JPH11341252A - Image formation device, image formation method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the directions of characters on each recording paper be the same by controlling the direction based on the result of discriminating the direction of the characters by a character discrimination means at the time of recording the image data of one screen separately on the plural sheets of the recording paper. SOLUTION: Input image data are separated for the respective attributes of a character part, a graphic part and a chart part, etc., in an area separation part 403, rectangular area information is prepared, a character area is extracted from it and the character direction is discriminated by using several blocks. For direction discrimination, character recognition is performed by changing the direction of reading from a CPU/memory part 401 to 0 deg., 90 deg., 180 deg. and 270 deg., comparison with a character recognition dictionary stored beforehand is performed and the image data are rotated in the direction of highest accuracy. Then, the correction processing of the difference of area separation information accompanying rotation is performed to rotated images and the processing results of the character recognition by a character recognition processing system and the separation information are transmitted through an I/F part 405 to a computer 406, also transmitted to a CPU inside a controller part and used for the image processing of enlarged consecutive photographing copying or the like and control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for recording an image on a recording sheet in accordance with image data, and more particularly to a mode for recording an image of one screen on a plurality of recording sheets.

[0002]

2. Description of the Related Art Conventionally, in such an image forming apparatus, a so-called reduced layout function for reducing a plurality of originals on a single sheet of recording paper and conversely, recording one original on a plurality of sheets. Some have an enlarged continuous shooting function for recording on paper.

[0003]

However, a document that has been reduced in layout often has a different layout depending on the person who created the document. Therefore, when the original is enlarged and continuously photographed, the recording paper on which the enlarged continuous photographing is performed may not be output in a desired direction.

[0004] Furthermore, if staple processing or bookbinding processing is selected as post-processing, an unaligned one will be created. To start over, remove the staple needle or remove the glue at the time of bookbinding. It is time-consuming, such as having to adjust the direction and perform post-processing again.

The present invention has been made under such circumstances. When an image of one screen is divided and recorded on a plurality of recording papers by image data, the direction of characters on each recording paper is changed. It is an object of the present invention to provide an image forming apparatus, an image forming method, and a storage medium that can be the same.

[0006]

In order to achieve the above-mentioned object, according to the present invention, an image forming apparatus is configured as follows (1) to (5), and an image forming method is configured as follows (6). Then, the storage medium is configured as in the following (7).

(1) An image forming apparatus for forming an image on recording paper using image data, a character direction determining means for determining the direction of a character in the image based on the image data, and one screen based on the image data Control means for controlling the direction of characters on each recording paper to be the same based on the result of the determination by the character direction determining means when the image is recorded on a plurality of recording papers. Forming equipment.

(2) In the image forming apparatus described in (1), the character direction determining means recognizes characters included in a character area in an image from a plurality of directions, and has the highest character recognition accuracy. An image forming apparatus that determines a direction as a direction of a character.

(3) In the image forming apparatus as described in (2), the character direction determining means performs character recognition on a plurality of characters in the same character area and determines based on the result. .

(4) In the image forming apparatus described in (2), the character direction determining means performs character recognition on characters included in a plurality of character areas and performs determination based on the result. apparatus.

(5) The image forming apparatus according to any one of (1) to (4), wherein the image forming apparatus is a copying machine.

(6) An image forming method in an image forming apparatus for forming an image on recording paper by using image data,
A first step of determining a direction of a character in an image based on the image data; and a first step of dividing an image of one screen on a plurality of recording sheets by using the image data. A second step of controlling the directions of the characters on each recording paper to be the same based on the determined result.

(7) A storage medium storing a program for realizing the image forming method according to (6).

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to examples of a digital copying machine. The present invention is not limited to a copying machine, and can be implemented by an appropriate image forming apparatus such as a printer or a facsimile that outputs a so-called hard copy using image data. The present invention is not limited to the form of the image forming apparatus, but may be a form of an image forming method and a CD-ROM storing a program for realizing the image forming method.
The present invention can be similarly implemented in the form of a storage medium such as a ROM.

