JPS61216574A - Compression encoding system of picture information - Google Patents

Abstract

PURPOSE:To constitute the titled system so as to inform to a processor means when a compression reproducing means completes a processing of a data and improve a performance of an entire system by transferring a picture data of an amount near to a prescribed accumulating capacity as an unit to an accumulating means by the processor means. CONSTITUTION:A picture data of continuous N lines of the picture information is fed in a lump to a compression reproducing section 32. In the compression reproducing section 32, this is received as an unit, successively compression encoded and accumulated in a picture information memory 36. A section corresponding to the N lines in the accumulated data is read as the unit by the compression reproducing section 32 and encoded and reproduced. This processing is completed and then, it is informed to a CPU 10. This value N, considering an accumulating capacity of an input line buffer 100 of the compression reproducing section 32, is set to a value in which the N line picture data can be accumulated therein.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a compression encoding system, and particularly to a compression encoding system that compresses and encodes image information such as a facsimile in one dimension.

Conventional technology One-dimensional compression group coding methods for image information, such as the Modified Huffman (MH) coding method, are useful for transmitting image data in image information communication systems and storing image information in memory. Used effectively to improve efficiency or storage efficiency.

Such redundancy compression and reproduction of image information has generally been performed by an image information compression/reproduction device commonly connected to a central processing system (CPU) along with other devices via a system bus. Such an image information compression/reproduction device is
It occupied the position of a slave unit with respect to the system bus, and was under the control of the CPU, transmitting and receiving control signals and transferring data.

Generally, many units other than this compression/reproduction device are connected to the system bus. Therefore, in order to improve the overall performance of the system so that it can handle a larger amount of image information at high speed, it is necessary to use the system bus more efficiently by shortening the processing time of each unit connected to the system bus. Ru.

In the conventional system, for example, image information forming a main scanning line (line) is taken into a compression/reproduction device line by line using a rask scanning method, and redundancy compression or reproduction processing is performed. In this type of system, even if the image data is short, that is, the number of dots per line is small and the storage capacity of the line data buffer provided in the compression/reproduction device has sufficient storage capacity, the input of the image data to the compression/reproduction device is possible. Each time there is an output, the CPU has to frequently activate the system bus to perform processing. Therefore, the throughput of the CPU with respect to other units connected to the same bus was relatively reduced.

Purpose The present invention aims to eliminate the drawbacks of such conventional techniques and provide an image information compression encoding system that improves the performance of the entire system, for example, by being able to process a larger amount of image information at high speed. .

Structure In order to achieve the above object, the present invention provides an image information compression encoding system that performs one-dimensional compression group encoding on image data formed by rask scanning of a document image, and encodes and reproduces the compressed and encoded image data. The compression encoding system includes a processing device means and a compression/reproduction means connected to and controlled by the processing device means, the compression/reproduction means having a predetermined storage capacity and for storing image data. a storage means; and a compression and reproduction processing means for one-dimensional compression group encoding of the image data of the rask scan stored in the storage means and code reproduction of the compression-encoded image data stored in the storage means; The device means transfers an amount of image data substantially equal to or close to a predetermined storage capacity to the storage means, and the compression and reproduction processing means transfers image data stored in the storage means to the storage means. This system is characterized by an image information compression encoding system that notifies the processing device means of this information. The details will be explained below based on one embodiment of the present invention.

Referring to FIG. 1, an embodiment of the image information compression encoding system according to the present invention is realized as a data processing system that can also handle image data as one of various data. This data processing system is a central processing unit (CPU)
The system bus 12 connected to and controlled by the to, includes a program memory 14, a data memory IB, an image input interface 18, a display control section 22, a communication interface 2B, an image information compression/reproduction section 32, an image processing section, and other components. unit 34, and image information memory 36
is connected.

CPU TO is a control device that supervises and controls the entire water system according to the program stored in the program memory 14, and the data necessary for the control is stored in the data memory 1.
It is stored in B. An input device 38 such as a keyboard is connected to the CPU 10.

