JPH0798755A - Image processor - Google Patents

Abstract

PURPOSE:To provide the image processor capable of making an image condition correcting work efficient without degrading image quality. CONSTITUTION:This processor is provided with an image data storage means 11 in which an original image is stored, a table data storage means 12 for allowing a management number of the original image and a look-up table to correspond to each other and storing them, a selecting means 13 for selecting the original image from the image data storage means 11, a table management means 15 for fetching the look-up table corresponding to the original image selected by the selecting means 13, and also, writing the look-up table whose retention is requested in the table data storage means 12 together with the management number, and a table setting means 16 for changing the look-up table fetched by the table management means 15 and setting the look-up table to the original image selected by the selecting means 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus used for tone correction of an image in a design system, a layout scanner system and the like, and more particularly to an image processing apparatus for performing tone correction using a look-up table. .

[0002]

2. Description of the Related Art In the field of color printing, a layout scanner system is used as a device for saving the work of plate collection and facilitating various creative works (image processing, etc.).

FIG. 6 shows a configuration example of a general layout scanner system. In this layout scanner system, color image data is input from the image input device 1 such as an input scanner, and character data is input from the character input device 2. The data from these input devices 1 and 2 is temporarily stored in the memory of the system body 3. Then, the plate collection work is performed from the image data, the character data, the layout information, etc. read from the memory, and the created image is displayed on the display 4
Display on top and make image corrections. After displaying the finally decided image on the display 4 and checking the condition,
The image data is converted into a color printer 5, an output scanner 6,
Output to the imagesetter 7 etc. according to the purpose.

The tone correction in the layout scanner system described above is performed according to the flow chart shown in FIG. That is, the processing image is selected from various input images stored in the magnetic disk or the like of the system body 3, and the processing area in the image is further selected.

Next, a look-up table for making a tone correction to the processing area is created. First, as shown in FIG. 8, a look-up table in which the change in gray value before and after the process is 0 is set. Once the look-up table has been initialized, the look-up table is created by appropriately changing the default setting to obtain the desired tone correction. FIG. 9 shows an example of the look-up table after the change. The look-up table shown in the figure is such that the halftone dot percentage of the highlight portion is raised and the halftone dot percentage of the shadow portion is lowered.
Such a look-up table is created for each color of C, M, Y, and K.

Next, the selected input image is passed through the look-up table set as described above to convert the density of one halftone dot for each pixel in the processing area, and as a result, The tone of the image changes.

On the other hand, since it takes time and effort to change the table after initial setting every time the tone is corrected, it is necessary to improve the efficiency of the table preparation work. Therefore, conventionally,
A typical look-up table for tone correction as shown in FIG. 10 is created in advance, this look-up table is selected according to the tone correction content, and some changes are made to the selected table. It is considered to be used.

In the field of color printing and the like, it is general to prepare a sample and deliver it to a customer (designer or the like) so that the correction content pointed out by the customer is reflected in the image. Correction instructions from this customer are issued multiple times until the final decision is made, so every time a correction instruction is given, the tone correction according to the correction content is given to the image for which the sample copy was first created. Will be added repeatedly.

[0009]

However, the contents of the correction made to the sample by the customer are "compared to" positive ".
I often want you to do so, so if you have repeatedly performed the tone correction work until then, you often need to re-input the original image with the scanner. This is because it is difficult to restore the image modified by the system because the history of image modification does not remain in the system.

Further, if the image correction process is repeated for one image, there is a problem that the quality of the image deteriorates.

The present invention has been made in view of the above circumstances, and it is possible to know the history of image corrections performed on the original image and easily return to a desired processing state. Moreover, it is an object of the present invention to provide an image processing apparatus capable of coping with a correction request without increasing the data storage amount and without causing image quality deterioration even when the number of corrections reaches a plurality of times.

[0012]

In order to achieve the above object, the present invention has taken the following means.

In the image processing apparatus according to the first aspect, the tone of the image is corrected by using a look-up table, the image data storage means in which the original image is stored, the management number and the look of the original image. A table data storage unit that stores an up table in association with each other, a selection unit that selects an original image from the image data storage unit, and a lookup table that corresponds to the management number of the original image selected by the selection unit. The table management means for fetching from the data storage means and writing the look-up table requested to be stored together with the management number of the original image in the table data storage means, and the lookup table fetched by the table management means are changed to make the selection. For the original image selected by means It has a configuration comprising a table setting means for setting a click-up table.

According to a second aspect of the present invention, in the structure of the first aspect, if the selecting means specifies a region for a part of the original image, the selected region is selected from the original image. If there is a request to store the lookup table created for the designated area by the table management means, the lookup table is stored in the table data storage means together with the management number of the designated area, and the designated area is selected by the selection means. If so, the lookup table for the designated area is taken out from the table data storage means.

According to a third aspect of the present invention, in the image processing apparatus according to the first or second aspect, the table data storage means has a plurality of lookup tables for one original image or one designated area. Remember
The table management means fetches all the look-up tables of the original image or the designated area selected by the selection means, and the table setting means looks up one of the look-up tables fetched by the table management means. The table is selected.