[0015]

FIG. 1 is a sectional view showing the structure of a "digital copying machine" according to an embodiment. In FIG. 1, reference numeral 101 denotes a document table glass on which documents fed from the automatic document feeder 142 are sequentially placed at predetermined positions. Reference numeral 102 denotes a document illumination lamp composed of, for example, a halogen lamp, which exposes a document placed on the document table glass 101. 103,
Scanning mirrors 104 and 105 are housed in an optical scanning unit (not shown), and guide the reflected light from the document to the CCD unit 106 while reciprocating. CCD unit 1
Reference numeral 06 includes an imaging lens 107 that forms an image of reflected light from a document on the CCD, an image sensor 108 including the CCD, a CCD driver 109 that drives the image sensor 108, and the like. The image signal output from the image sensor 108 is
For example, after being converted into 8-bit digital data, it is input to the controller unit 139.

Reference numeral 110 denotes a photosensitive drum, which is discharged by a pre-exposure lamp 112 in preparation for image formation. A primary charger 113 charges the photosensitive drum 110 uniformly. Reference numeral 117 denotes an exposure unit, which is composed of a semiconductor laser or the like, and which performs image processing and controls the entire apparatus.
The photosensitive drum 1 based on the image data processed in 39
10 is exposed to form an electrostatic latent image. Reference numeral 118 denotes a developing device which stores a black developer (toner). 11
A pre-transfer charger 9 applies a high voltage before transferring the toner image developed on the photosensitive drum 110 to a sheet. 12
Reference numerals 0, 122, and 124 denote paper feeding units. Transfer paper (recording paper) is fed into the apparatus by driving the paper feeding rollers 121, 123, and 125, and temporarily stops at the position where the registration rollers 126 are provided. The timing for starting writing with the image formed on the photosensitive drum 110 is set, and the sheet is fed again. 127
Denotes a transfer charger, which transfers the toner image developed on the photosensitive drum 110 to a fed transfer sheet. Reference numeral 128 denotes a separation charger, which separates the transfer paper having undergone the transfer operation from the photosensitive drum 110. The photosensitive drum 110 without being transferred
The remaining toner is collected by the cleaner 111. Reference numeral 129 denotes a transport belt which transports the transfer paper, on which the transfer process has been completed, to the fixing device 130, and fixes the transfer paper by heat.
Reference numeral 131 denotes a flapper, which controls the conveyance path of the transfer sheet having undergone the fixing process in one of the directions in which the staple sorter 132 or the intermediate tray 137 is arranged. The paper discharged to the staple sorter 132 is sorted into each bin, and the staple unit 141 staples according to an instruction from the controller unit 139. When a bookbinding device (glue binder) 145 is mounted in place of the staple sorter 132, a spine and a bundle of paper with glue are glued by the binder unit 143 according to an instruction from the controller unit 139, and the stacker is stacked. In 144, the bundle of sheets after bookbinding is stored.
Reference numerals 133 to 136 denote feeding rollers, which invert (multiply) or non-invert (double-sided) the transfer sheet once subjected to the fixing process to the intermediate tray 137 and feed it. Reference numeral 138 denotes a re-feed roller, which conveys the transfer sheet placed on the intermediate tray 137 again to the position where the registration roller 126 is provided.

The controller section 139 includes a microcomputer, an image processing section, and the like, which will be described later, and performs the above-described copying operation in accordance with an instruction from the operation panel 140.

