, a reading range (image size), and an image reading resolution. In the present embodiment, the reading resolution is set to 600
The dpi and the reading range are set to, for example, the entire LETTER size from the head of the readable position.

If it is specified in step 202 that at least the local feature of the image is to be output, the copying controller 90 issues a SEND command to the image reading device 1 and subsequently issues a SEND command to the image reading device 1. The feature color count range and the template are transferred to be set in the feature amount extraction unit 93 (see FIG. 24) (S204).

Next, the copying controller 90 issues a SCAN command to the image reading apparatus 1 (S
205). Thereby, the image reading device 1 is driven by the driving source 8
Rotation (see FIG. 2) is started to prepare for image reading.

Next, the copying controller 90 sends a GET PIXEL NUMBE to the image reading apparatus 1.
Issue an R command. Upon receiving this command, the image reading device 1 calculates the actual number of pixels per line, the amount of data, and the like from the image size and the reading resolution received in step 203, and returns the result to the copying controller 90 (S206). ). SET WI in this way
For the reading conditions specified by the NDOW command,
By returning the actual setting value on the image reading device 1 side, for example, when the specified value of the reading range requested by the copying controller 90 is higher than the accuracy handled by the image reading device 1, the matching between the devices can be achieved. (The copy controller 90 follows the value returned from the image reading device 1).

Next, the copying controller 90 sends a GET DATA BUFFER to the image reading device 1.
Issue a STATUS command. Upon receiving this command, the image reading device 1 determines the amount of the image data and the amount of the feature not yet transferred to the copying controller 90.
(S207). In this process, only the remaining amount of the image data may be transferred.

Next, when the copying controller 90 has instructed the image reading apparatus 1 to output at least image data in step 202,
(1) A command is issued, and a predetermined amount of image data is received from the image reading device 1 (S208).

Next, if the copying controller 90 has instructed the image reading device 1 to output at least the local feature of the image in step 202, the
An AD (2) command is issued, and the local feature amount of the image is received from the image reading device 1 (step 209).

The processing from step 207 to step 209 is repeated until it is determined in step 207 that there is no remaining data to be transferred.

As described above, in the present embodiment, the transfer of the image data and the local feature of the image is alternately repeated. For example, considering a LETTER size document, the local feature amount of the image is about 600 bytes, and if the image is to be transferred collectively, it must be stored in the buffer of the image reading apparatus 1 until the image reading is completed. However, if the document size increases, it must be expanded to the maximum document size. However, by alternately outputting the image data and the local feature amount of the image, the buffer on the image reading apparatus 1 side needs only about 40 bytes. This is a capacity that can be called a register rather than a memory, and hardware can be easily realized. Further, by transferring the image data and the local feature amount of the image alternately, the copying controller 90 can sequentially process the acquired local feature amount of the image. There is also an effect that the required time until a specific image is determined can be substantially reduced.

According to the procedure described above, the image data and the local feature amount of the image are transferred from the image reading device 1 to the copying controller 90.

Next, the process of determining a specific image based on the local feature of the image passed to the copying controller 90 will be described with reference to FIG.

The local characteristic amount of the image output from the image reading device 1 is fetched by the scanner interface 91, then fetched by the CPU 98, and copied to a predetermined area of the working memory 97. The CPU 98 determines the specific image included in the image in a plurality of stages based on the feature amount data in the work memory 97.

The process of these determinations is the same as the method described in detail in the first embodiment, and a description thereof will not be repeated.

The configuration described in detail in the present embodiment has the following great merits other than that described in the first embodiment.

First, since the feature amount extracting unit 93 for determining a specific image is provided on the image reading apparatus 1, it is possible to cope with an apparatus form in which image data is output from the image reading apparatus 1 in a compressed format. Is raised. In general, an irreversible compression method such as JPEG is often used for color image data. The image compression method using such image correlation can realize a high compression rate, but does not reproduce the pixel density at a microscopic level in pixel units. Accordingly, when an image reading apparatus compresses an image and outputs the compressed image, and recognizes a specific image based on the image decompressed by the copying controller 90, the apparatus is described in detail in the first embodiment. This is disadvantageous for image recognition using color. However, this problem does not occur in the present embodiment in which the image reading device 1 extracts a feature amount of an image before performing image compression.

