JPH04369972A - Encoding/decoding system - Google Patents

Abstract

PURPOSE:To provide the encoding/decoding system simplifying the exchange of command between a host control part and an encoding/decoding part and realizing the entire information processing using an inexpensive host control part with a small number of parts. CONSTITUTION:The device is provided with at least a data input/output part 41, an encoding/decoding part 40, and a host control part 7 controlling the entire system. The host control part 7 instructs the start of the encoding/ decoding processing to the encoding/decoding part 40 by the request from the data input/output part 41. The encoding/decoding part 40 receives the instructions to perform successive data processing based on the information (information representing a page unit) on the movement amount in the sub scanning direction of the data from the data input/output part 41 without through the host control part 7, and inform the host control part 7 of the end of the data processing.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention improves the signal processing performance of the host controller by simplifying the encoding/decoding method, particularly the sending and receiving of commands between the host controller, the encoder, and the decoder. The present invention relates to an encoding/decoding method suitable for use in a facsimile machine.

0002

[Prior Art] In facsimile, in order to improve the transmission efficiency when transmitting image data, CCITT
As recommended by the International Telegraph and Telephone Advisory Committee (International Telegraph and Telephone Advisory Committee),
The image data is transmitted using MH, MR, and MMR encoding methods. This encoding method is
This is a method of transmitting black and white changing points in image data in correspondence with codes, and when encoding the same number of data bits, when the number of black and white changing points per unit length is large, the data is transmitted by that amount. The processing amount increases, and the data encoding speed decreases as the data processing amount increases. Also,
The same is true when decoding encoded data; if there are many points of change between black and white per unit length in the original data,
It has the property that even if the same number of code bits is decoded, the number of bits of the decoded data will decrease.

[0003] For this reason, recent facsimile machines require encoding and decoding methods that enable high-speed encoding and decoding even when processing data with many black-and-white changes. Means are beginning to be developed, one example of which is disclosed in JP-A-60-194670 or JP-A-62-35780.

However, when looking at not only the encoding and decoding sections but also the entire facsimile system, the host control section, memory section, reading section, recording section, encoding section, and decoding section in the system are as follows: It is clear that an efficient facsimile system cannot be constructed if the transmission and reception of control signals between these peripheral devices and the state of the data bus load are ignored since they operate in a closely related manner.

[0005] Note that one of this type of facsimile systems
For example, electronic technology April 1988 issue pp64-72
and Electronic Technology, August 1990, pp. 67-71, but there is no mention of improving the efficiency of the encoding and decoding sections in this facsimile system.

[0006]

[Problems to be Solved by the Invention] The conventional high-speed encoding and decoding means described above only disclose a means for reducing the number of parts by converting a facsimile system into a gate array. The method of transmitting and receiving control signals between the encoding section, host control section, and reading section, and the method of transmitting and receiving control signals between the decoding section, host control section, and recording section have been improved. However, no consideration is given to achieving high-speed processing with a small number of parts for the facsimile system as a whole.

For this reason, when the above-mentioned high-speed encoding and decoding means is incorporated into a facsimile system, the control load of the encoding and decoding means on the host control section becomes excessive. The high-speed processing performance of the encoding and decoding means cannot be fully utilized unless a processor with high processing capacity is used or a means of increasing the number of processors is added. . In this case, if a conventional processor is used as the host controller, the processing load on the host controller becomes excessive in order to improve the user application service of the facsimile system as a whole. , there were problems such as not being able to respond satisfactorily.

[0008] Also, in the facsimile described above, which represents the prior art of the present invention, the host control unit manages the timing of the start and completion of operations of each unit, so that the data processing speed in the encoding and decoding units is reduced. If an attempt is made to increase the data processing speed, the processing load on the host control section becomes excessive, resulting in a problem that a satisfactory data processing speed cannot be obtained.

[0009] In order to speed up the encoding and decoding means and improve user application services, it is possible to use processors with high processing power or increase the number of processors. However, a problem arises in that the cost increases accordingly.

The present invention was devised to solve the various problems mentioned above all at once, and one purpose thereof is to simplify the exchange of commands between the host control section, the encoding section, and the decoding section. To provide an encoding/decoding method that can process information in the entire system using a small number of components and a low-cost host control unit, thereby achieving high throughput. It is in.

Another object of the present invention is to provide an encoding/decoding method that does not require sending and receiving commands from a host controller in real time.

0012

[Means for Solving the Problems] In order to achieve the above two objects, the present invention provides at least a data input/output section,
It has an encoding/decoding section and a host control section that performs overall control, and the host control section instructs the encoding/decoding section to start encoding/decoding processing in response to a request from the data input/output section. In response to the command, the encoding/decoding unit sequentially performs data processing based on information regarding the amount of data movement in the sub-scanning direction from the data input/output unit without going through the host control unit, and controls the host control. The data processing apparatus includes first means for notifying the data processing section to the end of the data processing.

[0013] Furthermore, in order to achieve the above two objectives,
The present invention includes at least a reading section that reads a document;
an encoding unit that encodes the data read by the reading unit;
and a host control unit that performs overall control over information processing, and upon receiving a document reading request from the reading unit, the host control unit sets an encoding mode and supplies an encoding command to the encoding unit. After that, the encoding section receives a reading start request from the reading section without going through the host control section and performs encoding processing, and further, the encoding section receives a reading start request from the reading section without going through the host control section, and further performs encoding processing from the reading section without going through the host control section. When a page end request is received, the encoding process is ended and an encoding end signal is supplied to the host controller, and the host controller supplies an encoding end command to the reader to start encoding. It is equipped with two means.

