JP2000029198A - Color proof device, image processor and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and accurately grasp the difference of pixel information between two images in color proof. SOLUTION: The respective partial enlarged images of the first proof (old base), the second proof (new base) and a compared result image (difference image) are displayed in an enlarged image display window LW on the screen of a display. Cursors CS1, CS2 and CSM are displayed, on the enlarged images. By designating the position of optional one among the cursors CS1, CS2 and CSM, other cursors follow the optional one on the respective enlarged images, and also the color component values of the pixels of the images are displayed in parallel on a pixel information display window as numerical values. The alignment of the cursors is not required on the first proof, the second proof and the compared result image, respectively, and the color component values of the corresponding pixels are rapidly and accurately compared.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in plate inspection technology for comparing first and second images obtained in a plate making process and outputting the comparison result as a visually acceptable plate inspection result image. The present invention relates to a technology generally extended to an image comparison device.

[0002]

BACKGROUND OF THE INVENTION In the process of making a printed material, it is checked whether a plate obtained by editing image parts such as characters, photographs, and line drawings conforms to the contents of the plate making instruction, and does not conform to the instruction contents. Sometimes various corrections need to be made. Then, such inspection and correction are repeatedly performed in a number of stages, and after the first school, re-school, three schools, etc., a finally completed version is obtained.

[0003] In such a plate inspection apparatus for digitally performing a comparative inspection of each plate, a plate inspection result image of an old plate and a new plate to be compared is displayed on a display and printed on a medium such as paper or film. It is configured to be printable. In such a plate inspection result image, the matching part and the different part of the old version and the new version are visually distinguished and expressed, whereby the operator specifies the corrected part and the correction is properly performed. You can check if.

[0004]

2. Description of the Related Art Although such a plate inspection apparatus is configured to automatically point out a difference between two images, a slight difference in color tone or the like is not considered. In some cases, it is difficult to confirm only by visual recognition of the operator.

Therefore, a function (so-called spoid function) of taking in pixel information (color component value) of a pixel designated by an operator from the plate inspection result image displayed on the display and displaying the content is added. However, although a plate inspection apparatus often compares pixel information of pixels corresponding to each other in a plurality of images to be compared, a conventional plate inspection apparatus captures pixel information of one pixel. Could only be displayed with

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned problems in the prior art, and makes it possible to easily and accurately grasp the difference in pixel information between two images to be compared, thereby improving the efficiency of plate inspection work. The first purpose is to make the

A second object of the present invention is to extend the concept of improving the plate inspection apparatus to a general image processing apparatus.

[0008]

In order to achieve the above-mentioned object, the first aspect of the present invention relates to a first and a second method which are obtained in a plate making process.
A plate inspection device for comparing and inspecting the images of (a), wherein (a) a display for displaying, as a first and a second display image, regions corresponding to each other on the first and second images on a predetermined screen; Means, (b) operating means for specifying a position of a cursor displayed on the screen, and (c) a specified position of a first cursor on one of the first and second display images. Cursor following means for following a second cursor to a corresponding position on the other display image, (d) first pixel information at the designated position of the one display image, and the other display image Pixel information display control means for displaying the second pixel information at the corresponding position on the display means.

According to a second aspect of the present invention, in the device of the first aspect, the one of the display images is the first display image or the second image, and the other display image corresponds to the first cursor. The above is characterized in that the second cursor follows.

According to a third aspect of the present invention, in the device of the first or second aspect, the first and second display images corresponding to the first and second display images among the plate inspection result images of the first and second images are provided. Is also displayed on the display means as a third display image, the cursor following means includes: i) a position of the first cursor on the one display image; ii) a position of the first cursor on the other display image. Iii) the position of the third cursor on the third display image, and iii) the position of the third cursor on the third display image. Means to follow.

According to a fourth aspect of the present invention, in the apparatus of any one of the first to third aspects, the display means further displays difference information between the first and second pixel information. And

According to a fifth aspect of the present invention, in the apparatus according to any one of the first to fourth aspects, the first and second images are color images, and the first and second pixel information is a color image. It is characterized by including information corresponding to the size of each color component in a pixel.

According to a sixth aspect of the present invention, in the apparatus according to any one of the first to fifth aspects, at least one of the first and second images is a digitally edited image in a digital state. This is obtained by pixel development.

According to a seventh aspect of the present invention, in the apparatus according to any one of the first to fifth aspects, at least one of the first and second images is obtained by photoelectrically converting an image of a plate on which exposure recording or printing recording is performed. Is obtained by reading the data.

The invention according to claim 8 is applied to an image comparison apparatus for comparing first and second images, and (a) regions corresponding to each other are defined for the first and second images. Display means for displaying as a display image; (b) operation means for operating and moving a first cursor on the screen of the display means; and (c) display means for displaying one of the first and second display images. Means for causing the second cursor to follow the corresponding position on the other display image in accordance with the position specified by the first cursor, (d)
Pixel information display control means for causing the display means to display first pixel information at the designated position of the one display image and second pixel information at the corresponding position of the other display image, Prepare.

A ninth aspect of the present invention is a storage medium for realizing the device of the ninth aspect using a computer,
(A) display means for displaying, as first and second display images, areas corresponding to each other with respect to the first and second images; and (b) operating a first cursor on a screen of the display means. Operating means for moving; (c) a second cursor at a corresponding position on the other display image according to a position designated by the first cursor on one of the first and second display images; And (d) displaying, on the display means, first pixel information at the designated position of the one display image and second pixel information at the corresponding position of the other display image. And a computer-readable recording medium storing a program for causing the apparatus to function as a device including a pixel information display control unit.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

[0018]

FIG. 1 is a schematic block diagram of a plate making system 1 including a plate inspection apparatus 100 according to an embodiment of the present invention. In the plate making system 1, data of various image parts (characters, line drawings, photographs, etc.) is input from the image part input device 2. The image parts input unit 2 includes, for example, an input scanner, a character input unit, and a line drawing. It is composed of a creation unit and the like.

The data of the image parts input from the image part input device 2 is given to the image editing / conversion device 3 online or offline, and after being laid out on each page in the page description language according to the plate making instruction, The image data is developed into image data in pixel units (RIP development), and further converted into a halftone image in an image output unit 4 including an output scanner and recorded on a photosensitive material by exposure. Then, the photosensitive material on which the exposure recording has been performed is developed to obtain a printing original plate.