In general, a high-speed CPU is mounted on a controller of an image forming apparatus, particularly a color printer that prints image data output from a host computer, but the image reading apparatus 1 controls the operation of the apparatus. In many cases, a CPU of the order is mounted. Embodiment 2
The feature amount extraction unit 93 of the image reading apparatus 1 described above can be realized in a relatively small scale as hardware (the gate size of the gate array is 10,000 gates or less), and the CPU itself does not have any load during the feature amount extraction process. Does not occur. On the other hand, the controller (here, the copying controller 90) determines the specific document using the feature amount transferred from the image reading apparatus 1, but this processing is performed at high speed by using the entire controller configuration of the color printer. CPU can be used. In this way, it is possible to mount a forgery prevention function without increasing the price of the total system.

In the first and second embodiments, the method of using tint has been described as a method of recognizing a specific image. However, as a method of recognizing a specific image, for example, a distribution of edge amounts may be used. It may be performed by detecting a specific shape. In the first and second embodiments, a copy-only controller is described as a copy controller. However, this function may be included in a controller function built in a color printer or the like. As for the processing for preventing forgery, the configuration and procedure for directly processing the image data in the memory are disclosed. However, for example, the image may be processed by using the components of the copying controller.
For example, in a copy controller, if a resolution conversion unit is provided downstream of the page memory, it is of course possible to perform scaling processing using the resolution conversion unit. In addition, a processing method such as changing the image density can be applied as long as the specific image and the real object can be sufficiently determined.

[0231]

As described above, the image copying system according to the first aspect of the present invention has a reading controller, and scans an original under the control of the reading controller to output color image data. An image forming apparatus that has a copying controller and an image forming unit, and that inputs color image data from the image reading device and forms a color image in the image forming unit based on the control of the copying controller. An image copying system comprising: a storage unit for storing color image data input from an image reading device; and a plurality of stages of input color image data including at least two stages of provisional determination and final determination. A specific image detecting section for detecting a specific image included in the image, and a storage section based on a detection result of the specific image detecting section. And a control unit that controls whether or not to cause the image forming unit to form the color image data, the specific image detection unit can determine whether the image is a specific image in a stepwise manner. When it is determined that the image is not a specific image, the formation of a color image can be started immediately, the printing speed of an image having low similarity to the specific image can be substantially increased, and based on an accurate final determination, The advantageous effect that duplication of a specific image can be prevented is obtained.

According to the image copying system of the present invention, in the image copying system of the present invention, when the color image data of one image or more is stored in the storage unit, the control unit performs the image forming. Output an instruction signal to instruct the image forming unit to start image formation, and when the specific image detection unit determines in the tentative determination that there is a specific image, cancels the instruction signal and outputs a hold signal, thereby outputting 1 to the storage unit. By activating the image forming unit as soon as color image data for an image or more is stored, it is possible to speed up the recording of an image when it is determined that the image is not a specific image in the tentative determination. If an image having a high similarity to the specific image is detected in the tentative determination after the activation of the forming unit, a signal for suspending image formation is output to stop the operation of the image forming unit and prevent duplication of the specific image. Advantageous effect that it is possible to obtain.

According to the image copying system of the third aspect, in the image copying system of the second aspect, when the specific image detecting section determines in the final determination that there is no specific image, the control section outputs the hold signal. By canceling and outputting the instruction signal again, the advantageous effect that the image forming unit can continue the image formation can be obtained.