An image scanner 20 is connected to the image input interface 18, and the scanner 20 is an image information input device that optically scans a visible image of a document to obtain a corresponding image information signal. This image information signal is D (natural number) forming a horizontal scanning line, that is, a main scanning line (line).
It is output in the form of dot data consisting of pixels.

An image display device 24 such as a CRT is connected to the display control section 22, and displays image information input by the scanner 20, data input from the input device 38, commands and data instructed by the operator from the CPU 10, etc. is visible here.

A communication line 28 such as a facsimile line, a communication line 30 to another data processing system, and the like are connected to the communication interface 28, thereby allowing the present apparatus to transmit image information with other systems.

In this embodiment, the image information compression/reproduction unit 32 encodes the image information portion based on the Rusk scanning method among various data input to the system using a one-dimensional compression grouping system such as the MH method, Also.

It has a function of encoding and reproducing image data compressed and encoded in this manner to recover the original image information. The image information data compressed and encoded in this manner is efficiently transmitted to one communication line 28 or 30 and efficiently stored in the image information memory 36. Details of the configuration will be explained later with reference to FIG.

These image information are temporarily stored in a buffer area formed in a part of the data memory 1B, and are finally stored in the image information memory 3B. Tapes and the like are advantageously applied.

Referring to FIG. 2, the configuration of the compression/reproduction section 32 is shown in relatively detail. The compression/reproduction unit 32 has an input line buffer 100 . Compression and reproduction processing section 102. Output line buffer 104. and a unit control section 10B.

Input line buffer 100 and output line buffer 1
04 are line data buffers that temporarily store unencoded image information dot data based on the rask scanning method or compressed and encoded image information data, and are connected to the cheetah line 110 of the system bus 12. There is. Advantageously, their storage capacities are each arranged over a number of dots forming a line of the largest document handled by the tree system. For example, it has a capacity that can store dots forming one line when the longitudinal direction of an A3 size image is taken as the main scanning direction.

The compression/reproduction processing unit IQ2 encodes the image information received by the manual line buffer 100 using a one-dimensional compression grouping system such as the MH method in this embodiment, and outputs this encoded data to the output line buffer 104. It also encodes and reproduces the compressed and encoded image data received in the input line buffer 1flO to recover the original image information, and outputs this to the output line buffer 104.

The unit control section 10B includes data lines 110 . This is a control device that is connected to the address line 112 and the control line 114 and controls each part of the compression/reproduction section 32 in response to data, addresses, and control signals received therefrom. The data line 110 is a bus for transferring data such as image information, the address line 112 is a line for transferring device addresses, register addresses, storage location addresses, etc. of various units including the compression/reproduction section 32, and the control line 114 is a bus for transferring data such as image information. is the interrupt signal (
IN? ) is a line that transfers various control signals such as

According to the Bokuto method, image data is transferred to the manual line buffer 100 in units of image data in an amount that is substantially equal to or close to the storage capacity of the input line buffer 100, and the compression reproduction processing unit 102 transfers the image data to the manual line buffer 100. When the compression reproduction process for the image data accumulated in the buffer 100 is completed, the CPU 10 is notified to that effect.

For example, as shown in FIG. 4, the inheritance of image information (image data of N (natural numbers such as 2) tree lines is sent all at once to the compression/reproduction section 32, and the compression/reproduction section 32 processes the lines of these N trees. The data is taken as a unit and sequentially compressed and encoded. The encoded data is stored in memory 38. Further, the compression-encoded data stored in the memory 3B is read out to the compression/reproduction unit 32 in units of N lines, and is sequentially encoded and reproduced here. Therefore, the code-regenerated image information forms N lines of image data. In this method, image information is managed in units of N lines within the system. This value N is
Considering the storage capacity of the input line buffer 100, the value is set to a value that allows N lines of image data to be stored therein.

Alternatively, instead of managing N lines in units of data forming N lines, the number of unencoded image information data corresponding to the storage capacity of the human-powered line buffer 100 may be collectively managed. The image information data is taken into the compression and playback unit 32, and the compression and playback unit 32 sequentially compresses and encodes it, and also takes the encoded image information data into the compression and playback unit 32 in units of dots corresponding to the storage capacity of the buffer 100. The latter method, which may be configured to perform code reproduction sequentially, does not use line management to handle image data line by line;
The edge of the line frame is excluded in the processing of image data within the system.

