JP2002232701A - Image processor, image processing method, image processing program, and recording medium recording image processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processor which can generate reduced images in a short time, at a lower cost, from image data that were doubly-compressed with high compression efficiency or were sorted. SOLUTION: A filing device 101, in dealing with doubly-compressed image data, obtains first image compressed data by expansion when the first compression processing is carried out by dividing image data into prescribed pixel blocks and calculating a representative pixel value based on the ratio of pixels having a prescribed pixel value for each pixel block. Then, on the basis of the representative pixel value of the obtained data and the number of pixels having the prescribed pixel value, it calculates the average pixel value in each pixel block, and based on which reduced images are generated.

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 for creating a reduced image of filed image data in a filing system for filing image data.

[0002]

2. Description of the Related Art In recent years, with the advancement and speeding up of data processing technology and the lowering of the cost of storage means for storing data, documents to be kept important (original documents on which images and characters are displayed) are important. ) Or a filing system that digitizes documents, such as documents that may be used in the future, in paper form, converts them into image data, and stores them in a mass storage device. It is supposed to be.

In such a filing system, although a large-capacity storage device is inexpensive, an enormous storage capacity is required to store a digital two-dimensional image as it is. The image is compressed and stored in an image file. And
If necessary, the compressed image stored in the image file is read out, subjected to image decompression processing and restored to the original image, and then connected to a terminal device connected to the filing system or connected via a network or the like. The information is displayed on a display device of a personal computer.

Conventionally, in a terminal device connected to such a filing system or a display device of a personal computer, the stored image data is reduced in order to easily and visually determine the filed image data. Images (thumbnail images) are provided.

On the other hand, recently, in a filing system, image data received via a network may be filed to the filing system.

[0006] The image data received via the network has been subjected to a predetermined compression process, and a technique for creating a reduced image from the compressed image data is required. Japanese Patent Application Laid-Open No. 7-30747
Patent Application Laid-Open No. 9-198017
There is known an image processing device described in Japanese Patent Application Laid-Open Publication No. H10-26095.

[0007] As shown in FIG. 9, a compounding apparatus 10 described in Japanese Patent Application Laid-Open No. 7-30747 has a control unit 11 for controlling the entire apparatus and a compressed data for reading compressed data transmitted continuously. An input section 12 and EOL (EnOL) which is a line end code added to each line of the input compressed data.
d of Line) code, and a compressed data thinning unit 13 that outputs only compressed data of a predetermined line, a change point creating unit 14 that converts the compressed data passed from the compressed data thinning unit 13 into change point data, A reduced change point creation unit 15 that reduces the point data to a predetermined compression ratio, and a change point drawing unit 16 that expands the reduced change point data into decoded data are provided.
A reduced image is generated by thinning out predetermined lines in the main scanning direction and the sub-scanning direction.

The image processing apparatus 20 described in Japanese Patent Application Laid-Open No. 9-198017 compresses digital image data using a plurality of compression codes to create a reduced image.

As shown in FIG. 10, the image processing apparatus 20 includes a compressed image data memory 21 for temporarily storing compressed image data output from a compressed image file, and a compressed image data memory 21 for each compressed code included in the compressed image data. Is a length code indicating the number of continuation bits of the same pixel (hereinafter simply referred to as length code)
Alternatively, a code conversion table 22 for storing a relationship with a coordinate code (hereinafter, simply referred to as a coordinate code) indicating a pixel position.
And a code conversion unit 23 that searches the code conversion table 22 with each of the compressed codes constituting the compressed image data read from the compressed image data memory 21 and converts the code conversion table 22 into a length code or a coordinate code, and conversion by the code conversion unit 23. And an image restoring unit 25 that creates a reduced / enlarged image corresponding to the specified reduction / enlargement ratio from the length code or the coordinate code thus set, and displays the image on the display device 27 via the display buffer 26. I have.

The reduction / enlargement condition setting unit 28 is constituted by a man-machine device such as a keyboard, and is a means for inputting and setting reduction / enlargement conditions.

With such a configuration, the image processing apparatus 20
Is converted into a length code indicating a continuous bit length of the same pixel or a coordinate code indicating a pixel position for each compression code included in the compressed image data, and a reduced image is generated from the converted code. So, for example,
In the case of reduction to 1/2, in the length code, the number of continuous bits is set to half and replaced by a bit string. In the coordinate code, the coordinate value is simply set to half and replaced by a bit string. , A reduced screen is generated.

[0012]

However, recently,
Various compression methods have been developed for efficiently compressing image data. A typical method is to perform different types of compression processing twice (hereinafter referred to as double compression processing).
And a method of performing a compression process after rearranging pixels (hereinafter, simply referred to as a rearrangement process). In the method of generating a reduced image by the above-described compounding apparatus or image processing apparatus, It could not correspond to the double compression processing or the rearrangement processing.

Therefore, when generating a reduced image,
In the heavy compression processing, it is necessary to decompress the double compression processing and further perform the reduction processing, which takes a lot of time for the reduction processing, and also supports two types of compression methods in hardware. A longer expander is required, resulting in an increase in cost.

In the rearrangement process, the decompression process corresponding to the compression process must be performed, and the pixels must be rearranged based on the rearranged pixels. Even in this case, the reduction process requires much time. In addition, the cost of hardware has been increased.

The present invention has been made in order to solve such a conventional problem, and corresponds to double compression processing or rearrangement processing with high compression efficiency, and is inexpensive and short-time. It is an object of the present invention to provide an image processing apparatus capable of generating a reduced image from image data stored in a filing system.