According to the image copying system of the fourth aspect, in the image copying system of the second aspect, the specific image detecting section is provided before the image forming section starts visualization processing based on color image data. By outputting the result of the provisional determination, it is possible to prevent an image from being formed (in a visible form) before the result of the provisional determination is obtained, thereby preventing wasteful consumption of color materials and the like. An advantageous effect is obtained.

According to the image copying system of the present invention, there is provided an image reading apparatus which has a reading controller, scans an original under the control of the reading controller, and outputs color image data. An image forming apparatus, comprising: an image forming unit that inputs color image data from an image reading device under control of a copying controller to form a color image in the image forming unit; Is a storage unit for storing at least one image of color image data input from the image reading device, and detects a specific image included in the input color image data by at least two-stage determination including temporary determination and final determination A specific image detection unit that performs color conversion stored in a storage unit based on a detection result of the specific image detection unit. A control unit that processes the image data and causes the image forming unit to form a color image based on the processed color image data, so that when the image is determined to be the specific image, the color image data is processed, and the specific image is copied. Is obtained.

According to the image copying system of the sixth aspect, in the image copying system of the fifth aspect, when the specific image detecting section determines that the specific image is present in the final determination, the control section stores the information in the storage section. By performing the predetermined processing on the stored color image data, an advantageous effect is obtained in that the duplication of the specific image can be prevented without using special image processing hardware.

According to the image copying system of the present invention, in the image copying system of the present invention, when the specific image detecting section determines that the specific image is present in the final determination, the control section stores the image in the storage section. By performing scaling processing on the stored color image data, it is possible to prevent a specific image from being duplicated, and even if a non-specific image is erroneously determined to be a specific image, the duplicated copy is used. This has the advantageous effect of avoiding the situation of not becoming the same.

According to the image copying system of the present invention, there is provided an image reading apparatus which has a reading controller, scans an original under the control of the reading controller and outputs color image data, and a copying controller. An image forming apparatus having an image forming unit and inputting color image data from an image reading device under the control of a copying controller to form a color image in the image forming unit. The controller has a specific image detection unit that detects a specific image included in the read color image data, and the copying controller has a storage unit that stores the color image data input from the image reading device, and a specific image detection unit. Whether to cause the image forming unit to form the color image data stored in the storage unit based on the detection result of And a control unit for controlling the image data, the specific image can be compressed and transmitted from the image reading device to the image forming device, so that the transmission efficiency can be improved, and the color image can be transmitted to the image forming unit. Since it is determined by the high-speed control unit of the copying controller whether or not to form, it is possible to obtain an advantageous effect that forgery of a bill or the like can be prevented without increasing the price.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a general image copying system.

FIG. 2 is a schematic cross-sectional view illustrating an image reading apparatus that forms the image copying system of FIG. 1;

FIG. 3 is a schematic sectional view showing an internal structure of a carriage of the image reading apparatus.

FIG. 4 is a block diagram illustrating a reading controller of the image reading apparatus.

FIG. 5 is a configuration diagram showing a mechanical configuration of an image forming apparatus constituting the image copying system of FIG. 1;

FIG. 6 is a block diagram showing a copying controller constituting the image forming apparatus of the image copying system according to the first embodiment of the present invention;

FIG. 7 is a block diagram showing details of an image processing unit and a feature amount extraction unit of the copying controller;

FIG. 8 is a block diagram showing the configuration of a feature amount extraction unit in more detail;

FIG. 9 is a block diagram showing a characteristic color counter.

FIG. 10 is a data structure diagram showing a structure of data stored in a buffer.

FIG. 11 is a flowchart showing the operation of a template selection unit.

12A is a relationship diagram showing a relationship between a template and a specific image. FIG. 12B is a relationship diagram showing a relationship between a template and a specific image. FIG. 12C is a relationship diagram showing a relationship between a template and a specific image. Diagram showing the relationship between the image and the specific image

FIG. 13 is a data configuration diagram showing a data configuration in a working memory.