Once a portion requiring correction is found in the image of the created version (old version), the process returns to the image component input device 2 or the image editing / converting device 3 to re-input the old version image component or to delete the image data on the page. Make corrections to obtain a new version of the image data. The new version is compared with the old version by using the plate inspection apparatus 100 to check for corrections, and when leaks or new corrections are discovered, the version is repeatedly corrected. An original version (printed version) for printing plate production is obtained.

In the actual plate making process, plate correction is often repeated a plurality of times. In the following, attention will be paid to correction at an arbitrary stage, and a description will be given assuming that a version before the correction is an old version and a version after the correction is a new version. to continue. The old version is, for example, the first school, and the new version is, for example, a re-school.

The plate inspection apparatus 100 for performing a comparison inspection between the old version and the new version can take in images of these original versions in two types. First, color image data of the old edition and the new edition which are RIP-decompressed by the image editing / conversion device 3 are taken in the form of digital data and compared. The capture of the digital data may be performed online via a network, or may be performed offline using an information storage medium such as a magnetic disk or a magneto-optical disk. In the example of FIG. 1, the plate inspection apparatus 100 is network-connected to the image editing / conversion apparatus 3 and the like so that data can be taken online.

Another method of capturing the image data of the original is to convert the visible image of each YMCK original that has been developed after exposure recording or the proof image recorded in color printing on proof paper by photoelectric conversion. This is a method of reading information. The plate inspection apparatus 100 shown in FIG. 1 includes an image reader 110 in order to realize this method. In the case of a color image, the original plate usually consists of four plates of Y, M, C and K,
When the original is read by the image reader 110, these 4
The image of the plate is read, and one set of color plate image data of each color component is used as one original plate image data. Note that it is also possible to read an image on a printing plate instead of the original plate.

In addition to the above two methods, one of the two images to be compared is used as it is as the RIP-developed digital image data, and the other is obtained by photoelectrically reading an image on a print medium. Things can also be used.

[0025]

[Configuration of Plate Inspection Apparatus] The plate inspection apparatus 100 includes an operation control unit 130 that controls various inputs and outputs, in addition to a comparison operation of image data. The arithmetic control unit 130 can be constituted by a main body of a computer, and includes a CPU 131 and a memory 132. The media drive 120
In addition to inputting image data offline, CD-
It is also used when the arithmetic control program of the plate inspection apparatus 100 is read in advance from the information storage medium MA provided in the form of a ROM. This operation control program is executed by the operation control unit 1
30. A display control program on the color display 140 and an output control program to the color printer 150 and the plotter 160 as described later are also included in the arithmetic control program provided in the form of the storage medium MA.

The image disk 170 is constituted by a magnetic disk such as a large-capacity hard disk, and stores image data before and after plate inspection, and stores a plate inspection result image obtained as a result of plate inspection.

A color display 140 is connected to the arithmetic control unit 130. An operation input and menu selection according to the display on the display 140 can be performed by a keyboard 181 and a mouse 182 included in the operation input unit 180.
This can be done using Color display 140
Is displayed in every scene of operation input, but it is particularly important to display the inspection result image of the old version and the new version and make the operator visually recognize the contents, in relation to the essential purpose of the inspection. It is.

A color printer 150 and a plotter (monochrome plotter) 160 are also used to output the inspection result images of the old version and the new version. As the color printer 150, for example, an ink jet printer can be used. The output medium of the color printer 150 and the plotter 160 is a fixed image recording medium (image recording sheet) such as plain paper, translucent paper, or transparent film.

[0029]

[Inspection Operation] <Overview of Inspection Target Image and Inspection Result Image> FIG. 2 is a diagram showing an example of an old plate image P1 and a new plate image P2 which are compared and inspected by the plate inspection apparatus 100. This figure 2
In the example of the above, in the process of correcting the old version image P1 to the new version image P2, the image components are corrected in the regions CR1 to CR3 corresponding to these images P1 and P2. The plate inspection device 100 detects the correction regions CR1 to CR3 by comparing and inspecting these images P1 and P2. Then, the plate inspection apparatus 100 generates an output image in which a matching portion (non-correction region) of the images P1 and P2 and a different portion (correction regions CR1 to CR3) are visually distinguishable, and the generated output image is displayed. The image can be displayed on the screen 140 and visually output using the color printer 150 or the plotter 160.

When an output image obtained by such a comparison inspection is generally called a “plate inspection result image”, in this embodiment, the following three types of plate inspection result images are generated (the details of each are described later). .

A framed image CM1 (see FIG. 8 (a)): The location of the different part between the images P1 and P2 of both versions is indicated by a rectangular frame line K1.
These are images indicated only by K3. Since the framed image CM1 does not include an image content such as a photograph, the plotter 160 is mainly used when outputting this as a hard copy.

The area identification image CM2 (see FIGS. 9 and 10)
This is the difference between the images P1 and P2 of the two versions.
3 is represented by one of the images P1 and P2, and the visual density of the matching image content is reduced for the matching portion as shown in FIG. 9 or is set to a white background as shown in FIG. Thus, the image of the different part and the area of the coincident part can be identified. When outputting the area identification image CM2 as a hard copy, the color printer 150 is used. In addition, in the device 100 of this embodiment, the images P1,
It is also possible to select to represent the inside of the different part of P2 by the difference image of the images P1 and P2.

Difference frame image CMB (see the window in FIG. 8B): This is an image in which the whole ground color of framed image CM1 is relatively dark. The substantial image information is the same as that of the framed image CM1, but the image with the ground color is distinguished by reading it as “difference frame image” here. The color used as the ground color in the difference frame image CMB is a transparent color so that the frame lines K1 to K3 can be visually recognized. In FIG. 5B, this ground color portion is shown with diagonal lines, and this difference frame image CMB is referred to as an “erasing operation” described later.
Used in

<Generation of Plate Inspection Result Image> FIG.
FIG. 3 is an explanatory diagram showing the plate inspection operation in FIG. 3. In FIG. 3, a flowchart mainly executed by software in the arithmetic control unit 130 in FIG. 1 and a block diagram showing a data use relationship are expressed in combination. I have.