FIG. 2 is a block diagram showing the configuration of the controller unit 139. In FIG. 2, reference numeral 201 denotes a CPU for controlling the entire apparatus of the embodiment, and a read-only memory 203 storing a control procedure (control program) of the apparatus main body.
(ROM) to sequentially read and execute programs.
The address bus and the data bus of the CPU 201 are connected to each load via a bus driver circuit and an address decoder circuit 202. Reference numeral 204 denotes a random access memory (RAM) which is a main storage device used as storage for input data, a work storage area, and the like. 205
Reference numeral denotes an I / O interface. An operation panel 140 displays an operation state of the apparatus by using a liquid crystal or an LED, and motors 207 for driving a paper supply system, a conveyance system, and an optical system. Clutches 208, solenoids 20
9, and is connected to each load of a device such as paper detection sensors 210 for detecting the paper being conveyed. Developing device 11
A toner remaining sensor 211 for detecting the amount of toner in the developing device is provided at 8, and an output signal thereof is input to the I / O port 205. 215 is a high-pressure unit, and C
According to the instruction of the PU 201, the primary charger 113,
Developing device 118, pre-transfer charger 119, transfer charger 12
7. Output high voltage to the separation charger 128.

Reference numeral 206 denotes an image processing unit which receives an image signal output from the CCD unit 106, performs image processing described later, and performs laser processing on the laser unit 1 in accordance with image data.
And 17 control signals. The laser beam output from the laser unit 117 irradiates and exposes the photosensitive drum 110, and the light emission state is detected by a beam detection sensor 213 which is a light receiving sensor in a non-image area, and the output signal is output to an I / O port. 205.

FIG. 3 is a block diagram of the image processing section 206 in the controller section 139. In FIG. 3, the image signal converted into the electric signal by the image sensor 108 is first corrected for variations between pixels by a shading circuit 301, and then, in a scaling circuit 302, a data thinning process is performed at the time of reduction copying. During the enlargement copy, data interpolation is performed. Next, in the edge enhancement circuit 303, second differentiation is performed in a window of, for example, 5 × 5 (pixels) to enhance the edges of the image. Since this image data is luminance data, the γ conversion circuit 304 performs data conversion by table search in order to convert the image data into density data to be output to a printer. The image data converted into the density data is input to the binarization processing unit 305. Here, multi-value data is converted into binary data by, for example, the ED method. The binary-converted image data is input to the combining circuit 307. In the synthesizing circuit 307, the input image data and, for example, a DRAM
The image data in the image memory 310 constituted by the above is selectively output or ORed and output. The read / write control for the image memory 310 is performed by the memory control unit 309. These image data are input to a PWM circuit 308 for conversion into a signal of the laser emission intensity, and a pulse width according to the image density is output to the laser unit. An image output from the shading circuit 301 is input to a character direction determining unit 306, and performs a character recognition process and a character direction determination process described later.

Next, the character direction determining operation will be described with reference to FIGS. FIG. 4 is a block diagram of the inside of the character direction determination unit 306.

The image data output from the shading circuit 301 is input to the CPU / memory unit 401 to temporarily store the image data and perform various controls. The CPU 201 in the controller unit 139 is, for example, connected to a bus by a dual port RAM (not shown), and transmits and receives data. Of course, serial communication may be used.

The character recognition / direction discrimination unit 402 focuses on the fact that the most accurate representation of the direction of a document is a character, and identifies several types of character areas in the document as 0 °, 90 °, and 180 °.
The character recognition is performed from the directions of ° and 270 °, and the direction with the highest accuracy among the character recognition accuracy (the degree of confidence of the character recognition: the distance to the characteristic distribution of the character) in each direction is defined as the character direction.

As a pre-process for performing character recognition / direction discrimination processing by the character recognition / direction discrimination unit 402, a region separation unit 403 converts a character portion, a graphic portion, a natural image portion, a table portion, and the like from a document image data into a rectangle. This is a block for performing processing for adding an attribute (such as a character portion) of each area to each of the areas.

The storage device 404 is composed of, for example, a hard disk or a magneto-optical disk, and is used to store various processing results (image data, area separation results, character recognition results, etc.). The I / F unit 405 is a SCSI
And RS232C, etc., and are provided for transmitting data to the outside. Computer 406
Information is obtained via the I / F unit 405 or data is obtained from a movable storage device such as a magneto-optical disk and used.

Next, the outline of the character direction automatic discrimination / correction and character recognition processing in this embodiment will be described with reference to the flowchart of FIG.