Furthermore, in order to achieve the above two objects, the present invention includes at least a decoding section that decodes encoded data input from a receiving section or an encoded data storage section, and a The host control unit includes a recording unit that records the encoded data, and a host control unit that performs overall control over information processing. The recording mode is set and a decoding command is supplied to the decoding unit, and then the decoding unit receives a recording start request from the receiving unit or encoded data storage unit without going through the host control unit. When a page termination request is received from the reception unit or the encoded data storage unit without going through the host control unit, the decoding process is terminated and the host control unit performs the decoding process. The host controller is provided with third means for supplying an end signal, and the host control section supplies a decoding end command to the recording section to perform decoding.

In addition, in the encoding and decoding processes executed by the second means and the third means, the encoding section and the decoding section include a line memory section having a storage capacity for three lines. The line memory unit has a function of preventing encoding of a line in which input of read data has not been completed, a function of preventing recording of data of a decoded line to which data has not yet been input, and , is provided with a fourth means having a function of preventing the restored data from being written again on the restored image data that has not yet been recorded and output.

[0016]

[Operation] According to the first means, in the encoding/decoding process, when the data input/output section requests encoding/decoding of the image data read from the original or the encoded data received from the line, the host control The unit causes the encoding/decoding unit to start encoding/decoding processing. Thereafter, the encoding/decoding unit encodes the data based on information regarding the amount of movement in the sub-scanning direction (information defining a unit page) supplied from the data input/output unit without any intervention from the host control unit. Encoding and decoding are performed sequentially, and when there is a request to end the encoding and decoding from the data input/output unit, the encoding and decoding processing is terminated and an encoding and decoding completion signal is supplied to the host control unit. At this point, the host controller determines the end signal from the encoder/decoder and instructs the next control operation.

[0017] According to the second means, in the encoding process, before starting the encoding process of the data obtained by reading the document, the host control unit generates the code necessary for the encoding process. The encoding command is supplied to the encoding unit to make the encoding unit prepare for encoding processing. Thereafter, the encoding unit independently determines the timing to start the encoding process, and then encodes the data obtained from the document page by page. Further, the encoding unit independently determines the timing to end the encoding process as before, and thereby ends the encoding process and supplies an encoding end signal to the host control unit. At this point, the host controller determines the end signal from the encoder and instructs the next control operation.

Furthermore, according to the third means, in the decoding process, before starting the decoding process of the input encoded data, the host control unit decodes the commands necessary for the decoding process. and prepares the decoding unit for decoding processing. Thereafter, the decoding unit independently determines the timing to start the decoding process, and then decodes the input encoded data page by page. Further, the decoding section independently determines the timing to end the decoding process as before, and thereby ends the decoding process and supplies a recording end signal to the host control section. Even at this point, the host control section judges the end signal from the decoding section and instructs the next control operation.

[0019] Due to the above-described effects, the host control unit does not need to perform real-time control over encoding and/or decoding processing, and the load on the host control unit is significantly reduced. Become. Furthermore, since the time required for the real-time control can also be used for processing other information, it is possible to speed up the encoding and/or decoding processing executed by the host control section.

Furthermore, even if the encoding/decoding process is sped up as described above, the host control unit manages the timing of the start and end of the encoding/decoding process, and Compared to the prior art system in which the host control unit controls the encoding unit and decoding unit in real time, the processing load on the host control unit is actually reduced, so it is possible to use a high-performance processor capable of high-speed processing. and the need for the use of multiple processors is completely eliminated.

In addition, according to the fourth means, the data is stored in a line memory section having a storage capacity of three lines, respectively, when encoding read data of a document or recording data after decoding. Since it is temporarily stored,
Can speed up pipeline processing. In addition, it is possible to prevent the encoding of data for lines to which no data has been input yet, to prevent the output of the data to the recording unit for lines to which decoded data has not yet been input, and to prevent the data from being output to the recording unit for lines to which decoded data has not been input. Since it has a function of preventing restored data from being written again on restored image data that has not been output, there is no need for a control device to properly manage the flow of codes and image data.

[0022] The line memory section is A3
Even if a paper of the same size is read at 400 dpi, it is sufficient to use about 2 kbytes of memory for 3 lines. In order to manage the line memory section at high speed, it is more economical in terms of hardware to incorporate it into the encoding section and decoding section, rather than using its own processor. This allows for simplification.

[0023] By employing each of the above means, the host control unit only intervenes in the encoding unit and decoding unit for each page of the original, and therefore it is not necessary to read data to the encoding unit and to read data to the decoding unit. It becomes possible to realize high-speed recording with high cost performance.

[0024]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a facsimile apparatus to which the encoding/decoding method according to the present invention is applied.