First, the digital image data of the old-version image P1 and the new-version image P2, which are obtained as digital data with the RIP expanded or obtained by photoelectrically reading the visible image of the plate, are temporarily stored in the image disk 170. Is done. This initial state of the image disk 170 is shown in FIG. 3 with reference numeral 170a.

The digital image data of the old version image P1 and the new version image P2 are read from the image disk 170 (170a) (step S1), and respective parts of these images are compared with each other (step S2). In this comparison, as shown in FIG. 4, the images P1 and P2 are each divided into a matrix of small rectangular blocks {Bij}, and for each block Bij, the image of the old version image P1 and the corresponding image of the new version image P2 are divided. Compare with image.

Here, when the old version image P1 and the new version image P2 are color images, the comparison is performed for each YMCK color component. If the old image P1 and the new image P2 are obtained by photoelectrically reading a plate, an error occurs in the spatial positional relationship between the old image P1 and the new image P2. A data shift is performed such that the relative position between the old image P1 and the new image P2 is sequentially shifted by a small amount for each block Bij, and the mutual matching between the images is determined based on the positional relationship having the highest degree of correlation between the images. . For this portion, the technique disclosed in Japanese Patent Application Laid-Open No. 9-211836 disclosed by the applicant of the present invention can be used.

In such an image comparison, if the difference between the image levels of the old version image P1 and the new version image P2 in the block Bij for one or more color components is equal to or larger than a predetermined threshold, the block is determined to be a “mismatch block”. On the other hand, if the difference between the image levels in the block Bij for all the color components is equal to or smaller than a predetermined threshold, the block is determined to be a “matching block” (step S
3). As for the difference between the image levels in each block Bij, for example, a method of projecting the image level distribution in the block Bij onto a predetermined spatial axis and comparing the projected waveforms with each other can be adopted. And block B
A method of comparing the average values of the image levels in ij may be employed.

<Identification of Different Parts and Setting of Frame Lines> FIG. 5 conceptually shows the result of the above-described matching judgment for each block Bij. Distributed throughout the surface. Here, since the new version image P2 is obtained by partial modification of the old version image P1, the unmatched blocks of those images are not randomly distributed, but the unmatched blocks are present in one or more places. . For example, in the example of FIG. 3, a set of mismatched blocks exists in the correction areas CR1 to CR3.

Therefore, as shown in FIG. 5, when a rectangular area R of the minimum size including a range in which unmatched blocks are continuous is set as a different part, in the case of the example of FIG. 2, FIG. The rectangular areas R1 to R3 shown in a) are specified corresponding to the correction points CR1 to CR3 in FIG. 2 (step S4 in FIG. 3).

Further, the different part R thus specified
For 1 to R3, frame lines K1 to K3 (FIG. 8A) are generated as outer frame images surrounding the outer periphery of each rectangular area (step S5 in FIG. 3). The color of the frame lines K1 to K3 to be image-expressed can be designated in advance by a selection operation of an operator (step S5a).

When the frame lines of the rectangular areas R1 to R3 are set in this manner, only such frame lines are displayed in FIG.
The framed image CM1 of (a) is generated (step S6).

Further, the outside of the frame of the framed image CM1 is painted with a predetermined dark color, and the inside of the frame is painted with a predetermined light color, and a difference frame image CMB shown in FIG. 6 described later is also generated (step S6a). . These images CM1 and CMB are
It is stored on the image disk 170. In FIG. 3, the image disk 17 after the various inspection result images are stored as described above.
A state of 0 is shown with reference numeral 170b. Note that the difference frame image CMB may not be generated at this stage but may be generated after receiving an instruction to generate it from the operator.

FIG. 6 is a view showing a display example of the screen SC of the display 140, and FIG. 7 is an enlarged view of the dialog DLG of FIG. In the screen SC of FIG. 6, the old image P1 and the new image P2 are displayed in a window in a reduced state by thinning out the pixels, and among the three types of plate inspection result images obtained by the comparison inspection, the difference is shown. Frame image CM
B and a region identification image CM2 generated as described later are displayed in a window in parallel. The dialog portion DLG includes button displays for selecting various conditions as shown in FIG. 7, and among these, in the “framed color” selection section, the color of the frame of the frame lines K1 to K3 is changed. It is possible to select and specify from a plurality of colors.
a. In the example of FIG. 7, "red" is designated as the color of the frame line. The reason that the color of the frame line can be selected in this manner is that the region identification image C is used as shown in FIG.
This is because when a frame line is synthesized and displayed in M2, a color that stands out in relation to the color of the surrounding image can be selected as the color of the frame line.

<Generation of Region Identification Image and White Mask> The operation of selecting the “increased portion” and “decreased portion” in the dialog of FIG. 7 is performed in the next step S11a of FIG.
It is used when the operator selects and inputs which image content is to be displayed in the rectangular area defining 1 to R3. The meanings of the options are as follows.

In FIG. 7, "old platform" means "old version image P1", and "new platform" means "new version image P2". When "old unit" is selected for one of "increased unit" or "decreased unit", "old unit" is automatically selected for the other. Similarly, "increased unit" or "decreased unit" is selected. When "new stand" is selected for one of "", "new stand" is automatically selected for the other. Therefore, the choice between "old stand" and "new stand"
Either both the “increased part” and the “decreased part” are set to “old”, or both the “increased” and “decreased” are set to “new”.

1. For “increase” and “decrease”,
When red or green is selected: In this case, the difference R1
In each of R1 to R3, an image portion that exists only in the new image P2 but not in the old image P1 and an image portion that exists in the old image P1 but not in the new image P2 are displayed in selected colors. Therefore, the deleted image portion and the added image portion are overlapped and displayed in the frame.

2. When "increased portion" = new unit and "decreased portion" = new unit are selected: different portions R1 to R1 of the new image P2.
A portion corresponding to the range of R3 is cut out, and frame lines K1 to K
Region identification image CR2 pasted within the range of 3 (FIG. 9)
Is generated as one of the inspection result images.

3. When “increased portion” = old stage and “decreased portion” = old stage are selected: different portions R1 to R1 of the old version image P1
A portion corresponding to the range of R3 is cut out, and frame lines K1 to K3 are cut out.
The region identification image CR2 pasted within the range of K3 is generated as one of the plate inspection result images. The region identification image CR2 in this case corresponds to a case where the inside of the different parts R1 to R3 in FIG. 9 is replaced with images of “E”, “「 ”, and“ W ”in FIG. 2B.