The input image data (multi-valued image) is first separated by the region separating unit 403 into rectangular regions for each attribute such as a character portion, a graphic portion, a natural image portion, and a table portion (steps S1 and S2). ). Here, actually, area information surrounded by a rectangle is created.

Next, rectangle information of the character area is extracted from each attribute (step S3). Here, the character area includes a text part, a title part, characters in a table, a caption part of a figure, and the like. For example, in the case of the documents shown in FIGS.
The rectangular information of the character area as shown in FIGS. 6B and 6D is extracted. Then, the character direction is determined by using several blocks among them (step S4). As a result, if the character direction is the forward direction, the character recognition process is continuously performed on the character block in the image (step S).
7). On the other hand, if the character direction is incorrect, the image data is rotated in the correct direction (step S5). And
Region separation is performed on the rotated image, and correction processing of the region separation information is performed (step S6). This is to correct the difference in the area separation information due to the image rotation. One method is to perform the area separation processing again on all the rotated image data. There is a way to apply. Since the area separation processing generally assumes that the image is in the forward direction, the results of the area separation processing performed in the initial stage and the area separation processing performed on the rotated image data often differ. Therefore, it is desirable that the former method be used.

Next, proceeding to step S7, the character area block in the rotated image data is recognized by the character recognition processing system. As a result, the segmentation information and the character recognition information are finally obtained in both the case without the rotation and the case with the rotation (step S8).

The processing result is transmitted to the computer 406 via the I / F unit 405, and is used by filing application software on the computer 406. The image is transmitted to the CPU 201 in the controller unit 139 for each image.

Next, a method of character direction discrimination using character recognition processing will be described.

[Region Separation Processing] The black pixels of the document image data are detected, and a rectangular frame of black pixel blocks is created by contour tracing or labeling. Next, the character area (title, body, caption, etc.), graphic area, natural image area, table area, etc. are determined based on the black pixel density in the rectangle, the presence or absence of adjacent rectangular blocks, the aspect ratio of the rectangle, and the like. Is determined. The rectangular area of the character area is determined based on the processing result.

[Character Recognition Processing] One method of character recognition processing is a feature vector extraction and comparison method. For example, as shown in FIG. 7A, it is assumed that a character area including the character "book" is determined. As a first step, a character cutout process is performed on this character area (see FIG. 7B). This is a process of cutting out a rectangle of one character, and is obtained by detecting the state of black pixel continuity. As a second step, one character is cut into m × n (for example, 64 × 64) pixel blocks (see FIG. 7C). Then, the distribution direction of the black pixels is extracted from among them using a 3 × 3 pixel window (direction vector information: see FIG. 7D).

FIG. 7D exemplifies a part of the direction vector information. The window of 3 × 3 pixels is shifted to obtain several tens of direction vector information. This vector information is a character feature. By comparing this feature vector with the contents of the character recognition dictionary stored in advance,
Characters are extracted in order from the character whose feature is closest to the feature vector. In this case, the first candidate, the second candidate,... The closeness of the feature to this feature vector is a numerical value of the closeness of the distance to the character, that is, the confidence (accuracy) of the character recognition.

[Character Direction Judgment Processing] The confidence level of the character recognition is obtained in this manner. The character direction discrimination processing based on the confidence degree is performed by using a sentence example of "Name of the present invention" shown in FIG. Will be explained.

FIG. 8A shows a sentence in the forward direction, and FIG.
The sentence is rotated 70 degrees. If you focus on "books" here,
When determining the character direction, as shown in FIG. 8C, 0 °, 90 °, 180 °
Let's try character recognition from four directions, ° and 270 °. For each rotation angle, it is sufficient to change how to read the character rectangular area, and it is not necessary to rotate the document.

FIG. 8 shows the result of character recognition at each rotation angle.
As shown in (c), they are different from each other. Note that FIG. 8C shows a provisional character recognition result and a degree of self-confidence for explanation, and this is not always the case.