[0016]

According to a first aspect of the present invention, there is provided an image processing apparatus according to the first aspect, wherein one image compression process in image data subjected to multiple image compression processes is performed by using the image data. Is divided into predetermined pixel blocks, and a representative pixel value is calculated based on a ratio of pixels having a predetermined pixel value for each of the pixel blocks. An image processing apparatus for generating an image, comprising: an acquiring unit that acquires data in which a representative pixel value for each pixel block is calculated in one of the image compression processes by performing a decompression process; and Average pixel value of each pixel block based on the acquired representative pixel value and the number of pixels having the predetermined pixel value in each of the obtained pixel blocks A calculating means for calculating for, has a configuration that includes a reduced image generation unit operable to generate a reduced image based on the average pixel value of each pixel block calculated by said calculating means.

With this configuration, the image processing apparatus according to the first aspect acquires the data in which the representative pixel value is calculated in one of the image compression processes by the acquisition unit, and the representative unit in the acquired data is acquired by the calculation unit. An average pixel value of each pixel block is calculated based on the pixel value and the number of pixels having a predetermined pixel value, and a reduced image is generated by the reduced image generation means based on the calculated average pixel value of each pixel block. .

Therefore, the image data which has been subjected to multiple compression processing divides the image data into predetermined pixel blocks, and calculates a representative pixel value based on the ratio of pixels having a predetermined pixel value for each pixel block. If the calculated and processed compression processing has been performed, a reduced image can be generated by obtaining data that retains the processed state, so that a reduced image can be generated from multiplexed compressed image data. When generating the image, there is no need to perform the decompression process in all compression processes, the reduced image generation process can be performed at high speed, and the image processing apparatus can be realized at low cost.

Further, the image processing device according to the second aspect of the present invention
Binarization processing means for binarizing image data;
A rearrangement processing unit that rearranges the image data binarized by the binarization processing unit for each pixel value; and a compression processing unit that compresses the data rearranged by the rearrangement unit. In an image processing apparatus that generates a reduced image in the processed image data,
Decompression processing means for performing decompression processing corresponding to the image compression processing of the compression processing means; division means for dividing the rearranged binarized data into predetermined pixel blocks; Calculating means for detecting each pixel belonging to the pixel block and calculating an average pixel value of each pixel block based on the detected number of pixels for each pixel block; and each pixel block calculated by the calculating means And a reduced image generating means for generating the reduced image based on the average pixel value of

With this configuration, the image processing apparatus according to the second aspect expands the image data that has been subjected to the image compression processing by the expansion processing means, and divides the expanded image data into predetermined blocks by the division means. Detecting each pixel belonging to each pixel block in the image data decompressed by the calculating means, calculating an average pixel value of each pixel block based on the detected number of pixels for each pixel block, The generation unit generates a reduced image based on the calculated average pixel value of each pixel block.

Accordingly, if the image data is binarized and the binarized image data is subjected to a compression process based on a rearrangement process for each pixel value,
Since a reduced image can be generated based on the data that has been subjected to the rearrangement processing by expanding the compressed data, the pixel values are rearranged when the reduced image is generated from the compressed image data. Therefore, the reduced image generation processing can be performed at high speed without performing the processing, and the image processing apparatus can be realized at low cost.

Further, the image processing apparatus according to claim 3 is
The invention according to claim 1 or 2, wherein the reduced image generating means has a configuration for generating a reduced image having gradation information.

With this configuration, the image processing apparatus according to claim 3 generates a reduced image having gradation information by the reduced image generating means.

Therefore, when the representative pixel value in each pixel block has gradation information and the gradation information is included in the average pixel value of each block calculated by the calculation means, the reduced image generation means Since the gradation information can be reflected on the generated reduced image, the reduced image generation processing can be performed at high speed, and the reproducibility of the compressed original image data can be improved.

According to a fourth aspect of the present invention, there is provided an image processing program according to the first aspect, wherein one image compression process of the image data subjected to the multiple image compression processes divides the image data into predetermined pixel blocks, A decompression process is performed by calculating a representative pixel value based on a ratio of pixels having a predetermined pixel value for each pixel block and generating a reduced image of the multiplexed image data. 1 of the image compression processing
Acquisition means for acquiring data in which the representative pixel value for each pixel block in one process is calculated, based on the representative pixel value and the number of pixels having the predetermined pixel value in each pixel block acquired by the acquisition means Calculating means for calculating an average pixel value of each pixel block; reduced image generating means for generating the reduced image based on the average pixel value of each pixel block calculated by the calculating means; and I have.

With this configuration, the image processing program according to claim 4 obtains data for which the representative pixel value has been calculated in one of the image compression processes, and obtains the representative pixel value and the predetermined pixel value in the obtained data. An average pixel value of each pixel block is calculated based on the number of pixels having a value, and a reduced image is generated based on the calculated average pixel value of each pixel block.

Therefore, the image data which has been subjected to multiple compression processing divides the image data into predetermined pixel blocks, and calculates a representative pixel value based on the ratio of pixels having a predetermined pixel value for each pixel block. If the calculated and processed compression processing has been performed, a reduced image can be generated by obtaining data that retains the processed state, so that a reduced image can be generated from multiplexed compressed image data. Does not need to perform decompression processing in all compression processing, and can perform reduced image generation processing at high speed.

According to a fifth aspect of the present invention, in the image processing program, the image data is binarized, the binarized image data is rearranged for each pixel value, and the rearranged data is processed. A computer that generates a reduced image in the image data that has been subjected to the image compression processing by performing compression processing on the image data, by performing expansion processing means that performs expansion processing corresponding to the image compression processing of the compression processing means; Dividing means for dividing encoded data into predetermined pixel blocks, detecting each pixel belonging to each pixel block divided by the dividing means, and detecting each pixel block based on the detected number of pixels of each pixel block. Calculating means for calculating an average pixel value of the reduced image based on the average pixel value of each pixel block calculated by the calculating means. It has a structure to function as a reduced image generation means for forming.

With this configuration, the image processing apparatus according to claim 5 expands the image data that has been subjected to the image compression processing, divides the expanded image data into predetermined blocks, Each pixel belonging to the pixel block is detected, and an average pixel value of each pixel block is calculated based on the detected number of pixels of each pixel block.Based on the calculated average pixel value of each pixel block, To generate a reduced image.