Returning to FIG. As described above, when there is a selection input operation (step S11) on which image to represent in the different parts R1 to R3 (expression method), the image in the different parts R1 to R3 is selected according to the selection. The contents are created (step S12).

That is, when “old table” is selected by a button operation on the dialog DLG using the mouse 182 or the like, the image data of the old version image P1 stored in the image disk 170 corresponds to the different parts R1 to R3. The contents of the image data are extracted, and are extracted from the area identification image CM2.
Are adopted as images to be displayed in different portions R1 to R3. On the other hand, when "new stand" is selected, the contents of the image data corresponding to the different parts R1 to R3 are extracted from the image data of the new version image P2 stored in the image disk 170, and the extracted contents are used as the difference between the area identification images CM2. This is adopted as an image to be displayed in the sections R1 to R3.

In other words, when “old” or “new” is selected, the image data of the area corresponding to the different parts R1 to R3 in the area identification image CM2 is replaced with the old version image in accordance with the selection. It will be represented by the content of one of P1 and the new version image P2.

When the “increased portion” and “decreased portion” are designated by the colors “red” and “green”, the images are expressed while the “increased portion” and “decreased portion” are expressed in the respective colors. The combined difference image or increase / decrease image is generated as an image of the different portions R1 to R3.

On the other hand, the area where the old version image P1 and the new version image P2 coincide (coincidence part EQ in FIG. 9) is an area other than the different parts R1 to R3 on the image plane. It can be specified by inverting the generated instruction signals of the different parts R1 to R3. Further, since the image content of the old version image P1 matches the image content of the new version image P2 in the matching section EQ, in the area identification image CM2, any one of the image data of the old version image P1 and the new version image P2 is used. The image content of the EQ may be created. Therefore, in this embodiment, the image data of the new version image P2 is fetched, and the image of the area corresponding to the matching part EQ is extracted from the fetched image data (step S13).

In step S13, the image in the area of the coincidence portion EQ is converted into a density that is visually lower than the density of the images of the different parts R1 to R3. This is to improve the visibility of the different portions R1 to R3 relatively. Since reducing the visual density corresponds to increasing the "white" component, this process can be called a "white mask". In terms of the relationship with the level of the image signal,
“Reducing the visual density” corresponds to lowering the image signal level in a subtractive color mixing system such as YMCK.
An additive color mixing system such as BGR corresponds to increasing the image signal level.

As shown in the dialog DLG in FIG. 7, the degree of masking by the white mask can be variously selected. When the white mask is selected on the “strong” side, the degree of reduction in visual density increases, and the matching portion EQ
Image is expressed thinly. Conversely, when the white mask is selected on the "weak" side, the degree of reduction in visual density is reduced, and the image of the matching portion EQ is expressed relatively densely. If an intermediate level is selected, the white mask becomes medium. In particular, when the white mask is set to the maximum (most “strong” side), the matching portion EQ
Is a completely white background.

The selection of the degree of the white mask in the dialogue DLG is shown as a third step S13a. In the generation of the image of the coincidence portion EQ in the step S13, the selection in this step S13a is considered. As described above, the image data of the coincidence portion EQ can be obtained at any density in the range from the relatively strong white mask to the weak white mask. However, when the white mask is selected to the maximum, the coincidence portion EQ becomes a completely white background.
Contains no substantial image content, and the image data in this area is data expressing “white” or “transparency”.

When the images of the different portions R1 to R3 and the coincidence portion EQ are obtained as described above, in the next step S14, the image of the different portions R1 to R, the image of the coincidence portion EQ, and the frame line K1 9 are spatially synthesized, and FIG.
Alternatively, an area identification image CM2 shown in FIG. 10 is generated. Then, the area identification image CM2 is stored on the image disk 170.

The area identification image C thus created
M2 is displayed on the screen SC of FIG. 6 together with the difference frame image CMB. However, when displaying the entirety in the window on the screen SC, the reduced image state is obtained by performing pixel thinning or the like. When it is desired to partially enlarge and display, the image is displayed with reference to the image data stored in the image disk 170.

In this way, the operator sets the matching portion EQ between the old image P1 and the new image P2 on the screen SC in FIG.
And the different portions R1 to R3 can be visually confirmed. The area identification image CM2 is effective for knowing the image content of the coincidence part EQ and the different parts R1 to R3, and the difference frame image CMB is effective for knowing the spatial distribution state of the existing positions of the different parts R1 to R3. is there.

In particular, in the different portions R1 to R3, as shown in FIG. 9, the internal image can be confirmed by the image content of only the new version image P2 (or the old version image P1). The displayed content is easier to recognize as compared with the case where the new version image P2 is displayed in a synthesized state. For this reason, the image contents of the different portions R1 to R3 can be confirmed accurately and quickly, and the plate inspection efficiency is improved.

The difference frame image CMB includes different portions R1 to R1.
When the operator sequentially checks the contents of R3, it can be used to indicate whether the different part has already been checked, and the details will be described later.

The framed image CM1 and the area identification image CM2 shown in FIGS. 8A and 9 can be displayed on the screen SC, or can be printed as a hard copy as described above. The color of the frame line selected in the dialog DLG in FIG.
The same content can be selected not only for display on the screen SC but also for printing to a hard copy for the image content to be output to R3.

Therefore, here, how to use these inspection result images when printing as a hard copy will be described. Of course, in the case of printing as a hard copy, a register mark (register mark) or the like for indicating a reference position on an image surface is also printed, but these marks are not shown in these figures.

In the framed image CM1 shown in FIG.
Only the frame lines K1 to K3 for.
Is plotted by This framed image CM1 is
By plotting in actual size on semi-transparent paper (so-called tracing paper-like paper) or transparent film, the image content of the different parts R1 to R3 can be superimposed on the old or new original or proof print, This is useful for confirming whether an image is an image.

FIG. 9 shows an area identification image CM2 to which a medium white mask is applied. In FIG. 9, the image portion represented by the dotted line is the coincidence portion EQ, but in an actual print, it is a portion printed by the color printer 150 at a low density. For the different parts R1 to R3, the corresponding areas of the new version image P2 are output.
Both the old version image P1 and the new version image P2 can be selected, but it is preferable to output the new version image P2. This is because the latest version at the present time is the new version image P2, and it is more appropriate to check the difference portions R1 to R3 in the new version image P2 in order to determine whether or not the correction is appropriate. This is the same when displaying on the screen SC.