[0016]

The present invention exerts the following actions by taking the above means. In the image processing apparatus according to claim 1, when the original image stored in the image data storage unit is read out by the selecting unit for tone correction, the original image selected by the selecting unit is created in the past. The lookup table is retrieved from the table data storage means by the table management means. The lookup table taken out is changed by the table setting means. Then, the original image read by the selecting means is tone-corrected using the look-up table set by the table setting means. Therefore,
The lookup table created in the past to correct the tone of the original image is managed in units of the original image, and when revising the image that has been corrected in the past, the lookup table used when correcting the past image is used. The table is automatically read out.

In the image processing apparatus according to claim 2, 1
Regions can be specified for image modification of a part of one original image. When an area is designated for a certain original image, the image data of the designated area is extracted from the original image by the selecting means. The look-up table for the designated area selected by the selection means is retrieved from the table data storage means by the table management means. When a lookup table is set in the designated area by the table setting means, if there is a storage request, the lookup table is stored in the table data storage means together with the management number of the designated area. Therefore, the look-up table is managed for the entire area of the original image and each of the specific areas.

In the image processing apparatus according to claim 3, 1
A plurality of look-up tables are stored in the table data storage means for one original image or one designated area. When the original image or the designated area is selected by the selection means, all the look-up tables or one look-up table stored for the selected original image or the designated area are retrieved. Then, the look-up table is changed by the table setting means.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows functional blocks of an image processing apparatus according to an embodiment.

The image processing apparatus of this embodiment stores a plurality of original images and mask data in the image / mask data storage means 11 composed of an MO disk or a hard disk, and the LUT data storage means 12 stores each original image and specific area. The lookup table (corresponding to the mask range) is stored. Each original image stores a color-separated image for each color. The mask data is data for selecting a specific area from one image.

The selection means 13 selects the original image and the processing area stored in the image / mask data storage means 11. Upon receiving an original image selection request from the operator, the selection unit 13 reads the corresponding original image from the image / mask data storage unit 11 and inputs it to the tone changing unit 14. Further, the selection means 13 receives a partial area designation in the original image from the operator and extracts only the image data of the designated area. The selection of the designated area is performed using the mask data. That is, the original image having the designated area and the mask data of the designated area are read out,
Only the image data in the designated area is selected by processing the original image with the mask data.

The lookup table stored in the LUT data storage means 12 is managed by the LUT data management means 15. The LUT data management means 15 obtains the original number of the original image or the original number and the mask number of the designated area from the tone changing means 14, and creates the original image or the designated area in the past based on the management number. The lookup table is stored in the LUT data storage means 12
Read out from and supplied to the tone changing means 14.

The LUT setting means 16 changes the lookup table read from the LUT data storage means 12 to the tone changing means 14 and sets the lookup table to the tone changing means 14. The LUT setting means 16 changes the look-up table provided from the LUT data management means 15 to the condition changing means 14 according to the operation by the operator. Then, the look-up table which receives the setting instruction from the operator is set in the tone changing means 14.

An example of the configuration of the LUT data storage means 12 is shown in FIG.
Shown in.

The LUT data storage means 12 comprises a document number (phtno) of an original image, a mask number (maskno) which is a management number of a partial area, and table data for each color for each stored lookup table. LU
A T block is formed, and the LUT block is registered in the table creation order.

FIG. 3 shows mask data composed of a bit map of one frame of the original image. The mask data consists of 0 and 1 data, and the designated area is "1".
The area outside the designated area is represented by “0”. The mask number corresponding to the designated area shown in FIG. 3 is stored in the LUT data storage means 12.

Next, the operation of this embodiment configured as described above will be described with reference to FIG.

Upon receiving an image selection request from the operator, the selection means 11 reads the original image for which the selection request has been made from the image / mask data storage means 11 and inputs it to the tone changing means 14. Further, when an area is designated subsequent to the image selection request, the mask data of the designated area is read from the image / mask data storage means 11. Then, the image data of the selected image that has already been read out and the mask data are arithmetically processed to extract only the image data of the designated area.
If the mask data corresponding to the designated area is not stored, a desired mask is created on the spot.

On the other hand, when an image is selected by the selection means 11, the original number of the selected image is given to the LUT data management means 15. When a part of the original image is selected as the designated area by the selection means 11, the mask number of the mask data used for extracting the designated area is given to the LUT data management means 15.

When the LUT data management means 15 acquires the original number of the original image to be image-corrected or the mask number of the designated area to be image-corrected, it retrieves the corresponding LUT data from the LUT-data storage means 12. For example, when correcting the entire area of the original image, only the original number is searched and all LUT blocks having the same image number are searched. When the image of a part of the original image is to be corrected, all LUT blocks having the same document number and mask number are searched.

When the search for the LUT block is completed,
It is determined how many corresponding LUT blocks exist.
When the tone of the original image or the designated area selected this time is corrected for the first time, the corresponding block does not exist. Again 2
In the case of the third time, there is one, and in the case of the third or more times, there is a plurality.