In the figure, 1 is an encoding section, 2 is a decoding section, 3 is an encoding processing section, 4 is a line memory section, 5 is a decoding processing section, 6 is a line memory section, and 7 is a host control section. The constituent microprocessor units (hereinafter referred to as host MPU) include a reading unit 8, a recording unit 9, a communication control unit 10, a code data memory unit 11, a control bus 12 to 21, and a data unit 22 to 29. It's a line. Further, the encoding section 1 and the decoding section 2 constitute an encoding/decoding section 40, and the reading section 8, the recording section 9, the communication control section 10, the encoded data memory section 11, etc. constitute a data input/output section 41. are doing.

The encoding section 1 consists of an encoding processing section 3 and a line memory section 4, and the decoding section 2 consists of a decoding processing section 5 and a line memory section 6. The reading section 8 scans and reads the original, and supplies the read image data to the line memory section 4 of the encoding section 1 via the data line 22. The line memory unit 4 is a memory that has a storage capacity for three lines of the document and is capable of reading at a constant speed of 10 Mb/s or more, and temporarily stores the read image data, It is then read out for encoding and supplied to the encoding processing unit 3 via the data line 23. The line memory section 6 is also a memory that has a storage capacity for three lines of the document and is capable of reading at a constant speed of 10 Mb/s or more, and temporarily stores the image data decoded by the decoding processing section 5. It is then read out for recording and supplied via the data line 27 to the recording section 9 where it is recorded. Further, the reading section 8, the recording section 9, the encoding section 1, and the decoding section 2 are connected to the host MPU 7 via control buses 12 to 17, respectively. and encoding processing unit 3
The decoding processing section 5 and the line memory section 6, and the line memory section 6 and the recording section 9 are connected by control buses 18 to 21 and data lines 22, 23, 26, and 27, respectively. Further, an encoding processing section 3, a decoding processing section 5,
The communication control section 10 and code data memory section 11 are connected to the host MP via data lines 24, 25, 28, and 29, respectively.
It is coupled to U7.

In this case, the communication control section 10 and the code data memory section 11 are not essential in the encoding/decoding method according to the present invention, and, for example, in a filing device, etc., the communication control section 10 and the code data memory section 11 are not essential for the encoding/decoding method according to the present invention. It is.

Here, regarding the operation of the facsimile machine shown in FIG. 1, the processing flow performed by the host MPU shown in FIG.
This will be explained with reference to FIG. 3 and a diagram showing the time course of processing among the system, host MPU, and encoding unit shown in FIG.

[0030] However, in the following explanation, pages as used in the present invention are not only pages that represent physical breaks in the usual sense, but also pages that have been marked in advance or have physical characteristics of paper, etc. This also includes pages consisting of breaks defined by the above. The unit page when scanning a manuscript and printing image data is determined by the amount of movement of the image in the vertical direction (sub-scanning direction). It means the size of the image determined by the amount of paper feed (feeding amount). By the way, as shown in FIG. 9, even if the image is made up of only letters, a photo is inserted between the letters, or a mixture of letters, photos, and pictures, , the amount of movement m1, m2, m in each of the above cases
3 are treated and counted in the same way.

In FIG. 3, first, an original to be read is set in the reading section 8, and when the original reading request signal 50 from the reading section 8 is supplied to the host MPU 7 via the control bus 14, the host MPU 7 An encoding mode setting command 5 is sent to the encoding processing unit 3 of the encoding unit 1 via the control bus 17.
Supply 1. At this time, the encoding unit 1 uses the command 5
1, it enters the encoding preparation state and waits for the reading start request signal 52 from the reading section 8. Next, when the reading start request signal 52 is directly input to the encoding unit 1 through the control bus 18 without going through the host MPU 7, the encoding unit 1 enters the encoding processing state immediately after receiving the reading start request signal 52. , encodes image data obtained by reading a document supplied from the reading section 8 via the data line 22. This encoding processing state continues until the page end request signal 53 is input from the reading section 8 directly to the encoding section 1 through the control bus 18 without going through the host MPU 7. When the encoding unit 1 receives the page end request signal 53, the encoding unit 1 enters an idle state and simultaneously supplies an encoding end signal 54 to the host MPU 7 via the control bus 16. The host MPU 7 sends the encoding end signal 5
4, it confirms the end of encoding, and at the same time supplies a command 55 to the system to perform the control required by the system. Here, the above-mentioned necessary control includes checking for paper jams that may impede normal execution of facsimile operations, and controlling the reading module to move the next document to a predetermined position when the next document is available. - Control of data, etc. falls under this category. Then, when there is a next document, the next document reading request signal 56 is supplied from the reading unit 8 to the host MPU 7, and after that, the above-mentioned process is executed again, and at this time, an instruction to interrupt the process is given. Without it,
The above processing is continued until reading of all documents and encoding of the read data is completed.

[0032] If the page is marked in advance or has a cut defined by the shape characteristics of the paper, etc., the mark or feature is attached to the reading section or separately from the reading section. If the configuration is configured so that the mark or feature is detected by a newly installed processing unit that detects the mark or feature, the location where the detection is performed will be logically recognized as a page break, and from then on, the above-mentioned This allows continuation of similar processing.

FIG. 2 also shows that during the above process, the host M
The processing flow executed by the PU7 is shown.