By printing the area identification image CM2 in the same size as the printing plate, it is easy to confirm the image contents of the different portions R1 to R3 while visually confirming the state in the actual printing.

FIG. 10 shows a case where the white mask is designated as the maximum intensity, so that the different portions R1 to R3 have the new image P2.
This is an output example in which only (or the old version image P1) is displayed and the matching portion EQ is left as a white background. In this case, substantially only the different portions R1 to R3 and the frame lines K1 to K3 are printed. Compared with the case of FIG.
However, the confirmation of the relationship between the coincident portion EQ and the different portions R1 to R3 is inferior due to the absence of the image, but the advantage is that the printing speed is high because the image portion to be output is substantially small, and the ink consumption is small. There is.

<Parallel Extraction of Pixel Information and Elimination of Different Parts (Overview)> Next, when performing plate inspection as described above, the operator details the image contents of the different parts R1 to R3 on the screen SC. A description will be given of a particularly improved configuration and operation for studying the above. This improvement includes "parallel extraction of pixel information" and "elimination of different parts", the outlines of which are as follows.

(A) "Parallel extraction of pixel information": This is because the old-version image P1, the new-version image P2, This is a function of automatically positioning the cursor at a position corresponding to each other in the area identification image CM2 and displaying a density value or the like for each color component at that position (FIG. 1).
1). That is, the operator sets the different part R1 on the screen SC.
When it is not possible to determine a delicate color difference or the like simply by viewing and viewing the image of R3, it may be desirable to compare the tone value and color component value of the pixel of interest as numerical values. The function that enables appropriate selection of pixels to be compared and their image information to be compared is “parallel extraction of pixel information”.

(B) "Erase different parts": This is to make it possible to identify which of the plurality of different parts R1 to R3 has already been enlarged and checked on the screen by displaying the area specified. This is an improvement (FIGS. 15 and 16).

These will be described in detail below.

<Parallel Extraction of Pixel Information> FIG. 11 is for the operator to visually check the contents of the different portions R1 to R3 and check whether or not the correction has been correctly made in the process of correction from the old version to the new version. An image example is shown. This is a screen that switches according to the menu selection of the operator after the image generation of FIG.

On the screen of FIG. 11, the old version image P1, the new version image P2, the area identification image CM2, and the difference frame image CM
B are displayed as windows, respectively, and an enlarged image display window LW and a pixel information display window PW
Is displayed. The details of the display contents of the enlarged image display window LW and the pixel information display window PW are shown in FIGS. 12 and 13, respectively. In the area identification image CM2 in FIG. 11, the white mask is selected as “strongest”, and thus the area identification image CM2 is selected.
The matching part EQ of No. 2 is substantially a white background (corresponding to the case of FIG. 10).

The flow of this "parallel extraction of pixel information" will be described with reference to the flowchart of FIG. The operator uses the mouse 182 to change the old-version image P1 in FIG.
New version image P2, area identification image CM2, difference frame image CMB
A small rectangular target frame TGa, TG
b, TGc, or TGd,
A range to be enlarged and displayed is specified (step S101).
At this time, when the target frame (eg, TGa) on one of the images P1, P2, CM2, and CMB is moved by the mouse 182, the corresponding target frames TGb, TGc, and TGd follow the remaining display images. Then, it automatically moves to the corresponding pixel position. Such an operation of moving the target frame from any of the images P1, P2, CM2, and CMB is similar to a following operation (described later) when moving the cross cursor on the partially enlarged image.

The target frames TGa, TGb, TGc, T
When the position of Gd is designated in this way, the old version image P
1. For the new edition image P2 and the area identification image CM2, the images in the target frames TGa, TGb, and TGc at that time are the images P1 and P in the image disk 170, respectively.
2 and CM2, the enlarged images P1L, P2L, and CM2L corresponding to them are displayed in parallel in the enlarged image display window LW of FIG. 12 (step S1).
02). Hereinafter, the enlarged images P1L, P2L, and CM2L are referred to as an "old version enlarged image", a "new version enlarged image", and an "identified enlarged image", respectively.

When "spoid mode" is selected from a menu (not shown) on the screen SC, the operator uses the mouse 182 to move the pointer PT (FIG. 12) on any of the enlarged images P1L, P2L, and CM2L. Can be moved, but at that time it is determined which enlarged image the pointer PT is currently over (step S1).
03). Then, a cross cursor is generated on the enlarged image with the position of the pointer PT at that time as a designated point (cross intersection).

For example, when the pointer PT is located on the old-version enlarged image P1L as shown in FIG. 12, a cross cursor CS1 having the pointer PT is generated on the old-version enlarged image P1L. When the pointer PT is located on any of the enlarged images P1L, P2L, and CM2L, the cross cursor replaces the display of the pointer PT, so that it appears as if only the cross cursor is moved on the enlarged image. . Therefore, specifying the position of the pointer PT on the old version enlarged image P1L by the operator is substantially equivalent to specifying the cross cursor CS1 on the enlarged image P1L.

Then, in addition to the enlarged image P1L at which the pointer PT exists at the time, the other two enlarged images P2L,
Cross cursors CS2 and CSM having designated points at respective corresponding positions of CM2L are automatically generated following the position of the cross cursor CS1 (step S105).

Then, those cross cursors CS1, C
The values of the color components in the old-version image P1 and the new-version image P2 are displayed in parallel in the pixel information display window PW (FIG. 13) for the pixel at the designated point in S2 and CSM by a numerical sequence (step S106). In the example of FIG.
Each value is shown in 256 gradations (8 bits) from 0 to 255 for the GB color component. Of these, the color component values of “old” and “new” are the pixel information of the corresponding pixels in the old image P1 and the new image P2, respectively, and “increase / decrease” is the pixel information of the corresponding pixels in the area identification image CM2. That is, the difference value of the color component value between the old version image P1 and the new version image P2 is shown. Also, these are YM
It is also possible to perform CK display, in which case it is displayed in halftone%.