In FIG. 8 (c), when character recognition is performed from the positive direction (0 °), “book” is correctly recognized, and the degree of confidence is as high as 0.90. When character recognition is performed from a direction rotated by 90 °, the character is erroneously recognized as “town”, and the confidence level is reduced to 0.40. The reason why the erroneous recognition occurs and the confidence level is reduced is that the character recognition is performed based on the feature vector when viewed from the rotating direction. Similarly, when character recognition is performed from a direction rotated by 180 ° or 270 °, erroneous recognition occurs and the degree of confidence is reduced. In addition,
As for the degree of confidence in each direction of character recognition, the difference becomes more noticeable as the characters become more complex.

The result shown in FIG. 8C indicates that the document (character) is highly likely to be oriented in the forward direction because the confidence is highest in the forward direction. In order to improve the accuracy of character direction discrimination, character recognition is performed for a plurality of characters in the same block from four directions in the same manner. Furthermore, if the character direction is determined only by one block, the character direction may be erroneously determined for a special character string.
Perform similar character recognition for multiple blocks.
Then, for each block, an average value of the degrees of confidence in the four directions of each character to be recognized in the block is calculated, and further,
The average value of the confidence values in the four directions in each block is calculated, and the direction with the highest average value is recognized as the character direction (document direction).

As described above, the character direction is determined based on the confidence of a plurality of characters in the same block, and further, the character direction is determined based on the confidence of a plurality of characters in the plurality of blocks without determining the character direction based on the confidence of only one character. The direction can be determined with high accuracy. However, needless to say, even if the character direction is determined based on the degree of confidence of only one character, or the character direction is determined based on the degree of confidence of a plurality of characters in the same block, the character direction can be determined with higher accuracy than before.

Next, when the result of the character direction determination is a direction other than the forward direction, the original image is rotated so that the character direction becomes the forward direction. This rotation is performed by the CPU / memory 40 shown in FIG.
1 can be easily performed by a known technique, and a description thereof will be omitted.

By the above processing, the original image data shown in FIG. 9A, the area separation data shown in FIG. 9B, and the character recognition information shown in FIG. 9C can be obtained. . These pieces of information are stored in the controller 139 as described above.
And is used for various image processing and various controls.

As shown in FIG. 9B, the format of the area separation data is "head" indicating that the data is area separation data.
r ”and the identifiers of the separated areas“ rect1 ”to“ re
ct4 ”..., and information of each area (block) distinguished by the identifier is a block number“ ord ”.
er ", block attributes (character part, figure part, etc.)" ar
t ", coordinate values" x1 "and" y "at the upper left of the block.
1, "width" of the block, "h" of the block, "direction" indicating vertical or horizontal writing, "selfID" which is the ID of the block, and "ID of the parent block including the block" upperI
D ", an attribute" upperArt "of the parent block, and a reserve area" reserve ".

As shown in FIG. 9C, the character recognition information "head" indicating that the character recognition information is character recognition information.
For example, character recognition information “OCR1” or the like relating to a single character such as “book” and “blk” corresponding to “rect1” or the like indicating a block including the character.
header ".

Each character recognition information such as “OCR1” is “type” indicating whether it is a character or a blank.
e ", the first to fifth candidate characters" character 1 "to" character 5 "according to the above-described degree of confidence in character recognition, the cutout positions" x1 "and" y1 "of the character, and the width" w "of the character. , The height of the character "h", and a spare area "reserve".

Next, a conventional enlarged continuous shooting will be described with reference to FIG.

As shown in FIG. 10A, for example, when two originals are correctly copied on one sheet, the upper character string and the lower character string of the paper are laid out in the same direction. I have. When this sheet is divided into two sheets as a document and copied, the output is made in the same direction as shown in the figure.
However, as shown in FIG. 10B, when a document in which the upper character string and the lower character string are laid out in different directions is divided into two and copied, the orientation is changed as shown in the figure. It is output as it is. In order to prevent this, the operator must set the mode of the enlarged continuous shooting by grasping the direction in advance. Even in this case, the layout in the case of FIG.
If the layout in the case of (b) is mixed, an output in the correct direction cannot be obtained.