Normally, in the case of a facsimile, the host MPU 7 not only controls the entire facsimile, that is, controls the reading of an original and the recording of image data;
It also controls image data transmitted via the communication system and processes information in the man-machine I/F section. First, when the host MPU 7 is in a standby state, When there is any control request from the system, the entire system control process is started and executed (step 30). At this time, in order to perform appropriate processing according to the requests from each system, the overall system control process determines the requests from the systems, as shown in the figure, in conjunction with step 30. (Step 3
0'). In this request determination, processes related to document reading and image data recording are individually determined, and other processes are collectively determined as other system request determination processes.

[0035] While the above-mentioned determination is made, the decision to execute or stop reading the original and encoding the read data is made in the following manner. First, it is determined whether or not there is a document in the reading section 8 (step 31), and if the determination is YES, encoding mode setting processing is performed in accordance with the supply of the document reading request signal 50 (step 32). At the same time, the encoding mode setting command 51 is supplied to the encoding section 1 via the control bus 17 to return to the initial standby state, and when the judgment is NO, the encoder immediately returns to the initial standby state. After the command 51 is output, it is determined whether reading of one page of the original in the reading section 8 has been completed (step 33), and if the determination is YES, the system requires confirmation of the end of encoding. control is performed (step 34) and returns to the initial standby state, and if the judgment is NO, the control immediately returns to the initial standby state.

FIG. 5 is a system diagram showing the transmission paths and transmission order of various signals during the series of operations described above. In addition, in the figure, 1 to 2 indicate the transmission order of the signals.

In the figure, when a document is set in the reading unit 8 and the document reading request signal 50 is output from the reading unit 8 to the host MPU 7 via the control bus 14, the host MP
U7 detects this document reading request signal 50. (2) When the above detection is performed, the host MPU 7 supplies the encoding mode setting command 51 to the encoding section 1 via the control bus 17. (2) The encoding unit 1 enters a state of waiting for a reading start request signal 52, and when the reading start request signal 52 is supplied from the reading unit 8 via the control bus 18, it is supplied via the data line 22. Encoding processing of image data obtained by reading the original is started. After starting this encoding process, the encoding unit 1 continues to execute the encoding process in the set encoding mode until the page end request signal 53 is input. (2) When the reading of one page of the original is completed and the page end request signal 53 is supplied from the reading section 8 to the encoding section 1 via the control bus 18, the encoding section 1 stops the encoding process. . ■ At this time, the encoding unit 1
The encoding end signal 54 is sent to the host MP via the control bus 16.
Outputs to U7 and enters the idle state. Thereafter, the process returns to the initial state, and if there is still a document to be read, the operations described above are repeated in the order of (1) to (3).

As explained above, in terms of reading the original and encoding the read image data, the host MPU 7 monitors the application of the original reading request signal 50 supplied from the reading section 8 and reads the original. Read request signal 50
is supplied, as long as the encoding mode setting command 51 is supplied to the encoding unit 1 in order to prepare for encoding, the reading unit 8 Reading of the document and encoding of the read image data are performed independently only between the encoder 1 and the encoder 1, and real-time control of the host MPU 7 is not required during this time. Furthermore, even at the end of the encoding process of the read image data, the host MPU 7
Similarly, the application of the encoding end signal 54 supplied from the reading unit 8 is monitored for each page of the manuscript, and after the reception of the encoding end signal 54 is detected, other information processing controls can be executed as appropriate. It is something.

Next, operations during decoding of encoded data and recording of decoded image data will be explained using FIGS. 1, 2, and 4.

First, when there is encoded data of a document to be recorded in the recording section 9 in the communication control section 10 or the code data memory section 11, the document is stored in the communication control section 10 or the code data memory section 11. The recording request signal 60 is sent to the host MPU 7
, the host MPU 7 supplies the recording mode setting command 67 to the recording unit 9 via the control bus 13, and also supplies the decoding processing unit 5 of the decoding unit 2 via the control bus 17. A mode setting command 61 is supplied. At this time, the recording unit 9 enters a recording preparation state by supplying the command 67, and the decoding unit 2
1 enters a decoding preparation state, and then enters a state of waiting for a recording start request signal 62 supplied from the recording section 9. At this time, the recording start request signal 62 is sent to the host MP.
When the signal is directly input from the recording unit 9 to the decoding unit 2 via the control bus 21 without going through U7, the decoding unit 2 enters the decoding processing state immediately after receiving the recording start request signal 62.
Data is sent from the communication control section 10 or code data memory section 11.
The encoded data supplied via the data line 25 is decoded. This decoding processing state continues until the page end request signal 63 is input from the communication control section 10 or code data memory section 11 to the decoding section 3 via the host MPU 7. When the decoding section 2 receives the page end request signal 63, the decoding section 2 enters an idle state and supplies a decoding end signal 64 to the host MPU 7 via the control bus 16. When the host MPU 7 receives the decoding completion signal 64, it confirms the completion of the decoding, and also supplies a command 65 to the system to perform the control required by the system.

[0041] Here again, the necessary control includes checking for the presence or absence of paper jams that may impede the normal execution of facsimile operations, and checking the recording of encoded data of a document that is to be further recorded next time. This includes controlling the recording motor and the like for preparation. Then, when there is encoded data of the original to be recorded next, the next original recording request signal 66 is supplied from the communication control section 10 or the encoded data memory section 11 to the host MPU 7, and from then on, the above-mentioned processing is performed. is executed again, and if there is no instruction to interrupt the process at this time, the process will continue to be executed until the encoded data of all the originals to be recorded is exhausted.