If there is no corresponding LUT data, L
The UT data setting means 16 initializes the LUT data. When only one LUT data exists, the LUT data is input from the LUT data storage means 12 to the read tone changing means 14. When there are a plurality of LUT data, the LUT data is registered at the rearmost of the LUT data storage means 12 (latest).
The LUT data is read from the LUT data storage means 12 and input to the tone changing means 14.

Next, the LUT input to the tone changing means 14.
LUT data is changed based on the data to create a desired look-up table. The change of the LUT data is performed by the LUT data setting means. For example, in FIG.
It is assumed that the lookup table in which the density of the highlight portion is increased is called as shown in FIG. In this case, if it is desired to reduce the density of the shadow part while keeping the density of the highlight part of the current image unchanged, the data is changed so that the density of the shadow part is decreased (modification example 1). If it is to be returned to the input state, the density of the highlighted portion is lowered (Modification 2). That is, the operator can easily determine what kind of tone correction is applied to the current image by looking at the read-out look-up table.

As described above, when the look-up table is changed according to the tone correction for the entire area or the predetermined area of the desired image, the look-up table is set in the tone changing means 14.

The tone changing means 14 tone-corrects the image data of the entire area or the designated area of the image selected by the selecting means 13 by using the look-up table set as described above.

On the other hand, when the operator requests the LUT data management means 15 to store the look-up table used for the tone correction, if the LUT data management means 15 specifies the original number and area of the image, Get the mask number. And manuscript number, mask number, LU
The T data is registered in the end of the LUT data storage means 12 in the form of a set of LUT blocks.

As described above, according to this embodiment, the input image is stored in the image / mask data storage means 11, and the look-up table used for tone correction is made to correspond to the original number of the image or the mask number of the designated area. When the same original image or the designated area is selected after being stored in the LUT data storage means 12, the stored look-up table is read out and changed and used. The state can be easily returned to, and the correction load can be reduced. Further, since the processing history is saved, it is possible to easily return to the previous processing state. Furthermore, the processed image is not saved, but only the lookup table used for the process is saved and managed.
There is an advantage that the amount of data to be stored does not increase even if the processing is repeated. Further, since the original image is always processed regardless of the number of times of processing, it is possible to prevent the image quality from being deteriorated due to the increase of the number of times of correction.

In the above embodiment, when there are a plurality of relevant LUT blocks, only the latest look-up table is read out. However, a list of the relevant LUT blocks is displayed and selected from them. LUT data setting means 1 by reading one look-up table
It may be configured so as to be changed in 6.

[0040]

As described above in detail, according to the present invention, it is possible to know the history of image corrections performed on the original image, easily return to the desired processing state, and the number of corrections. It is possible to provide an image processing apparatus capable of coping with a correction request without increasing the amount of data stored and without causing image quality deterioration even in the case of multiple times.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an image processing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an internal configuration of LUT data storage means provided in the image processing apparatus shown in FIG.

FIG. 3 is a diagram showing an example of mask data.

FIG. 4 is a flowchart showing operation contents of the image processing apparatus shown in FIG.

FIG. 5 is a diagram showing a modification example of a lookup table.

FIG. 6 is a schematic diagram of a layout scanner system.

FIG. 7 is a flowchart of tone correction in the layout scanner system shown in FIG.

FIG. 8 is a diagram showing an example of an initially set lookup table.

FIG. 9 is a diagram showing an example of a changed lookup table.

FIG. 10 is a diagram showing an example of data of various lookup tables.

[Explanation of symbols]

11 ... Image / mask data storage means, 12 ... LUT data storage means, 13 ... Image / processing area selection means, 14 ... Condition changing means, 15 ... LUT data management means, 16 ... LU
T data setting means.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H04N 1/60 1/48 8420-5L G06F 15/66 N 4226-5C H04N 1/40 D 4226- 5C 1/46 A (72) Inventor Hisato Urase 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd.

Claims (3)

[Claims] 1. An image processing apparatus for performing tone correction of an image using a look-up table, wherein image data storage means in which an original image is stored is associated with a management number of the original image and a look-up table. Table data storage means for storing, selection means for selecting an original image from the image data storage means, and a lookup table corresponding to the management number of the original image selected by the selection means, from the table data storage means, Table management means for writing the look-up table requested to be stored together with the management number of the original image in the table data storage means, and the original image selected by the selecting means by changing the look-up table fetched by the table management means. Lookup table for The image processing apparatus being characterized in that comprising a table setting means for setting. 2. The selecting means selects the designated area from the original image if there is an area designation for a part of the original image, and the table management means makes a lookup created for the designated area. If there is a request to store the table, it is stored in the table data storage means together with the management number of the designated area, and if the designated area is selected by the selection means, a lookup table for the designated area is stored from the table data storage means. The image processing apparatus according to claim 1, wherein the image processing apparatus is taken out. 3. The table data storage means stores a plurality of look-up tables for one original image or one designated area, and the table management means stores the original image or designated area selected by the selecting means. 3. All the lookup tables are taken out, and the table setting means selects one lookup table from the plurality of lookup tables fetched by the table management means.
The image processing device according to item 1.