14A is an image diagram showing an image of TN (n) and D (n) given to each block of a specific image. FIG. 14B is a diagram showing TN given to each block of a specific image.
(N) Image diagram showing images of D (n) (c) TN given to each block of a specific image
Image diagram showing images of (n) and D (n)

15A is a frame mask structure diagram showing the structure of a frame mask. FIG. 15B is a frame mask structure diagram showing the structure of a frame mask. FIG. 15C is a frame mask structure diagram showing the structure of a frame mask.

FIG. 16 is a flowchart showing processing contents for one frame in frame processing;

FIG. 17A is a diagram illustrating rotation angle correction in a secondary determination. FIG. 17B is a diagram illustrating rotation angle correction in a secondary determination.

FIG. 18 is a diagram illustrating a relationship between a recognition process and a frame, a block, and a recognition process in a secondary determination.

FIG. 19 is a sequence diagram showing a processing procedure for commands exchanged between the copying controller and the image reading apparatus and data to be transferred;

FIG. 20 is an interface diagram showing details of an engine interface for connecting the copy controller and the image forming unit;

FIG. 21 is a flowchart showing a control process based on a temporary determination result and a final determination result.

FIG. 22 (a) is an image processing diagram showing the content of an image processing process when a specific image is detected in the final determination. FIG. 22 (b) shows the content of the image processing process when a specific image is detected in the final determination. Image processing diagram

FIG. 23 is a block diagram illustrating a reading controller of the image reading apparatus according to the second embodiment of the present invention;

FIG. 24 is a block diagram showing in detail the structure of a feature amount extraction unit according to the second embodiment of the present invention;

FIG. 25 is a sequence diagram showing a procedure of a command exchanged between the copying controller and the image reading apparatus and data to be transferred according to the second embodiment of the present invention;

FIG. 26 is a block diagram illustrating a copy controller that processes image data printed by the image forming apparatus and controls an image forming unit;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image reading device 2 Image forming device 2A Image forming part 3 Cable 6 Document glass 7 Carriage 8 Drive source (stepping motor) 9 Drive pulley 10 Timing belt 11 Belt 12 Follower pulley 13 Document 14 Document cover 15 Support part 16 Reference acquisition position 17 Lamp 18 Aperture 19a, 19b Reflection mirror 20 Image sensor 21 Imaging lens 24 Amplifier / A / D converter 25 Shading correction unit 26 Line correction unit 27 Resolution conversion unit 28 Color processing unit 29 Buffer 30 Interface unit 32 Motor control unit 33 CPU 34 System Bus 51 Photoconductor 52, 53, 54 Photoconductor Transport Roller 56 Photoconductor Position Detection Mark 57 Photoconductor Position Detection Sensor 58 Seam 59 Charger 60 Exposure Optical System 61 K, 61 Y, 61 M, 61 C Device 62 Pre-intermediate transfer static eliminator 63 Intermediate transfer roller 64 Photoconductor cleaning device 65 Static eliminator 66 Exposure light beam 67K, 67Y, 67M, 67C Sleeve roller 68K, 68Y, 68M, 68C Separation / contact cam 69 Intermediate transfer member 70, 71, 72 Conveyance roller 73 Intermediate transfer member position detection mark 74 Intermediate transfer member position detection sensor 75 Pre-transfer charger 76 Density sensor 77 Paper transfer roller 78 Intermediate transfer member cleaning device 79 Recording paper 80 Recording paper cassette 81 Feeding roller 82 Paper conveyance Road 83 Slip roller 84a Registration roller 84b Follower roller 85 Fixing unit 86 Heat roller 87 Pressure roller 88 Density sensor 90 Copy controller 91 Scanner interface (scanner I / F) 92 Image processing unit 93 Feature extraction unit (specific image detection unit) 94 page memory (storage unit) 95 engine interface 96 system bus 97 working memory 98 CPU (control unit) 99 ROM 100 density conversion unit 101 UCR / black generation unit 102 color correction unit 103 gamma correction unit 104 gradation processing unit 105 specific resolution Conversion unit 106 Feature calculation unit 107 Buffer 110 Low-resolution image memory 111 Feature color counter 112 Template selection unit 113 Template storage memory 115 Main / sub-pixel counter 116 Interrupt signal line 120_C0 Feature color detector 120_C1 Feature color detector 120_C2 Feature color detection Unit 121 comparator 122 AND gate 123 counter 124 count buffer 125 set of blocks 126 block 127 secondary determination unit 128 input layer 129 middle layer 130 output layer 131 Comparison means 140 Clock signal line 141 Line synchronization signal line 142 Image data line 143 Print control signal line 144C, 144M, 144Y, 144K Print color designation signal line 145 Serial communication line