Furthermore, FIG. 2 also shows the processing flow executed by the host MPU 7 during the above processing.

This processing flow is almost the same as the processing flow for reading a document and encoding the read data. First, when the host MPU 7 is in a standby state, the host MPU 7 When there is a control request of some kind, the entire system control process is started and executed (step 3).
0), then determines the request from the system (
Step 30'). At this time as well, the decision as to whether to execute or stop decoding the encoded data and recording the decoded data is made in the following manner. First, it is determined whether there is encoded data to be recorded (step 35).
If the determination is YES, the decoding mode setting process is performed in response to the supply of the document recording request signal 60 (step 36), and the decoding unit 3 is connected via the control bus 17.
A decoding mode setting command 61 is supplied to the decoding mode setting command 61 to return to the initial standby state, and when the judgment is NO, the CPU immediately returns to the initial standby state. After the command 61 is output, it is determined whether recording of one page of the document has been completed in the recording unit 9 (step 37), and if the determination is YES, the system needs to confirm the completion of decoding. Control is performed (step 38) to return to the initial standby state, and when the judgment is NO, the control immediately returns to the initial standby state.

FIG. 6 is a system diagram showing the transmission paths and transmission order of various signals during the series of operations described above. Note that in the figure, ① to ② indicate the transmission order of the signals.

In FIG.
When a document recording request signal 60 is output from the communication control section 10 or code data memory section 11 to the host MPU 7, the host MPU 7 receives the document recording request signal 60.
Detection is performed. ■When the above detection is performed, the host MPU 7
supplies a decoding mode setting command 61 to the decoding section 2 via the control bus 17, and at the same time supplies a recording mode setting command 67 to the recording section 9 via the control bus 13. (2) The decoding unit 2 enters a state of waiting for a recording start request signal 62, and when the recording start request signal 62 is supplied from the recording unit 9 via the control bus 21, it is supplied via the data line 25. The decoding process of the encoded data is started. After starting this decoding process, the decoding section 2 continues to execute the decoding process in the set decoding mode until the page end request signal 63 is input. (3) When the transmission of encoded data for one page of the original is completed, a page end request signal 63 is sent from the communication control section 10 or the encoded data memory section 11.
is supplied to the host MPU 7 and further from the host MPU to the decoding unit 2 via the control bus 17, the decoding unit 2
stops the decoding process. (2) At this time, the decoding section 2 outputs a decoding end signal 64 to the host MPU 7 and the recording section 9 via the control bus 16, and enters an idle state. After that, the state returns to the initial state, and from now on, if there is still encoded data of the original to be recorded,
The above operations are repeated in this order.

As explained above, in terms of decoding encoded data and recording the decoded data, the host MPU 7 receives the original data supplied from the communication control section 10 or the encoded data memory section 11. The application of the recording request signal 60 is monitored, and when the document recording request signal 60 is supplied, a decoding mode setting command 61 and recording are sent to the decoding section 2 and recording section 9 to prepare for decoding. As long as the recording mode setting command 67 is supplied for preparation,
Thereafter, the decoding of the encoded data and the recording of the decoded data are performed independently between the decoding section 2 and the recording section 9 without the intervention of the host MPU 7.
During this time, real-time control of the host MPU 7 is not required. Furthermore, even at the end of decoding of encoded data and recording of decoded data, the host MPU 7
As before, monitors the application of the decoding end signal 64 supplied from the communication control section 10 or code data memory section 11 for each page of the document, and detects the decoding end signal 6.
After the reception of No. 4 is detected, control of other information processing can be executed as appropriate.

Next, referring to FIG. 7, a method of transmitting and receiving control signals between the encoding section 1 and the reading section 8 and between the line memory 4 and the encoding processing section 3 will be explained.

In the figure, 100 is a data bus interface.
interface (I/F), 101 is 3 line address control I
/F, 102 is a reading control I/F, and 103 is an encoding operation section, which are connected in a chain to form an encoding processing section 3.
It consists of

The reading control I/F 102 has a function of detecting a page start signal and a page end signal among the control signals sent and received via the control bus 18, and uses this function to detect a page start signal and a page end signal. Detects the page start signal and page end signal,
The data input/output built into the reading control I/F 102 determines the reading start and reading end timing for each page of the original without any other control. The timing signal is controlled to read the original and encode the read data. Also,
3-line address control I/F101 and data bus I/F101
F100 controls the exchange of image data between the line memory section 4 and the encoding processing section 3 as described below.

Generally, when encoding image data, the greater the number of changing points of black and white pixels per unit length in the image data, the longer it takes to encode the image data. It takes. Normally, when reading image data, the image data is read at a constant speed. If no memory means is disposed between the encoder 1 and the encoder 1, the read data must be encoded in synchronization with the read of the image data at a constant speed. on the other hand,
When encoding image data at a constant speed, in order to prevent unencoded image data signals from being generated when encoding is delayed, encoding is usually done in anticipation of its safety. The input speed of image data input to section 1 is suppressed.