The cross cursor CS in the enlarged images P1L, P2L and CM2L is displayed in the pixel information display window PW.
The information CRD of the relative coordinates (X, Y) of the designated points of 1, CS2 and CSM can also be displayed. This numerical value may be in pixel units, and is the distance unit in actual plate (mm, inch)
May be displayed. All enlarged images P1L, P2
Since it is guaranteed that the cross cursors CS1, CS2, and CSM are located at the same position in L and CM2L, it is sufficient to display only one set of the values of the relative coordinates (X, Y).

The position of the target frame TGa is kept as it is, and the operator moves the pointer PT (therefore, the cross cursor CS1).
Is moved to an arbitrary position on the enlarged image P1L of the old version, the designated points of the other cross cursors CS2 and CSM are also automatically moved to the corresponding positions on the enlarged images P2L and CM2L, and the old version at the new position. Pixel information of the image P1 and the new image P2 and their difference information are displayed in parallel in the pixel information display window PW (steps S107 to S11).
0).

It should be noted that, since the pointer PT is moved from one enlarged image (for example, old version enlarged image P1L) to another enlarged image (for example, new version enlarged image P2L), there is a step between steps S108 and S109. S103
The same steps as those described above are performed, but illustration is omitted in FIG. In the above description, the pointer PT is located on the old version enlarged image P1L.
The same applies to the case where it is on 2L or the enlarged identification image CM2L. For example, when the pointer PT is on the enlarged image P2L of the new edition, the designated point of the cross cursor CS2 moves to the position of the pointer PT, and the designated point of the cross cursor CS1 on the enlarged image P1L of the old edition follows. The designated points of the cross cursor CSM on the enlarged image CM2L move to the corresponding positions, and their pixel information is displayed in parallel.

As described above, the operator determines the appropriateness of the image correction while positioning the designated point of the cross cursor at a desired position in the enlarged image area and confirming the pixel information appropriately.

As described above, in the pixel information display window PW, the image information of the old version enlarged image P1L, the new version enlarged image P2L, and the identification enlarged image CM2L are displayed in parallel for the pixels corresponding to each other. Enlarged images P1L, P2L, CM
In any of the 2Ls, the cross cursor can be positioned by the mouse 182, so that a pixel of interest can be selected from any of these three types of images.

Then, the cross cursors CS1, CS2, CS
Since it is possible to extract image information in parallel while automatically following each other in synchronization with M, image information at a common position (pixel) for three types of enlarged images P1L, P2L, and CM2L In order to judge the suitability of image correction by comparing with each other, it is not necessary to individually position the cursor, and it is also possible to prevent a positioning error due to an operator's unfamiliarity. For this reason, the accuracy and speed of plate inspection can be improved.

The target frames TGa, TGb, TG
When c and TGd are moved to another area, the movement is
4, the target frame TG
The same inspection can be performed on the area indicated by the new positions of a, TGb, TGc, and TGd.

<Erase of Different Parts> Next, "eradication of different parts" will be described with reference to the flowchart of FIG.

As shown in FIG. 11, in order to know where the different parts R1 to R3 are located in the image, it is sufficient to refer to the area identification image CM2 and the difference frame image CMB on the screen SC.
However, in general, the difference between the old version and the new version is often only one, and usually a plurality of sections exist in one image. The number of different parts in a complicated edited image is considerably large.

At this time, the operator enlarges and displays each of the different parts one by one to check the correction contents. If the number of different parts is large, any of the different parts is already enlarged to the enlarged image display window LW. In some cases, it may be forgotten as to whether the display has been completed and the correctness inspection has been completed. Then, although the correctness inspection has already been performed, the different portion is selected and enlarged and displayed again, resulting in wasted time.

Conversely, when it is erroneously determined that the inspection has been completed for a different portion that has not yet been subjected to the correction appropriateness inspection, there is a possibility that the plate inspection may be terminated without sufficient inspection.

For this reason, the plate inspection apparatus 100 of this embodiment
Then, once you specify the area, the enlarged image display window L
For the difference portion enlarged and displayed on W, a predetermined area designated display is given on the difference frame image CMB as one of the plate inspection result images. Various displays can be adopted as the area-specified display. In the apparatus 100 of this embodiment, mask processing is performed to fill the area specified to be enlarged in a predetermined manner.

That is, as shown in FIG. 15, the target frame TGd moves as indicated by the dotted line according to the drag of the mouse 182, and the position of the target frame TGd at the time when the operator releases the button of the mouse 182 (in the illustrated example, the position differs from the position of the target frame TGd). The unit mask MS is generated and displayed on the section R1).
The unit mask MS has a predetermined color (for example, light gray).
The background color (for example, black) shown by hatching in FIG. 15 is overwritten, but only the frame lines K1 to K3 (for example, red frame line) are transmitted. In the area in which such a unit mask MS is generated, the old image P1, the new image P2, and the area identification image CM2 corresponding to the area are enlarged and displayed in the enlarged image display window LW, and the operator performs an enlarged visual inspection. And so on, the region to which this unit mask MS is assigned is “region designated”.
It turns out that.

However, with respect to the different portion R1 in the illustrated example, a fill mask MS1 as an area designated display covering the different portion R1 can be obtained by specifying the unit mask MS once.
Since the size of the different portion R2 is larger than that of the unit mask MS, it is not possible to enlarge and display the entire different portion R2 by a single region designation using the unit mask MS. Therefore, in this different part R2, by specifying the unit mask MS at a plurality of positions, a fill mask MS2 as a logical union set thereof is generated as shown in FIG.

Such a mask as an area-specified display is additionally displayed at that position each time the target frame is positioned, and if the latest state is maintained, the visual inspection is completed in any area. Can be easily checked.
In the enlarged image display window LW, any part of the whole image can be enlarged and displayed. However, since the region where the enlarged display is important is substantially the different parts R1 to R3, the operator can display the different parts R1 to R3. Select in any order and use mouse 1
If the target frames are sequentially moved to them by using 82, the filling masks MS1, MS shown in FIG.
2, MS3 will be displayed in an arbitrary order, and it can be seen that the enlarged visual inspection of all the different parts R1 to R3 has been completed at the time of FIG.

On the other hand, when only the fill mask MS1 is displayed as shown in FIG.
To R3, the enlarged display inspection has been completed for one of the different portions R1, but the enlarged display inspection has not been completed for the remaining different portions R2, R3. , R3 can be reliably performed without forgetting.