Therefore, if the image data is binarized and the binarized image data is subjected to a compression process based on a rearrangement process for each pixel value,
Since a reduced image can be generated based on the data that has been subjected to the rearrangement processing by expanding the compressed data, the pixel values are rearranged when the reduced image is generated from the compressed image data. Therefore, the reduced image generation processing can be performed at high speed without performing the processing, and the image processing apparatus can be realized at low cost.

According to a sixth aspect of the present invention, there is provided a recording medium on which the image processing program is recorded, wherein one image compression process in the image data subjected to multiple image compression processes divides the image data into predetermined pixel blocks. Along with
An image processing program for calculating a representative pixel value based on a ratio of pixels having a predetermined pixel value for each pixel block and generating a reduced image in the multiplexed image compression-processed image data by a computer. A recording medium on which recording is performed, obtaining means for obtaining data in which a representative pixel value for each pixel block is calculated in one of the image compression processes by performing decompression processing; Calculating means for calculating an average pixel value of each pixel block based on a representative pixel value in the pixel block and the number of pixels having the predetermined pixel value, based on an average pixel value of each pixel block calculated by the calculation means; A configuration in which an image processing program that functions as a reduced image generation unit that generates the reduced image is recorded. It has.

According to this configuration, the image processing program recorded on the recording medium according to the sixth aspect of the present invention can be used as one of the image compression processes.
Data in which the representative pixel value is calculated in one process is obtained, and the average pixel value of each pixel block is calculated based on the representative pixel value and the number of pixels having a predetermined pixel value in the obtained data. A reduced image is generated based on the average pixel value of each pixel block thus obtained.

Therefore, the image data which has been subjected to multiple compression processing divides the image data into predetermined pixel blocks, and calculates a representative pixel value based on the ratio of pixels having a predetermined pixel value in each pixel block. If the calculated and processed compression processing has been performed, a reduced image can be generated by obtaining data that retains the processed state, so that a reduced image can be generated from multiplexed compressed image data. Does not need to perform decompression processing in all compression processing, and can perform reduced image generation processing at high speed.

In the recording medium storing the image processing program according to the present invention, the image data is binarized by a computer, and the binarized image data is rearranged for each pixel value. And a recording medium storing an image processing program for generating a reduced image of the image data subjected to the image compression processing by compressing the rearranged data, and performing an expansion processing corresponding to the compression processing. Decompression processing means, dividing means for dividing the sorted binary data into predetermined pixel blocks, detecting each pixel belonging to each pixel block divided by the dividing means, and detecting each of the detected pixels Calculating means for calculating an average pixel value of each pixel block based on the number of pixels for each block; And a recorded constituting an image processing program for said reduced image generating means for generating a reduced image, to function as based on the average pixel value of each pixel block.

According to this structure, the image processing program recorded on the recording medium according to claim 7 expands the image data subjected to the image compression processing, divides the expanded image data into predetermined blocks, and expands the image data. Each pixel belonging to each pixel block in the obtained image data is detected, and an average pixel value of each pixel block is calculated based on the number of pixels detected for each pixel block. A reduced image is generated based on the average pixel value of.

Therefore, if the image data is binarized and the binarized image data is subjected to a compression process based on a rearrangement process for each pixel value,
Since a reduced image can be generated based on the data that has been subjected to the rearrangement processing by expanding the compressed data, the pixel values are rearranged when the reduced image is generated from the compressed image data. Therefore, the reduced image generation processing can be performed at high speed without performing the processing, and the image processing apparatus can be realized at low cost.

The image processing method according to claim 8 is
One image compression process in image data that has been subjected to multiple image compression processes divides the image data into predetermined pixel blocks, and based on a ratio of pixels having a predetermined pixel value for each of the pixel blocks. An image processing method for calculating a representative pixel value and generating a reduced image of the multiplexed image data that has been subjected to the image compression processing.
An acquisition step of acquiring data in which the representative pixel value for each pixel block in one process is calculated, and the number of pixels having the predetermined pixel value and the representative pixel value in each pixel block acquired in the acquisition step. A calculating step of calculating an average pixel value of each of the pixel blocks,
A reduced image generation step of generating the reduced image based on the average pixel value of each pixel block calculated in the calculation step.

With this configuration, in the image processing method according to the present invention, the obtaining step obtains the data in which the representative pixel value in one of the image compression processing is calculated, and the calculating step includes the representative data in the obtained data. An average pixel value of each pixel block is calculated based on a pixel value and the number of pixels having a predetermined pixel value, and a reduced image is generated based on the calculated average pixel value of each pixel block in a reduced image generation step. .

Therefore, the image data which has been subjected to multiple compression processing divides the image data into predetermined pixel blocks, and calculates a representative pixel value based on the ratio of pixels having a predetermined pixel value for each pixel block. If the calculated and processed compression processing has been performed, a reduced image can be generated by obtaining data that retains the processed state, so that a reduced image can be generated from multiplexed compressed image data. Does not need to perform decompression processing in all compression processing, and can perform reduced image generation processing at high speed.

The image processing method according to claim 9 is
The image data is binarized, the binarized image data is rearranged for each pixel value, and the rearranged data is compressed to reduce the image data subjected to the image compression processing. An image processing method for generating an image, comprising: an expansion processing step of performing expansion processing corresponding to the compression processing; a division step of dividing binarized data that has been rearranged into predetermined pixel blocks; Calculating each pixel belonging to each pixel block divided by the step, and calculating an average pixel value of each pixel block based on the detected number of pixels for each pixel block; and A reduced image generating step of generating the reduced image based on the calculated average pixel value of each pixel block.

With this configuration, the image processing method according to the ninth aspect expands the image data that has been subjected to the image compression processing in the expansion processing step, and divides the expanded image data into predetermined blocks in the division step. Detecting each pixel belonging to each pixel block in the image data decompressed by the calculation step, calculating an average pixel value of each pixel block based on the detected number of pixels of each pixel block, and generating a reduced image A reduced image is generated based on the calculated average pixel value of each pixel block by the process.