By the way, even when a memory means is arranged between the reading section 8 and the encoding section 1, when the encoding speed of image data is set to be relatively fast, the image data still remains. Since there is a risk that encoding will be executed to a line for which data reading has not been completed, a function is provided to prevent the line being encoded from overtaking the image data input line of the memory means. The need arises to add .

In this case, in order to encode the image data at high speed, the image data is stored in the RAM for each page of the original.
If the data is stored in a memory such as , and then encoded after the storage is completed, there is no need to make settings that take into account the safety of the encoding time, and speed-up can be expected, but a huge amount of bitmap page memory is required. Moreover, the memory management function also becomes large, making it extremely uneconomical.

The present invention adopts a configuration capable of dealing with such a case, and by incorporating the above function into the encoding processing section 4, it is possible to avoid increasing the processing load on the external control element. It can be implemented with a simplified configuration.

That is, in the present invention, a 3-line address control I/F 101 having a function of preventing overtaking of lines for which image data is not set is arranged in the encoding processing section 4, and further,
A line memory 4 for three lines is arranged in the encoding section 2. As the overtaking prevention function for lines for which no image data has been set, for example, there is a method of setting an image data setting completion flag for each line, or a method of setting a line address in advance based on the paper size and reading density. and the image data input line, or by providing a counter to ensure that there is a difference of at least a certain level between the image data input line and the encoding line. This can be fully realized by using a general method such as a method of setting as follows. In this case, the image data supplied from the reading unit 8 is supplied to the line memory 4 under the control of the 3-line address control I/F 101 and is temporarily stored therein, and then the data is transferred to the data bus I/F 101.
The signal is sent to the encoding calculation unit 103 via F100, where it is encoded and then output as encoded data.

As described above, if the above arrangement is adopted, it is only necessary to add a new memory management function for three lines to the encoding processing section 4, and there is no need to add any other large memory management function. , it is possible to achieve sufficient hardware simplification.

[0056] Here, to explain the reason why data processing can be speeded up simply by having the capacity of the line memory 4 for three lines, MR and MMR encoding can be used to Since two-dimensional encoding is performed using the reference line, line memory for two lines is required, but if you have a line memory management function with a capacity for three lines, it will be possible to perform two-dimensional encoding while the encoding process is being executed. , the remaining 1
Since the line can be used as a pipeline for inputting image data, the data processing speed can be increased. Documents used in facsimiles and offices are usually around A3 size, with 4.
Even if high-definition reading of 00 dpi is performed, it is sufficient to control at most about 2 kbytes, so it would be uneconomical to use a processor for such control.

As explained above, the present invention has a line memory 4 for three lines and a three line address control I/F 1.
By simply adding 01, etc., economical pipeline processing can be performed and data processing can be accelerated. Therefore, the load on each control bus is reduced, a document reading speed of 10 Mb/s can be achieved, and the line density in the sub-scanning direction used in G3 facsimile is 7.7 lines/m.
Even in the case of m, it is possible to read an A4 size document in about 1 second and encode the read data. By the way, this speed is more than 10 times faster than normal G3 facsimile communication.
If communication is performed after data is stored in a memory or the like, it is possible to shorten the sender's waiting time for reading the original at a high cost and performance.

Next, a method of transmitting and receiving control signals between the decoding section 2 and the recording section 9 and between the line memory 6 and the decoding processing section 5 will be explained using FIG. 8.

In the figure, 110 is a data bus interface.
interface (I/F), 111 is 3 line address control I
/F, 112 is a recording control I/F, 113 is a decoding calculation section, and these are connected in a chain to form a decoding processing section 5.
It consists of

The recording control I/F 112 has a function of detecting a recording page start signal among the control signals sent and received via the control bus 21 and a function of outputting a recording page end signal. This function detects the recording page start signal and outputs the recording page end signal, and allows the start and end of recording for each page of the document without any other control. The timing is set with the recording section 9,
A data input/output timing signal built into the recording control I/F 112 is controlled to execute decoding of encoded data and recording of the decoded data. In addition, 3 line address control I/F111 and data bus I/F1
Reference numeral 10 controls the transfer of image data between the line memory section 6 and the decoding processing section 5, which will be described below.

Here, as in the case of encoding, when decoding encoded data, the greater the number of changing points of black and white pixels per unit length in the encoded data, the more The rate at which encoded data is decoded per unit time decreases. Generally, when recording decoded image data, the image data is recorded at a constant speed. If no memory means is arranged between the recording section 9 and the decoding section 2, the image data is recorded at a constant speed synchronized with the decoding speed of the encoded data. Must be. On the other hand, when the image data is recorded at a constant speed, in order to prevent undecoded data from being recorded if the decoding is delayed, the image data is usually - I am trying to suppress the recording speed of the data.

Furthermore, even when a memory means is arranged between the decoding section 2 and the recording section 9, when the decoding speed of encoded data is set to be relatively fast, the decoding speed is still relatively high. Since there is a risk of so-called overwriting occurring, in which restored image data is written again on a line where image data has not been output to the recording unit 9, decoding is not performed. There arises a need to add a function to prevent the recorded line from overtaking the recording line of the image data in the memory means.

Even in this case, in order to decode encoded data at high speed, the decoded image data is stored page by page in a memory such as a RAM, and after the storage is completed, the decoded image data is stored in a memory such as a RAM. If recording is performed, there is no need to make settings that take security into account with respect to decoding time, which can be expected to speed up the process, but this also requires a huge amount of bitmap page memory and requires memory management functionality. becomes large and becomes extremely uneconomical.