Next, the operation of enlarged continuous shooting in this embodiment will be described with reference to the flowchart of FIG. 11 and the explanatory diagram of FIG.

First, in step S11, it is determined whether or not the enlarged continuous copy mode has been selected. If the mode is not the enlarged continuous copy mode, other copy processing operations are performed in step S16, and the process ends. If the enlarged continuous copy mode is selected in step S11, the process waits for a copy key in step S12. Step S when the copy key is turned on
The character recognition area is divided according to the enlarged continuous copy mode set in step S13. For example, if 1 to 4 mode, 4
In the 1to6 mode, the area is divided into six areas. Next, the orientation of the character is recognized by the character recognition process described with reference to FIGS. 7 and 8 for each area divided in step S14. Then, the character recognized in step S15 is copied and output in a correct direction. It should be noted that the enlarged continuous copying is a known technique, and a description thereof will be omitted.

By the above operation, as shown in FIG. 12, both the upper and lower characters of the original in the same direction and the upper and lower characters of the original in different directions are output in the correct character direction. .

Although the present embodiment is an example of a digital copying machine, the present invention can be similarly applied to an appropriate image forming apparatus such as a printer or a facsimile which outputs a so-called hard copy based on image data.

[0052]

As described above, according to the present invention,
When image data of one screen is divided and recorded on a plurality of recording papers by the image data, the direction of characters on each recording paper can be made the same, and post-processing such as stapling and bookbinding can be easily performed. It can be carried out.

[Brief description of the drawings]

FIG. 1 is a diagram showing the overall configuration of an embodiment.

FIG. 2 is a diagram showing a configuration of a controller unit.

FIG. 3 is a diagram illustrating a configuration of an image processing unit.

FIG. 4 is a block diagram showing a configuration of a character direction determination unit.

FIG. 5 is a flowchart showing character direction discrimination and character recognition processing.

FIG. 6 is an explanatory diagram of character area separation.

FIG. 7 is an explanatory diagram of character recognition (part 1).

FIG. 8 is an explanatory diagram of character recognition (part 2).

FIG. 9 is an explanatory diagram of character recognition (part 3).

FIG. 10 is an explanatory diagram of conventional enlarged continuous shooting.

FIG. 11 is a flowchart showing an enlarged continuous shooting process;

FIG. 12 is an explanatory diagram of enlarged continuous shooting in the embodiment.

[Explanation of symbols]

 306 Character direction discriminator

Claims (7)

[Claims] 1. An image forming apparatus for forming an image on recording paper using image data, comprising: a character direction determining unit configured to determine a direction of a character in the image based on the image data;
When a single screen image is divided and recorded on a plurality of recording papers by the image data, control is performed such that the direction of characters on each recording paper is the same based on the determination result of the character direction determination means. And an image forming apparatus. 2. The image forming apparatus according to claim 1, wherein
The image, wherein the character direction determining means recognizes characters included in a character area in the image from a plurality of directions, and determines the direction with the highest character recognition accuracy as the direction of the character. Forming equipment. 3. The image forming apparatus according to claim 2, wherein
The image forming apparatus is characterized in that the character direction determining means performs character recognition on a plurality of characters in the same character area and determines based on the result. 4. The image forming apparatus according to claim 2, wherein
The image forming apparatus according to claim 1, wherein the character direction determining means performs character recognition on characters included in a plurality of character areas and performs determination based on the result. 5. An image forming apparatus according to claim 1, wherein said image forming apparatus is a copying machine. 6. An image forming method in an image forming apparatus for forming an image on recording paper using image data, comprising: a first step of determining a direction of a character in the image based on the image data; When the image of one screen is divided into a plurality of recording papers and recorded on the basis of the discrimination result determined in the first step, control is performed such that the direction of the characters on each recording paper is the same. And an image forming method. 7. A storage medium storing a program for realizing the image forming method according to claim 6.