Therefore, if the image data is binarized and the binarized image data is subjected to a compression process based on a rearrangement process for each pixel value,
Since a reduced image can be generated based on the data that has been subjected to the rearrangement processing by expanding the compressed data, the pixel values are rearranged when the reduced image is generated from the compressed image data. Thus, the reduced image generation processing can be performed at high speed without performing the processing.

[0043]

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

First Embodiment FIGS. 1 to 4 show an image processing apparatus, an image processing method, an image processing program according to the present invention, and a first example of a recording medium on which a program thereof is recorded.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating an embodiment, which is an embodiment of a filing system using the image processing apparatus, the image processing method, and the image processing program.

First, the configuration of the filing system and the filing apparatus will be described with reference to FIGS.

FIG. 1 is a configuration diagram of a filing system according to the present embodiment, and FIG. 2 is a configuration diagram of a filing apparatus. Further, the filing apparatus according to the present embodiment constitutes a digital multifunction peripheral having functions such as a scanner, a copier, a facsimile, and a printer that take in image data.

The filling system 100 shown in FIG. 1 captures image information, stores the captured image information as image data, and refers to and operates image data stored in the filing device 101. The filing apparatus 101 and the PC 102 are constituted by a plurality of personal computers (hereinafter, referred to as PCs) 102 that issue instructions.
k) connected to each other by 103;

A filing device 101 shown in FIG. 2 records a data reading unit (scanner) 201 for reading image information necessary for a facsimile data transmission operation from a paper document, and records read data or received data stored therein. A writing unit (plotter) 202 for printing out on paper and a program for realizing the image processing function of the present embodiment are stored, and all of the input image data and various information (additional information) related to the image data are stored. A large-capacity storage device (HDD) 203 for storing, a readable / writable memory (hereinafter, referred to as RAM) 204, a read-only memory (hereinafter, referred to as ROM) 205, and image data (binary Image processing unit 206 for performing image processing such as image compression, and an operation display unit (operation panel) 207 used by a user to perform a predetermined operation. , LAN controller for controlling the transmission and reception of data in LAN 103 (or, a network interface card (NI
C)) 208, a modem 209 for controlling transmission and reception of data to and from a public line, a network control unit (NCU) 210 for detecting and analyzing a DTMF signal, and executing programs such as control stored in a ROM 205. A central processing unit (hereinafter referred to as a CPU) 211 for controlling the operation of the entire apparatus is provided.

The scanner 201 reads image information necessary for a facsimile data transmission operation from a paper document, and outputs the read image information to the image processing unit 206.

The plotter 202 prints out the read data stored in the HDD 203 or the received data received via the LAN 103 and the public telephone network on recording paper.

The HDD 203 stores a program for realizing the image processing function of the present embodiment. The HDD 203 reads facsimile image data from the LAN 103 or a public telephone network, and reads a predetermined image by the scanner 201. This is a large-capacity recording medium for storing all processed image data and various information (additional information) related to the image data.

Incidentally, such a recording medium is not limited to the HDD, but may be a memory, a floppy (registered trademark).
Disc, MD (Mini Disc), MO (Magneto-Optical)
Discs), DVDs (Digital Versatile Discs), and recording media such as CDs (Compact Discs) may be used.

The RAM 204 is a memory for temporarily storing data required for facsimile control and filing control, and for performing protocol processing for network control. Further, the ROM 205 stores control procedures such as a facsimile control procedure and a network control procedure.

The image processing unit (IPU) 206 includes the scanner 201
In addition to compressing and encoding the read binary image, double image compression processing (hereinafter, referred to as first image compression processing and second image compression processing) is performed as necessary. Further, the image processing unit 206 outputs the compressed image data to the HDD 203.

Further, the image processing unit 206 is connected to the network 1
03 so that the plotter 202 can print the compression code of the image data received via the public telephone line network.
Decoding into a value image is also performed.

In this embodiment, of the double compression processing, the first image compression processing includes the technique previously submitted by the present applicant (the technique disclosed in Japanese Patent Application No. 2000-92393).
Is used.

In this first image compression processing, the read image data is divided into a plurality of blocks each composed of N pixels × M pixels, and each pixel block is divided into two groups with the average value of the entire pixel values as a threshold value. A small group is generated for each group using the average value of each group as a threshold value, and the average of the pixel values in each small group is determined based on the average value of the pixel group having the maximum average value and the minimum average value of the pixel group. Is used as a representative pixel value, and compression processing is performed based on the representative pixel value and a code indicating the position of each pixel. For example, data 300 of each pixel block in the image data shown in FIG. 3 is generated by the first image compression processing (hereinafter, referred to as first compressed image data).

FIG. 3 is an example showing the data structure of the generated first compressed image data in a pixel block. A-high 301 is a representative pixel value having the maximum average pixel value of each pixel block. −low302 is a representative pixel value having the minimum average pixel value of each pixel block, and when the original image data is a monochrome image, the pixel value of A-high301 is
In addition to showing the pixel value of the black image without limit,
The pixel value of −low302 indicates the pixel value of the white image without limit. In the case of having a halftone, each A-high301
The pixel values of A-low 302 and A-low 302 indicate half-tone pixel values. Therefore, a code indicating the position of each pixel
With 303, the original image data can be reproduced.

In the second image compression processing, the first compressed image data generated by the first image compression processing is
A-high 301 and A-low 302 are representative pixel values, and a code 30 indicating the number of pixels and the pixel position of each pixel block.
Based on the above, each pixel value is replaced with this representative pixel value to generate predetermined image data (representative pixel value data), and the generated representative pixel value data is compressed. For example, this compression processing uses an MH coding scheme (Modified Huffma) using a distribution of white or black signals.
n Code) or a two-dimensional coding method (MR coding method) in which the correlation between scanning lines is enhanced.