The mask as the area designated display may be displayed only on the different portions R1 to R3, but in this embodiment, the area where the images of the old version P1 and the new version P2 match (the matching section) The mask portion protruding above the region of (EQ) is also displayed on the screen.

FIG. 17 is a flowchart showing the above process. For example, when an area is designated by moving the target frame TGd on the difference frame image CMB, the old image P1, the new image P2, and the area identification corresponding to the area are designated. Image CM
2 are displayed in the enlarged image display window LW (steps S101 to S2).
02), an area designated mask (for example, SM1) is generated and displayed at that position (step S203).

In the apparatus 100 of this embodiment, not only the area designated display is performed as described above, but also any one of the operator difference parts R1 to R3 can be marked. Has become. That is,
For example, when the operator clicks on the “remember check” column CK in the enlarged image display window LW in FIG. A predetermined display such as a “レ” mark is added to a different portion corresponding to the area displayed in an enlarged manner. The “レ” mark given to the different portion R3 in FIG. 16 is the marking provided in this manner. Then, by referring to the marking later, the operator can take necessary measures such as making the different portion R3 a target of plate re-correction processing (steps S204 and S205).

Note that this "check" can be used by the operator with any meaning, and is not limited to the above-mentioned use method. In addition, for a different portion to which a fill mask is added or a different portion specified by an operator as a “check” target, the flag indicating that “mask added” or “checked” is included together with the position information of the area. It may be expressed and stored together with the image file on the image disk 170 (for example, the image file of the new version image P2).

In this way, even if the power of the plate inspection apparatus 100 is turned off, when the image file of the new version image P2 is read or transferred as necessary, each different part R1 is read.
The marked area of the different parts R1 to R3 can be distinguished from other areas by the completion status of the enlarged display inspection for R3 to R3 and the “check”.

[0102]

[Modifications] Although one embodiment of the present invention has been described above, the present invention can be implemented with various other modifications, and examples of such modifications are as follows.

It is not essential that the operator can select which of the old version image P1 and the new version image P2 is to be displayed in the different portions R1 to R3, and one of them is fixedly displayed. May be set. In that case, the new version image P
It is more preferable that 2 is displayed.

The new version image P is included in the different portions R1 to R3.
In the case of displaying No. 2, the same image as the new version image P2 itself may not be displayed, but may be processed to reduce the number of colors, for example.

The enlarged display of each different part and the assignment of the area designated mask may be sequentially performed according to a predetermined rule in accordance with the magnitude of the coordinate value of each different part on the screen SC.

For example, as shown in FIG. 18A, the main scanning direction (horizontal scanning direction) H and the sub-scanning direction (vertical scanning direction) V on the screen SC of the display 140 are two-dimensional coordinate axes. The coordinate values of the upper left corner of the frame line K indicating each of them are specified, and they are used as position information in FIG.
Is stored in the image disk 170 of the image forming apparatus.

Then, labeling is performed on each different part so that the main scanning coordinates H of the screen SC are selected in order from the smallest coordinate value to the larger one, and the sub-scanning coordinates V are also selected sequentially from the smaller value to the larger coordinate value. deep.

The enlarged image display window LW includes a button J of "jump to next different part" as shown in FIG.
P is provided, and each time the mouse is clicked with the mouse 182, the different part is sequentially selected in accordance with the above-described coordinate value order rule. However, when one size of the target frame (which is equal to the size of the unit mask MS) cannot cover one different part, FIG.
As in the case of the different part R2, the operator moves the target frame to a plurality of positions and sequentially enlarges and displays each of the areas. Can be covered.

That is, the movement of the target frame between the different parts proceeds in a predetermined order as indicated by the arrow AR, and the position of the enlarged display can be arbitrarily designated near each of the different parts. Note that a dotted line portion of the arrow AR indicates a portion that has not yet received a jump command.

The flowchart in the case of the above modification is shown in FIG.
9. Step S30 shown here
In steps S303 to S304, if there are a plurality of different parts having the same sub-scanning coordinates, the order of jump is determined by the magnitude of the main scanning coordinates, and one different part having the same sub-scanning coordinates is determined. Indicates that it is adopted as the next jump destination.

In the above embodiment, three types of enlarged images are displayed in the enlarged image display window LW in FIG. 12, but at least two types of images are displayed in terms of visual comparison of images and parallel display of pixel information. It should just be displayed. When displaying two types of enlarged images, two cursors that move on the enlarged image in synchronization with each other are sufficient. The form of the cursor is not limited to the cross cursor.

The pixel information displayed in the pixel information display window PW may not be a numerical display but may be a geometric display using a graph or the like.

● Rectangular frame line K1 surrounding different portions R1 to R3
A frame line of another shape, for example, a circle, an ellipse, or the like may be used instead of ~ K3. However, using a rectangle makes it easier to match the outer shape of the image component, and it is easier to create a figure. The same applies to the shape of the mask SM as the area designated display of each different part.

● Matching part E in the area identification image CM2
When a white mask is not applied to Q, it is necessary to display a boundary between the different portions R1 to R3 and the matching portion EQ, as indicated by the frame lines K1 to K2, but the matching portion EQ has a white mark. When the matching portion EQ and the different portions R1 to R3 can be distinguished only by applying a mask or displaying only the matching portion EQ in a specific color, it is not possible to add a frame line to the region identification image CM2. Not required.

The fill mask of the area designated display of the different portion is added to the difference frame image CMB, but may be added to another plate inspection result image (frame image CM1 or area identification image CM2). For example, "Done" instead of a fill mask
Marking may be performed.

The present invention can also be applied to a case where a digital image is printed out by a proof printer, and how much the printed image differs from the original digital data due to a printing error or the like. In this case, the print image is read photoelectrically and used as image data to be compared.

● Comparing the pixel information of the corresponding pixels among a plurality of images with each other is performed not only in the plate inspection apparatus in the plate making process but also in many image processing apparatuses such as graphic processing and CAD. The present invention can be generally extended to such an image processing apparatus.

[0118]

As described above, according to the first to ninth aspects of the present invention, the first and second cursors on the first and second display images follow one another and follow the other. Can follow the corresponding position and display the pixel information at each of the corresponding pixels, so that it is not necessary to position the cursor of each of the two images separately.