[0064] The present invention adopts a configuration that can cope with such a case, and by incorporating the above function into the decoding processing section 5, it is possible to avoid increasing the processing load on the external control element. It can be implemented with a simplified configuration.

That is, the present invention provides a 3-line address control I/F 111 in the decoding processing section 5 that has an overtaking prevention function that prevents the recording of decoded data from overtaking the decoding line. In addition, a line memory 6 for three lines is arranged in the decoding section 2. The overtaking prevention function can be fully realized by using a general method similar to the above-mentioned overtaking prevention function used during encoding. Also in this case, the encoded data is decoded by the decoding calculation unit 113, and the decoded image data is transferred to the 3-line address control I/F 111.
The data is input to the line memory unit 6 via the data bus I/F 110 under the control of the data bus I/F 110 and temporarily stored therein, and then read out and supplied to the recording unit 9 where it is recorded.

As described above, if the above arrangement is adopted, it is only necessary to add a new memory management function for three lines to the decoding processing section 5, and there is no need to add any other large memory management function. , it is possible to achieve sufficient hardware simplification.

Here again, to explain the reason why data processing can be speeded up simply by having the capacity of the line memory section 6 for three lines, MR and MMR decoding can be performed at one line before the decoded line. Since two-dimensional decoding is performed using the line as a reference line, a line memory for two lines is required, but if a line memory management function with a capacity for three lines is provided, the decoding process can be performed easily. During execution, the remaining one line can be used to output decoded data to be recorded in a pipeline manner, so data processing can be speeded up. In this case as well, the maximum size of documents used in facsimiles and offices is usually around A3 size, and even if high-definition reading at 400 dpi is performed, it is only necessary to control approximately 2 kbytes at most. Therefore, as in the case described above, it would be uneconomical to use a processor for such control.

[0068] As explained above, the present invention can also be applied in decoding encoded data and recording decoded data.
By simply adding a line memory section 6 for 3 lines, a 3-line address control I/F 111, etc., economical pipeline-like processing can be performed and data processing can be accelerated. . Therefore, the load on each control bus is reduced, and a speed of 10 Mb/s can be achieved when decoding encoded data, and at a line density of 7.7 lines/mm in the sub-scanning direction used in G3 facsimile. Also, it is possible to decode the encoded data of an A4 size document in about one second and record the decoded data. By the way, this speed is
This is more than 10 times that of normal G3 facsimile communication, and if the received encoded data is compressed and stored in a memory etc., and then output all at once after the communication is completed,
The record waiting time of the handler can be shortened, and a recording service that is comfortable for the handler can be realized with high cost performance.

[0069] The above explanation was made on the assumption that encoding and decoding can operate independently, but in this case, reading the original and decoding the decoded data are the same. It is possible to realize multi-operation that enables simultaneous operation with recording, which greatly contributes to improving services. If this multi-operation is executed, it will have the great effect of reducing hard costs, although it may require complex control or cause delays in execution time due to the adoption of time sharing, etc. It is something.

On the other hand, when the multi-operation is not performed, the configurations of the encoding section 1 and the decoding section 2 may be simplified, for example, the line memory sections 4 and 6 may be shared, or the data bus I
/Fs 100 and 110 can be combined and changed into a bidirectional bus I/F. Furthermore, 3 line address control I/F101, 111 and reading control I/F102
Since data input/output timing signals and the like of the recording control I/F 112 can also be shared with the recording control I/F 112, it becomes possible to obtain a more simplified configuration.

[0071] The above explanation has been made regarding the case where the encoding/decoding method according to the present invention is applied to a facsimile machine, but the models to which the encoding/decoding method according to the present invention can be applied are not limited to facsimile machines. It is also applicable to other models.

[0072] In the above explanation, the encoding unit 1
, decoding section 2, host MPU 7, reading section 8, recording section 9,
Although the communication control unit 10, code data memory unit 11, etc. have been described as having been configured individually, the present invention is not limited to such separate configurations, and the functions of each of the above-mentioned configurations can be combined. As long as they are included, these configurations can be combined as appropriate.

In particular, when configuring the encoding section 1 and the decoding section 2, the encoding section 1 and the decoding section 2 are integrated into one large-scale integrated circuit (LSI), as has been done in the past. Incorporating the LSI and connecting the external circuit with the LSI can be done using pins led out to the LSI, or the encoding section 1 and the decoding section 2 can be incorporated into one board and the connection between this board and the external circuit can be made. The connection may be made by pins led out to the board. However, when adopting such an LSI or board configuration, in addition to the conventionally derived pins,
It is necessary to provide a new pin for inputting and outputting the page end signal.

[0074] In addition, the medium for reading the original in the reading section 8 and/or recording data in the recording section 9 is limited to paper. Instead, a medium such as a magnetic device or an optical file may be used as appropriate.

Furthermore, at least the decoding section 2 and the recording section 9
It is also possible to combine the components into an integrated device and configure them in the form of a printer.