The compression processing is not limited to the MH coding method and the MR coding method.

An operation display unit (operating panel) 207 includes a key group such as a numeric keypad and a start / stop key, and a display for displaying an operation screen or an operation mode.
An input / output unit used by a user to operate the filing apparatus 101.

The LAN controller 208 connects the PC 102 (or an external communication terminal device) to the filing device 101, decodes data received from the network (LAN) 103, and encodes data to be transmitted to the network 103. This is a network control LSI that performs transmission and reception frame buffering.

After reading the data, the modem 209 modulates the binary coded image information so that it can be transmitted to a public line such as the PSTN, and modulates the modulated image information from the other party. The demodulation for returning the code to the original binary code is performed.

The network control unit (NCU) 210 is a detector for detecting and analyzing a DTMF signal from the other party.

The CPU 211 executes software (such as a control program) stored in the ROM 205 and executes
1, control the operation of the entire device including the plotter 202,
The program stored in the HDD 203 is executed to generate a reduced image according to the present embodiment, and to hold and manage the reduced image in association with the stored image information.

Here, the principle of generating a reduced image in the present embodiment will be described. In the CPU 211, the reduced image is
It is generated from the data compressed by the above-described first image compression processing shown in FIG. 3, and the number of pixels of the pixel group H (A-high) having a high representative pixel value from the code and the representative pixel value The average pixel value of each pixel block is calculated by counting the number of pixels of the low pixel group L (A-Low) and performing the operation as shown in (Equation 1) together with the representative pixel values (A-high and A-Low). It is to be calculated. Average pixel value of pixel block = (A−high × number of pixels in H group + A−Low × number of pixels in L group) × 255 / total number of pixels in pixel block (1)

Therefore, the average pixel value of the pixel block calculated in this way is set to the pixel value of the pixel block, and the reduced image is generated by calculating the average pixel value of all the pixel blocks. .

In the present embodiment, a reduced image is generated by a program, but hardware means for generating a reduced image may be used. Further, it has means for detecting whether such hardware means is connected to the filing apparatus 101, and when the hardware means is connected, generates a reduced image by the hardware means, When the hardware means is not connected, it may be created by a program stored in the HDD 203.

On the other hand, although not shown in detail, the PC 102 has at least a CPU for controlling the entire apparatus, and temporarily holds necessary data for network control and image operation, or performs protocol processing for network control. And a ROM for storing a control program of the CPU, a network control procedure, and the like.
And an input device for instructing the filing device 101 to perform image operations and the like, a display device such as a CRT, a PC 102 (or an external communication terminal device), and the filing device 101. (Equivalent to the LAN controller 208) for data communication.

Next, the reduction processing operation of this embodiment will be described with reference to FIG.

FIG. 4 is a flowchart showing a reduced image creation processing operation. It is also assumed that a plurality of compressed image data have already been stored in the HDD 203 and have been filed. The image processing in the generation of the reduced image is performed by the JPEG method. Further, this operation is repeatedly performed in parallel with the main routine in the operation of the filing apparatus 101.

First, the HDD 211 is sent to the CPU 211 by the PC 102.
When a request to create a reduced image of arbitrary image data stored in the storage unit 3 is confirmed (step S1), the CPU 21
1 reads out the compressed image data from the HDD 203 (step S2), performs decompression processing corresponding to the second image compression processing to generate first compressed image data (step S3), and generates the first compressed image data. Is written in the RAM 204 (acquisition step (step S4)).

Next, the CPU 211 reads out the first compressed image data for each pixel block from the RAM 204 (for each data unit), and counts the number of pixels for each pixel block (step S5).

Next, the CPU 211 performs the operation of (Equation 1) (step S6), calculates the average pixel value of each pixel block, and writes it to the RAM 204 (calculation step (step S6).
7)).

Next, it is determined whether or not data (8 lines) for a predetermined line capable of performing the JPEG processing has been prepared (step S8).
5 and calculate the average pixel value of the next pixel block.
If it is determined that the data for a predetermined line has been collected, JPEG compression processing is performed (step S9).

Next, the compressed data obtained by the JPEG compression processing is written to the RAM 204 (step S1).
0), it is determined whether or not the pixel block whose average pixel value has been calculated in steps S5, S6, and S7 is the last pixel block in the image data (step S11). If it is not the last block, the process goes to step S5 to process the next pixel block. In the case of the last pixel block, the JPEG-compressed image data is written to the HDD 203 (step S12), and the process returns to step S1 (reduced image generation step).

In the present embodiment, a reduced image is generated in this manner. For example, a reduced image output to the HDD 203 is transmitted to the PC 102 to which a request to create a reduced image is issued from the HDD 203 in accordance with an instruction from the CPU 211. Is provided. Therefore, the PC 102 that has been requested to create a reduced image can display the reduced image on the display device.

When the user specifies the image data filed in the HDD 203 using the reduced image displayed on the PC 102 and requests a print process,
The PU 211 reads out the specified image data from the HDD 203, outputs it to the plotter 202, and prints it.

As described above, according to this embodiment, in the reduced image generation processing, it is possible to obtain the data for which the representative pixel value has been calculated in the first image compression processing, and this calculation means has obtained this data. Since the average pixel value of each pixel block can be calculated based on the representative pixel value in the data and the number of pixels belonging to the predetermined group, a reduced image is calculated based on the calculated average pixel value of each pixel block. Can be generated.

Therefore, the image data that has been double-compressed by the image processing unit 206 is divided into predetermined blocks, and the representative pixel value is determined based on the ratio of pixels having a predetermined pixel value for each pixel block. Is calculated and processed, the reduced image can be generated by obtaining the data holding the processed state, so that the double compressed image data When generating a reduced image, there is no need to perform expansion processing in all compression processing, and the reduced image generation processing can be performed at high speed.