Therefore, the position designation using the cursor is simplified, and there is no danger of erroneously designating pixels that do not correspond to each other.

Therefore, according to the present invention, the plate inspection work can be made more efficient. According to the eighth and ninth aspects of the present invention, it is possible to efficiently perform image comparison in various types of image processing.

In particular, according to the second aspect of the invention, since the position can be designated by the cursor from either side of the first and second images, the degree of freedom in the designation of pixels by the operator is increased.

Further, according to the third aspect of the present invention, the portion corresponding to the first and second display images in the plate inspection result image is also displayed as the third display image, and any of the first to third images is displayed. Even if the cursor position is specified above, since the respective cursor positions follow the remaining display images, it is possible to specify the position from which pixel information should be extracted from any of these three images.

[Brief description of the drawings]

FIG. 1 is a block diagram of a plate making system 1 including a plate inspection device 100 according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of an old image P1 and a new image P2 to be inspected by the plate inspection apparatus 100.

FIG. 3 shows a combination of a flow executed by software in an arithmetic control unit 120 and a data generation stage,
FIG. 6 is a diagram showing a plate inspection operation in FIG.

FIG. 4 is a diagram illustrating a situation where an old version image P1 and a new version image P2 are each divided into a small rectangular block set {Bij}.

FIG. 5 is an explanatory diagram of a situation in which a different portion is defined as a rectangular area including an adjacent set of blocks corresponding to a mismatched portion between an old version image P1 and a new version image P2.

FIG. 6 is an explanatory diagram of a display example on a screen SC of a color display.

FIG. 7 is an enlarged view of the dialog DLG of FIG. 6;

FIG. 8 is a diagram illustrating an example of a framed image CM1 and a difference frame image CMB.

FIG. 9 is a diagram illustrating an example of a comparison result image CM2 to which a white mask has been applied.

FIG. 10 is a diagram illustrating an example of a comparison result image CM2 in which a matching portion EQ is set to a white background by a strong white mask.

FIG. 11 is an explanatory diagram of a display example on a screen SC of a color display.

FIG. 12 is an enlarged view of an enlarged image display window LW of FIG. 11;

FIG. 13 is an enlarged view of a pixel information display window PW of FIG. 11;

FIG. 14 is a flowchart showing an operation of following a cursor and an operation of extracting pixel information in parallel.

FIG. 15 is an enlarged view of the difference frame image CMB of FIG. 11;

FIG. 16 is an enlarged view of another stage of the difference frame image CMB of FIG. 11;

FIG. 17 is a flowchart showing an operation for erasing a different part.

FIG. 18 is a diagram showing another example of the operation of erasing a different part.

FIG. 19 is a flowchart showing a modified example of the operation of erasing a different part.

[Explanation of symbols]

1 Plate Making System 100 Plate Inspection Device P1 Old Version Image P2 New Version Image CM1 Border Line Image (one of inspection result images) CMB Difference Frame Image (one of inspection result images) CM2 Comparison Result Image (one of inspection result images) EQ Matching part between old version image P1 and new version image P2 Bij image divided block R1 to R3 Different part between old version image P1 and new version image P2 K1 to K3 Frame line PW Pixel information display window LW Enlarged image display window CS1, CS2, CSM Cross cursor P1L Enlarged image of old version, P2L Enlarged image of new version CM2L Enlarged image for identification TG, TGa to TGd Rectangular target frame MS1, MS2, MS3 Fill mask with specified area MS Unit display mask

Claims (9)

[Claims] 1. A plate inspection device for comparing and inspecting first and second images obtained in a plate making process, wherein: (a) regions of the first and second images corresponding to each other are defined by a predetermined number; Display means for displaying on the screen as first and second display images; (b) operation means for specifying the position of a cursor displayed on the screen; and (c) first and second display images. A cursor following means for following a second cursor to a corresponding position on the other display image in accordance with a designated position of the first cursor on one of the display images, and (d) the designation of the one display image A plate information display control unit that causes the display unit to display first pixel information at a position and second pixel information at the corresponding position of the other display image on the display unit. apparatus. 2. The apparatus according to claim 1, wherein the one of the display images is any one of the first and second images, and the second display image is displayed on the other display image in accordance with the first cursor. A plate inspection device characterized in that a cursor follows. 3. The apparatus according to claim 1, wherein the first and second image inspection result images of the first and second images are included in the first and second image inspection result images.
And a portion corresponding to the second display image is also displayed on the display means as a third display image, the cursor following means includes: i) a position of the first cursor on the one display image; ) The position of the second cursor on the other display image, and iii) the position of the third cursor on the third display image. Means for following the corresponding position on the display image of the plate. 4. The plate inspection apparatus according to claim 1, wherein the display unit further displays difference information between the first and second pixel information. . 5. The device according to claim 1, wherein the first and second images are color images, and the first and second pixel information is a color image of each color component in the pixel. A plate inspection device comprising information according to size. 6. The apparatus according to claim 1, wherein at least one of the first and second images is obtained by developing a pixel in a digitally edited image in a digital state. A plate inspection device, characterized in that the plate inspection device is used. 7. The apparatus according to claim 1, wherein at least one of the first and second images is obtained by photoelectrically reading an image of a plate on which exposure recording or printing recording is performed. Plate inspection device, characterized in that: 8. An image comparison apparatus for comparing a first image with a second image, wherein: (a) displaying, in the first image and the second image, areas corresponding to each other as first and second display images; Display means; (b) operating means for operating and moving a first cursor on the screen of the display means; and (c) the first cursor on one of the first and second display images. Means for causing the second cursor to follow a corresponding position on the other display image in accordance with the designated position by (d), (d) first pixel information at the designated position of the one display image, and the other display An image processing apparatus, comprising: pixel information display control means for causing the display means to display second pixel information at the corresponding position of an image on the display means. 9. A computer, comprising: (a) display means for displaying, as first and second display images, areas corresponding to each other with respect to the first and second images; and (b) on a screen of the display means. Operating means for operating and moving the first cursor; (c) corresponding to a position specified by the first cursor on one of the first and second display images on the other display image, Means for causing a second cursor to follow the position; (d) first pixel information at the designated position of the one display image, and second pixel information at the corresponding position of the other display image. A computer-readable recording medium storing a program for causing the apparatus to function as a device including: a pixel information display control unit for displaying on the display unit.