As can be seen from FIG. 3, which shows the operational flow of the compression/reproduction processing unit program executed by the CPU 10 to control the compression/reproduction unit 32 and stored in the program memory 14, the CPU 10 first performs the above-mentioned operations. Setting the processing mode for data processing (200), scanner 20
From then on, document image information data of n dots per line is sequentially input to the system.

In this embodiment, this image data is transferred to the compression/reproduction unit 32 for transmission or storage in units of 8547 minutes.
CPU TO then sets the number of transfer data to N lines in this example (202).

Therefore, the CPU to compresses and reproduces this image data in units of 8547 minutes for transmission or storage.
(204), which is taken from data line 11G to input line buffer 100. When the transfer is completed, the CPU 10 becomes idle waiting for an interrupt (INT) from the compression/reproduction unit 32.
(20B), t Therefore, the CPU to can execute other jobs until an interrupt occurs.

When 8547 worth of data is accumulated in buffer 100,
In the compression/reproduction unit 32, under the control of the unit control unit 108, the compression/reproduction processing unit 1G2 sequentially reads out image information data from the input line buffer 10G and converts it into one-dimensional compressed group encoding.

Compression encoded data is sequentially output to the line buffer 10
It is stored in 4. When the compression-encoded data corresponding to the N lines is stored in the buffer 104, the unit control unit 106 sends an interrupt flag (I) to the control line 114.
NT).

When the interrupt flag is set, the CPo 10 responds by interrupting other tasks at an appropriate point if they are currently being executed, and checks the logic of the processing results of the compressed and encoded image data (210). , if the processing result is correct, GP
tl 10 reads encoded data from the output line buffer 104 (212) and stores it in the image information memory 36.
If the 0-image information data stored in 1 or transmitted to the outside via the communication interface 2B is not the last page of the page in which it is included (214), the above operations are repeated until the end of the page is reached. .

In this embodiment, the completion of processing in the compression/reproduction unit 32 was configured to be notified to the CPo 10 by an interrupt, but instead of an interrupt, a status register is provided, and this register is used to notify the end of the compression or reproduction processing. Set and CPo 1
It may be configured to notify G.

When the image data compressed and encoded in this manner is encoded and reproduced, the compression and reproduction section 32 operates in the same manner. In this case, encoded image data is transferred to the input line buffer 100 as described above, and this is transferred to the compression and reproduction processing section 1.
02 and output line buffer 104.
Basically, the operation flow shown in FIG. 3 is applied as is, with the only difference being that it is stored in the .

Further, when data is not handled in such an N-line management format, image information data corresponding to the storage capacity of the input line buffer 100 is taken into the compression/reproduction unit 32 as a unit and compression encoding and code reproduction are performed. Also, the compression/reproduction section 32 operates in the same manner.

In this case, as described above, an amount of image data substantially equal to or close to the storage capacity of the input line buffer 100 is transferred to the input line buffer 100, and this is transferred to the compression and reproduction processing section 100.
The data is compression-encoded or code-regenerated and stored in the output line buffer 104. Basically, the content of the mode setting in step 200 and the content of the mode setting in step 202
The operation flow shown in FIG. 3 can be applied as is, except that the contents of the number of data to be transferred in are slightly different from the above-mentioned example.

By the way, in conventional methods, when document image information in which image data of n dots per line is formed for m lines is input from an input device such as a scanner, the system processes it line by line. In general, the image information compression/reproduction device used in , has a line buffer that can store image data for one line, and in this example, the image data is processed m times in units of lines.

The storage capacity of a line buffer is generally configured to approximate the number of dots forming one line of the largest document handled by the system. Therefore, in the case of image information of a small document, only a portion of the storage capacity of the line buffer is stored, so although the amount of image data transferred at one time is small, the number of transfers per unit time is , and therefore the frequency of compression/reproduction processing increases. Since many other slave units are connected to the system bus to which the compression/reproduction device is connected, the throughput of the processing device with respect to these other units is reduced accordingly.