As a result, in the filing apparatus 101 in which image data with high compression efficiency is stored, it is possible to check the filed image data in a short time. Can be realized at low cost.

In the present embodiment, the image processing for generating a reduced image is described using the JPEG method as an example. However, the image processing is not limited to this as long as it is an image compression processing suitable for a multi-valued image.

Further, in the present embodiment, the image processing unit may be configured to generate a plurality of reduced images having different resolutions.

In this case, a quality level parameter of the reduced image to be generated is included in the reduced image creation request from the PC,
An optimal reduced image is selected from a plurality of reduced images based on the quality level parameter, generated, and provided.

[Second Embodiment] FIGS. 5 and 6 show an image processing apparatus, an image processing method, an image processing program according to the present invention and a second example of a recording medium on which a program thereof is recorded.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating an embodiment, which is an embodiment of a filing system using the image processing apparatus, the image processing method, and the image processing program.

In this embodiment, in the image compression processing in the first embodiment, dither processing is performed instead of double image compression processing in which the first image compression processing is performed, and rearrangement is performed based on the dither matrix. It is characterized in that compression processing is performed after processing. Other configurations are the same as those of the first embodiment, and the configurations of the filing system and the filing apparatus of the present embodiment are the same as those of FIGS. 1 and 2. Description is omitted.

First, the principle of the reordering process based on the dither matrix in the image processing unit 206 of this embodiment will be described with reference to FIG.

FIG. 5A shows only one row of a dither matrix (16 × n) representing 256 gradations for the sake of simplicity. FIG. 5B shows a corresponding rearrangement matrix.

In a binary image using a dither matrix to express a gradation image, the probability that the pixel corresponding to each position of the dither matrix becomes 1 corresponds to each numerical value on the dither matrix. Therefore, in this rearrangement process, the pixels are rearranged so as to be arranged from the left side in the descending order of the probability that each pixel is 1, and the pixels whose pixels are “1” are grouped on the left side and the pixels whose pixels are “0” Are easily grouped on the right side.

In the rearrangement process, the data is uniquely determined from the dither matrix.
Is shown in FIG. 5 (b).

Each number in the rearrangement matrix indicates to which pixel position each pixel should be moved based on the accuracy of 1 obtained from the number in the dither matrix shown in FIG. 5A. "14" means that within the block of adapted pixels of this matrix,
“0”, which moves to the first pixel position, means to move to the first pixel position from the left.

When the density of 128 in 256 gradations is expressed by using this dither matrix, pixels are arranged in the line of interest as shown in FIG.
The arrangement as shown in FIG. 6B is obtained by the rearrangement matrix.

As described above, the pixels whose pixels are “1” are grouped on the left side by the rearrangement process, and the pixels whose pixels are “0” are easily grouped on the right side. Compared with the run length of the data, the run length of the image data, that is, the length in which “1” or “0” continues is longer, so that efficient compression processing can be performed.

FIG. 7 shows the image data of the present embodiment before and after the rearrangement process when the image data is divided into pixel blocks of N pixels × M pixels (8 pixels × 8 pixels in the figure). FIG. Each arrow indicates to which pixel block each pixel after rearrangement belongs before the rearrangement process.

Which pixel block each pixel belongs to before the rearrangement process is determined by, for example, the following matrix obtained from the rearrangement matrix. [0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
0, 1, 0, 1] However, each number in this matrix indicates which 8 × 8 pixel block the pixels corresponding to the matrix belong to before the rearrangement.

The image compression processing after the rearrangement processing is as follows.
As in the second image compression processing of the first embodiment, for example, M
The encoding is performed by the H encoding method or the MR encoding method.

Note that this compression processing is not limited to the MH coding method and the MR coding method.

Next, the principle of generating a reduced image in the CPU 211 of this embodiment will be described.

In the present embodiment, the image data after the above-described rearrangement processing is converted into a pixel block of N pixels × M pixels (for example,
The image is divided into (8 pixels × 8 pixels) and a reduced image is generated based on the data of each pixel block. For example, the number of pixels of each pixel block to which each pixel belongs in the rearranged data is counted and the number of pixels is counted for each pixel block for every predetermined line (8 lines) of data in the JPEG method in all image data. The average pixel value of the pixel block is calculated as shown in (Equation 2) based on the number of pixels and the total number of pixels constituting the pixel block. Average pixel value of pixel block = (Number of counted pixels × 255) / Total number of pixels of pixel block (Equation 2)

Therefore, the average pixel value of the pixel block calculated in this way is set to the pixel value of the pixel block, and the reduced image is generated by calculating the average pixel value of all the pixel blocks. .

In the present embodiment, a reduced image is generated by a program, but hardware means for generating a reduced image may be used. Further, it has means for detecting whether such hardware means is connected to the filing apparatus 101, and when the hardware means is connected, generates a reduced image by the hardware means, When the hardware means is not connected, it may be created by a program stored in the HDD 203.

Next, the reduction processing operation of this embodiment will be described with reference to FIG.

FIG. 8 is a flowchart showing a reduced image creation processing operation. It is also assumed that a plurality of compressed image data have already been stored in the HDD 203 and have been filed. The image processing in the generation of the reduced image is performed by the JPEG method. Further, this operation is repeatedly performed in parallel with the main routine in the operation of the filing apparatus 101.

First, the HDD 211 is sent to the CPU 211 by the PC 102.
When a request to create a reduced image of any image data stored in the storage unit 3 is confirmed (step S21), the CPU 21
1 reads out the compressed image data from the HDD 203 (step S22), performs decompression processing corresponding to the image compression processing (step S23), and writes the reordered image data to the RAM 204 (decompression processing). Step (Step S24)).

Next, the image data is divided into predetermined pixel blocks, and a memory area for counting the average pixel value of each pixel block is cleared (division step (step S25)). The following operation is performed for every predetermined line of image data (lines constituting each pixel block), for example, for every eight lines (calculation step).