[0076]

As explained above, the encoding/decoding method according to the present invention allows the host controller 7 to issue necessary commands for each page of a document before starting the encoding or decoding process. After that, the encoding unit or decoding unit independently reads the original and reads the read data.
Since it is configured to perform encoding of the data, decoding of the encoded data, and recording of the decoded data, the host controller 7 manages the control for the entire period. The load is significantly reduced compared to the conventional method.

[0077] In the encoding/decoding method according to the present invention, the host controller 7
Because it is no longer necessary to send and receive control signals in real time, the encoding and decoding processes themselves are faster than conventional ones, and the speed is more than 10 times the original input/output speed of normal G3 facsimile. This has the remarkable effect of enabling original input/output processing.

[0078] Furthermore, the encoding/decoding method according to the present invention is as follows:
Since the conventionally required bitmap page memory is not used, the signal processing in this part is simplified, and the speed of other signal processing can be increased accordingly. Furthermore, by adopting the simplified signal processing described above, the load on the host control unit 7 is significantly reduced, so even though the control function has been improved, the use of a processor with high processing performance or the use of a multiprocessor is unnecessary. No longer needed, more advanced services
can be realized at low cost.

[0079] As a result, it is possible to provide a service that greatly shortens the waiting time of the handler and a service that improves man-machine handling at a high cost performance.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing a facsimile apparatus to which an encoding/decoding method of the present invention is applied.

FIG. 2 is a flowchart showing the flow of processing executed by a host MPU.

FIG. 3 is an explanatory diagram showing the temporal history of processing among the system, host control unit, and encoding unit during encoding.

FIG. 4 is an explanatory diagram showing the time course of processing among the system, host control unit, and decoding unit during decoding.

FIG. 5 is a hardware image diagram showing the time course of the process in FIG. 3 by the flow of control signals;

FIG. 6 is a hardware image diagram showing the time course of the processing in FIG. 4 by the flow of control signals;

FIG. 7 is a system diagram showing the configuration of an encoding unit and the flow of control signals.

FIG. 8 is a system diagram showing the configuration of a decoding section and the flow of control signals.

FIG. 9 is an explanatory diagram showing the amount of movement of an image in the sub-scanning direction.

[Explanation of symbols]

1 Encoding section 2 Decoding section 3 Encoding processing section 4, 6 Line memory section 5 Decoding processing section 7 Host MPU (host control section) 8 Reading section 9 Recording section 10 Communication control section 11 Code data memory section 12, 13 , 14, 15, 16, 17, 18, 19, 2
0, 21 Control bus 22, 23, 24, 25, 26, 27, 28, 29
Data line 40 Encoding/decoding section 41 Data input/output section 100, 110 Data bus interface (I/
F) 101, 111 3 line address control I/F102
Reading control I/F 103 Encoding operation section 112 Recording control I/F 113 Decoding operation section

Claims (8)

[Claims] Claim 1: At least a data input/output section, an encoding/decoding section, and a host control section that performs overall control, wherein the host control section performs encoding/decoding according to a request from the data input/output section. In response to the instruction, the encoding/decoding unit determines the amount of movement of data in the sub-scanning direction from the data input/output unit without going through the host control unit. An encoding/decoding method characterized in that data processing is performed sequentially based on information regarding the data processing, and a host control unit is notified of the end of the data processing. 2. The host computer comprises at least a reading unit that scans and reads a document, an encoding unit that encodes data read by the reading unit, and a host control unit that performs overall control over information processing. When the control unit receives a document reading request from the reading unit, the control unit sets an encoding mode and supplies an encoding preparation command to the encoding unit, and then the encoding unit transmits the request from the reading unit to the host. When a reading start request is received without going through the control unit and an encoding process is performed, and a page end request is received from the reading unit without going through the host control unit, the encoding process is completed and the encoding process is completed. An encoding method characterized in that an encoding end signal is supplied to a host control section, and the host control section supplies an encoding end command to the reading section. 3. The encoding method according to claim 2, wherein the encoding section includes a line memory section having a storage capacity for three lines, and temporarily stores the read data. 4. The encoding unit is characterized in that it includes a means for preventing the address of pixel data read from the line memory unit from overtaking the address of pixel data input to the line memory unit. The encoding method according to claim 2. 5. At least a decoding unit that decodes encoded data input from a receiving unit or an encoded data storage unit, a recording unit that records data decoded by the decoding unit, and an overall system for information processing. and a host control section that performs control, and when the host control section receives a document recording request from the reception section or encoded data storage section, it sets a decoding recording mode and sends a decoding command to the decoding section. Thereafter, the decoding unit receives a recording start request from the receiving unit or encoded data storage unit without going through the host control unit and performs a decoding process, and When a page end request is received from the encoded data storage unit without going through the host control unit, the decoding process is terminated and a decoding end signal is supplied to the host control unit, and the host control unit A decoding method characterized by supplying a decoding end command to. 6. The decoding method according to claim 5, wherein the decoding section includes a line memory section having a storage capacity for three lines, and temporarily stores the decoded data. 7. The decoding section includes means for preventing an address of pixel data when reading data stored in the line memory section from overtaking an address of pixel data input to the line memory section. 6. The decoding method according to claim 5, wherein: 8. The encoding unit and the decoding unit are configured in one large-scale integrated circuit (LSI) or one board, and a page end request is received and transmitted to the LSI or board. 6. The encoding/decoding method according to claim 2, further comprising a pin.