However, according to the embodiment of the present invention described above, whether compressing and reproducing is performed in units of image data for N trees of lines, or compressing and reproducing in units of data corresponding to the storage capacity of the line buffer, The number of data units processed by the compression/reproduction unit 32, ie, the number of virtual lines, is decreasing. Therefore, the frequency with which the CPo 10 executes the flow shown in Figure 7J3 is reduced compared to the conventional method.

In the operation flow shown in FIG. 3, compression processing is started once for each arrow indicated by numerals 130 and 132 in FIG. 4, and reproduction processing is started once for each arrow indicated by numerals 134 and 136. Ru. Conventionally, a compression or regeneration flow is activated for each line individually.

Therefore, in the example shown in Figure 4, 1 of the number of startups in the conventional method
/2. As will be seen, the number of processing steps in which the CPU to the compression/reproduction unit 32 is involved, and thus the processing time thereof, is reduced. This will give you more time to perform other tasks. therefore,
Improves overall system performance.

For example, in the system of this embodiment in which the storage capacity of the input line buffer 100 is set equal to the number of dots in the longitudinal direction of an A3-sized original as described above, when the A4-sized original is main-scanned in its lateral direction, the latter Image data for two lines of a document can be transferred as a unit to the compression/reproducing section 32.

Therefore, the number of lines of image data processed by the CPU 10 is virtually halved compared to the conventional method, and the frequency with which the system program starts the flow shown in FIG. The number of steps is reduced. In other words, the time that the CPt 110 is involved in the compression/reproduction section 32 is reduced, and the performance of the entire system is improved.

As a side effect, if the processing speed of the CPU 10 is sufficiently high compared to the data transfer time, the overall time required to complete processing of one page of image data can be shortened. be.

Class-j According to the present invention, image information is compressed and reproduced in a manner that effectively uses the storage capacity of the line buffer of the image information compression and reproduction section, so a larger amount of image information can be processed at high speed. In addition, processing time for other slave units in the system is freed, and the performance of the entire system is improved. Furthermore, this method can be realized without modifying the configuration of the compression/reproduction unit or the like.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing the configuration of an embodiment in which the image information compression encoding method according to the present invention is applied to a data processing system that can also handle image data as one of various data. A block diagram showing the configuration of the compression/reproduction section shown in FIG. 1 in relatively detail, and FIG. 3 shows an operation flow of the compression/reproduction processing section program executed by the CPU shown in FIG. 1 to control the compression/reproduction section. Flowchart FIG. 4 is an explanatory diagram for explaining the basic principle of the image information compression encoding system according to the present invention.゛Main part: Code theory 101. , CPU 320. . Compression playback section 3B0. . Image information memory 100, , input line buffer +02. ,,compression/reproduction processing unit 104, ,output line buffer toe, ,unit control unit

Claims (1)

[Claims] 1. An image information compression encoding system that one-dimensionally compresses and encodes image data formed by raster scanning of an original image, and encodes and reproduces the compressed and encoded image data, the system comprising: , processing device means, and compression and reproduction means connected to and controlled by the processing device means, the compression and reproduction means having a predetermined storage capacity and a storage capacity for storing image data. comprising a storage means, and a compression reproduction processing means for one-dimensionally compressing and encoding the raster scan image data stored in the storage means and encoding and reproducing the compression-encoded image data stored in the storage means, The processing device means transfers an amount of image data substantially equal to or close to the predetermined storage capacity to the storage means, and the compression reproduction processing means transfers the image data stored in the storage means. 1. A compression encoding system for image information, characterized in that when compression and reproduction processing is completed for an image, the processing device means is notified of this. 2. In the compression encoding system according to claim 1, the processing device means transfers image data corresponding to a plurality of main scanning lines to the storage means in units of inheritance in the document image. Characteristic compression encoding system. 3. The compression encoding system according to claim 1, wherein the processing device means transfers image data in an amount substantially equal to the predetermined storage capacity to the storage means. compression encoding system.