First, it is determined which pixel block the corresponding pixel bit of the image data belongs to (step S2).
6) Then, the number of pixels of each corresponding pixel block is calculated (step S27). For example, if the pixel value of the pixel bit is “1”, the number of pixels of the pixel block to which the pixel belongs is added.

Next, it is determined whether or not each bit processing for all the pixels constituting the pixel block and the addition processing have been completed (step S28). If not completed, the flow proceeds to step S26. The number of pixels in the pixel block is calculated. When it is determined that the bit processing has been completed and the addition processing has been completed, the calculation of (Equation 2) is performed to calculate the average pixel value of each pixel block (step S29), and the average pixel value of each pixel block is calculated. The values are written to the RAM 204 (step S30).

Next, it is determined whether or not data (8 lines) for a predetermined line capable of performing JPEG processing has been prepared (step S31).
The process goes to step 25 to read the lines constituting each pixel block in the next image data, and calculate the average pixel value of each pixel block. If it is determined that the data for a predetermined line has been collected, JPEG compression processing is performed (step S32).

Next, the compressed data obtained by the JPEG compression processing is written to the RAM 204 (step S3).
3) It is determined whether or not the pixel block whose average pixel value has been calculated in steps S5, S6, and S7 is the last pixel block in the image data (step S34). If it is not the last block, the process goes to step S25 to process the next pixel block. In the case of the last pixel block, JPEG-compressed image data is output to the HDD 203 (step S35), and the process returns to step S21.

In the present embodiment, the reduced image is generated in this manner. For example, the reduced image output to the HDD 203 is instructed by the CPU 211 to the PC 102 to which the HDD 203 has requested the creation of the reduced image. Is provided. Therefore, the PC 102 that has been requested to create a reduced image can display the reduced image on the display device.

As described above, according to the present embodiment, it is possible to decompress the image data that has been subjected to the image compression processing by the reduced image generation processing, and divide the decompressed image data into predetermined blocks. Can be
It is also possible to detect each pixel belonging to each pixel block in the decompressed image data and calculate an average pixel value of each pixel block based on the detected number of pixels for each pixel block. it can.

Therefore, if image data is subjected to dither processing by the image processing unit 206 and the dither-processed image data is subjected to compression processing based on rearrangement processing for each pixel value, this compression processing A reduced image can be generated based on the data that has been decompressed and rearranged, so when generating a reduced image from compressed image data, the pixel values need not be rearranged. Thus, the reduced image generation processing can be performed at high speed.

As a result, in the filing apparatus 101 in which image data with high compression efficiency is stored, it is possible to check filed image data in a short time. Can be realized at low cost.

As in the first embodiment, in this embodiment, the image processing for generating the reduced image is performed by JPEG.
Although the method has been described as an example, the present invention is not limited to this as long as it is an image compression process suitable for a multi-valued image.

In the present embodiment, the image processing unit may be configured to generate a plurality of reduced images having different resolutions.

In this case, a parameter of the quality level of the reduced image to be generated is included in the reduced image creation request from the PC,
An optimal reduced image is selected from a plurality of reduced images based on the quality level parameter, generated, and provided.

[0117]

According to the present invention, an image processing apparatus, an image processing method,
An image processing program and a recording medium on which the program is recorded are obtained by dividing image data subjected to multiplex compression processing into predetermined pixel blocks,
If compression processing is performed by calculating and processing a representative pixel value based on a ratio of pixels having a predetermined pixel value for each pixel block, by obtaining data holding a state in which this processing has been performed, Since a reduced image can be generated, there is no need to perform decompression processing in all compression processing when generating a reduced image from multiplexly compressed image data, and the reduced image generation processing can be performed at high speed. Thus, the image processing apparatus can be realized at low cost.

If the image data is binarized and the binarized image data is subjected to a compression process based on a rearrangement process for each pixel value, the compressed data Can be reduced to generate a reduced image based on the data that has been subjected to the rearrangement processing. Therefore, when a reduced image is generated from compressed image data, the reduced image can be reduced without rearranging the pixel values. Image generation processing can be performed at high speed, and an image processing apparatus can be realized at low cost.

If the representative pixel value of each pixel block has gradation information and the average pixel value of each block calculated by the calculation means includes gradation information, the reduced image generation means Since the gradation information can be reflected on the generated reduced image, the reduced image generation processing can be performed at high speed, and the reproducibility of the compressed original image data can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing first and second embodiments of an image processing apparatus, an image processing method, an image processing program, and a recording medium on which a program thereof is recorded according to the present invention. 1 is a block diagram showing a configuration of a filing system using an image processing program.

FIG. 2 is a block diagram illustrating a configuration of a filing apparatus according to the first and second embodiments.

FIG. 3 is an example showing a configuration of first compressed image data according to the first embodiment.

FIG. 4 is a flowchart illustrating a reduced image generation operation according to the first embodiment.

FIGS. 5A and 5B are a part of a matrix in a rearrangement process according to a second embodiment, where FIG. 5A is an example of a dither matrix and FIG. 5B is an example of a rearrangement matrix.

FIGS. 6A and 6B are examples of pixel data for explaining a rearrangement process according to the second embodiment, wherein FIG. 6A illustrates pixel data before rearrangement, and FIG. 6B illustrates pixel data after rearrangement.

FIG. 7 is an example of a pixel block for explaining a rearrangement process according to a second embodiment, where (a) shows pixel data before rearrangement in the pixel block, and (b) shows pixel data after rearrangement in the pixel block. Pixel data.

FIG. 8 is a flowchart illustrating a reduced image generation operation according to the second embodiment.

FIG. 9 is a block diagram illustrating a configuration of a conventional image processing apparatus that generates a reduced image.

FIG. 10 is another block diagram illustrating a configuration of a conventional image processing apparatus that generates a reduced image.