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/387 G03G 21/00 550 5C077 9A001 F term (Reference) 2C005 HA04 LB46 LB60 2H027 DB00 EH06 FA28 FB12 FD08 2H030 AD07 AD12 AD16 2H034 FA01 5C076 AA22 AA40 BB06 BB25 CB05 5C077 LL14 MP08 PP20 PP32 PP42 PP48 PP55 PP61 PP65 PP68 PQ08 PQ15 PQ17 PQ18 PQ19 PQ20 PQ22 RR18 RR19 TT06 9A001 HH31 JJ35 KK42

Claims (8)

[Claims] An image reading device for scanning a document under the control of the reading controller and outputting color image data; a copying controller and an image forming unit; An image forming apparatus that inputs color image data from the image reading device to form a color image on the image forming unit based on control of the image reading device. A storage unit that stores the color image data input from the device, a specific image detection unit that detects a specific image included in the input color image data, and a storage unit that stores, based on a detection result of the specific image detection unit, A control unit for controlling whether or not the image forming unit forms the stored color image data. Image copying system. 2. The control section, when one or more color image data is stored in the storage section, outputs an instruction signal for instructing the image forming section to start image formation, and outputs the identification signal. 2. The image copying system according to claim 1, wherein when the image detection unit determines that the specific image is present in the temporary determination, the instruction signal is canceled and a hold signal is output. 3. The control unit according to claim 2, wherein when the specific image detecting unit determines that there is no specific image in the final determination, the control unit cancels the hold signal and outputs an instruction signal again. Image copying system. 4. The apparatus according to claim 2, wherein the specific image detecting section outputs a result of the provisional judgment before the image forming section starts visualization processing based on color image data. Image copying system. 5. An image reading apparatus, comprising: a reading controller for scanning a document under the control of the reading controller to output color image data; a copying controller; and an image forming unit; An image forming apparatus for inputting color image data from the image reading device under control of a controller for forming a color image in the image forming section, wherein the copy controller includes the image reading device. A storage unit for storing at least one image of the color image data input from the CPU, and a specific image detection for detecting a specific image included in the input color image data by a plurality of steps including at least two steps of provisional determination and final determination And a color image data stored in the storage unit based on a detection result of the specific image detection unit. And a controller for processing the data to form a color image based on the processed color image data in the image forming unit. 6. The control unit performs a predetermined processing on the color image data stored in the storage unit when the specific image detection unit determines in the final determination that there is a specific image. The image copying system according to claim 5, wherein 7. The control unit performs a scaling process on the color image data stored in the storage unit when the specific image detection unit determines in the final determination that there is a specific image. The image copying system according to claim 6. 8. An image reading apparatus, comprising: a reading controller for scanning a document under the control of the reading controller to output color image data; a copying controller; and an image forming unit; An image forming apparatus for inputting color image data from the image reading device under control of a controller for forming a color image in the image forming unit, wherein the reading controller reads the read image. A copying machine, wherein the copying controller has a storage unit that stores the color image data input from the image reading device, and a detection unit that detects the specific image included in the color image data. Based on the result, whether to cause the image forming unit to form the color image data stored in the storage unit And a control unit for controlling whether the image is copied or not.