[Explanation of symbols]

100 Filing System 101 Filing Device (Image Processing Device) 102 PC 103 LAN 201 Scanner 202 Plotter 203 HDD (Recording Medium) 204 RAM 205 ROM 206 Image Processing Unit (Binarization Processing Means, Rearrangement Means) 207 Operation Panel 208 NIC 209 Modem 210 NCU 211 CPU (acquisition means, calculation means, reduced image generation means, decompression processing means, division means) Steps S3, S4 Acquisition step S6, S7 Calculation step S9, S10, S11, S12 Reduced image generation step S23, S24 Decompression process step S25 Dividing process Steps S26, S27, S28, S29, S30 Calculation process Steps S32, S33, S34, S35 Reduced image generation process

Claims (9)

[Claims] An image compression process for image data that has undergone multiple image compression processes divides the image data into predetermined pixel blocks, and includes a pixel having a predetermined pixel value for each of the pixel blocks. An image processing apparatus that calculates a representative pixel value based on a ratio of the image compression processing, and generates a reduced image of the multiplexed image compression-processed image data. Acquiring means for acquiring data in which the representative pixel value for each pixel block is calculated in one process, and based on the representative pixel value and the number of pixels having the predetermined pixel value in each pixel block acquired by the acquiring means Calculating means for calculating an average pixel value of each of the pixel blocks by using the calculating means; An image processing apparatus comprising: a reduced image generation unit configured to generate the reduced image based on a pixel value. 2. Binarization processing means for binarizing image data, rearrangement processing means for rearranging the image data binarized by said binarization processing for each pixel value, An image processing apparatus for generating a reduced image of the image data subjected to the image compression processing by a compression processing means for compressing the data rearranged by the conversion means; Decompression processing means for performing the following processing; division means for dividing the sorted binary data into predetermined pixel blocks; detecting each pixel belonging to each pixel block divided by the division means, Calculating means for calculating an average pixel value of each pixel block based on the calculated number of pixels for each pixel block; Image processing apparatus characterized by comprising a reduced image generation means for generating the reduced image based on the average pixel value of each pixel block. 3. The image processing apparatus according to claim 1, wherein said reduced image generating means generates a reduced image having gradation information. 4. An image compression process for image data that has been subjected to multiple image compression processes, the image data is divided into predetermined pixel blocks, and a pixel having a predetermined pixel value for each pixel block. A computer which generates a reduced image of the multiplexed image compression-processed image data by performing a decompression process by performing a decompression process. Acquiring means for acquiring data in which a representative pixel value is calculated for each pixel block; each of the pixel blocks based on the representative pixel value and the number of pixels having the predetermined pixel value in each of the pixel blocks acquired by the acquiring means Calculating means for calculating an average pixel value of each pixel block based on the average pixel value of each pixel block calculated by the calculating means. An image processing program for causing the image processing apparatus to function as reduced image generation means for generating the reduced image. 5. A method for binarizing image data, rearranging the binarized image data for each pixel value,
A decompression processing unit that performs a decompression process corresponding to the image compression process of the compression processing unit by generating a reduced image of the image data that has been subjected to the image compression process by compressing the rearranged data; Dividing means for dividing the processed binary data into predetermined pixel blocks; detecting each pixel belonging to each of the pixel blocks divided by the dividing means; and calculating the number of pixels for each of the detected pixel blocks. Calculating means for calculating an average pixel value of each of the pixel blocks based on the average pixel value of each pixel block calculated by the calculating means. Image processing program. 6. An image compression process for image data which has been subjected to multiple image compression processes, the image data is divided into predetermined pixel blocks, and a pixel having a predetermined pixel value for each pixel block. A representative pixel value is calculated based on the ratio of the image data, and an image processing program for generating a reduced image of the image data subjected to the multiple image compression processing by the computer is recorded. Acquiring means for acquiring data in which a representative pixel value for each pixel block in one of the image compression processes is calculated by the representative pixel value and the predetermined pixel value in each of the pixel blocks acquired by the acquiring means Calculating means for calculating an average pixel value of each of the pixel blocks based on the number of pixels having A computer-readable recording medium having recorded thereon an image processing program for functioning as reduced image generation means for generating the reduced image based on the calculated average pixel value of each pixel block. 7. The image processing apparatus according to claim 1, wherein the computer performs binarization processing on the image data, rearranges the binarized image data for each pixel value, and compresses the rearranged data. A recording medium storing an image processing program for generating a reduced image in the compressed image data, comprising: an expansion processing means for performing expansion processing corresponding to the compression processing; A dividing unit that divides each pixel block into a plurality of pixel blocks; detecting each pixel belonging to each pixel block divided by the dividing unit; and an average pixel value of each pixel block based on the detected number of pixels of each pixel block. Calculating means for calculating the reduced image based on an average pixel value of each pixel block calculated by the calculating means. A computer-readable recording medium having recorded thereon an image processing program for functioning as a reduced image generating means. 8. An image compression process for image data which has been subjected to multiple image compression processes, the image data is divided into predetermined pixel blocks, and a pixel having a predetermined pixel value for each of the pixel blocks. An image processing method for calculating a representative pixel value based on a ratio of the image compression processing, and generating a reduced image in the multiplexed image compression-processed image data. An acquisition step of acquiring data in which the representative pixel value for each pixel block is calculated in one process, and based on the representative pixel value and the number of pixels having the predetermined pixel value in each pixel block acquired in the acquisition step Calculating an average pixel value of each pixel block by using A reduced image generating step of generating the reduced image based on the prime value. 9. Binarizing image data, rearranging the binarized image data for each pixel value,
An image processing method for generating a reduced image of the image data that has been subjected to the image compression processing by compressing the rearranged data, comprising: an expansion processing step of performing expansion processing corresponding to the compression processing; A dividing step of dividing the processed binary data into predetermined pixel blocks; detecting each pixel belonging to each pixel block divided by the dividing step; and detecting the number of pixels for each detected pixel block And a reduced image generation step of generating the reduced image based on the average pixel value of each pixel block calculated by the calculation unit. Characteristic image processing method.