JPS6358428B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a facsimile transmission processing system, and particularly to a fill bit insertion system during compressed data transmission.

In general, in facsimile systems, fill bits (invalid bits) are inserted into compressed data according to the data compression rate when transmitting compressed data in order to harmonize reading and recording speeds with transmission speeds.

Conventionally, when inserting fill bits into the compressed data, one
A certain minimum transmission time per line is determined, and if the transmission time for one line of compressed data is shorter than the minimum transmission time, a fill bit is inserted for each line to make the transmission time for each line longer than the minimum transmission time. The transmission was carried out with guarantees.

For this reason, while transmitting one page's worth of image data, a considerable amount of film bits must be transmitted, and even though data compression has been carried out to reduce the transmission time, the data The drawback was that the compression function could not be fully utilized.

On the other hand, in order to reduce the amount of inserted film bits, it is possible to increase the reading and recording speeds, but at present it is difficult to increase the recording speeds, and increasing the reading and recording speeds would make the entire device more expensive. There was a drawback.

SUMMARY OF THE INVENTION An object of the present invention is to provide a facsimile transmission processing system that can reduce the total amount of inserted fill bits without increasing reading and recording speeds and can efficiently transmit data.

In order to achieve this object, the present invention determines the minimum transmission time in units of one line based on the decoding processing time on the receiving side, and at the same time determines the minimum transmission time in units of multiple lines based on the recording processing time on the receiving side. ,
Set the corresponding number of bits after compressing the image data from each of these minimum transmission times, compare each of these set bit numbers with the actual number of bits after compressing the image data, and determine whether the actual number of bits is equal to each of the set bits. The present invention is characterized in that fill bits are inserted into the compressed data for each line and for each of the plurality of lines to compensate for the shortage in the number of lines.

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

FIG. 1 is a system configuration diagram of a facsimile apparatus showing an embodiment of the present invention, in which 1 is a reading device, 2 is a recording device, and 3 is a scanning device for performing main and sub-scanning of the reading device 1 and the recording device 2. , 4 is a mechanism control device that controls those mechanisms, 5 is 32 lines x 2
a buffer memory having a storage capacity of 6, a device for compressing and decoding data line by line;
7 is a modem, 8 is a transmission control device for executing facsimile control procedures, 9 is an operation display device for communicating with an operator, 10 is a system controller for controlling the above devices, and 11 is for connection to a line, etc. It is a network control device that performs

Among these, the reading device 1, recording device 2, and scanning device 3 are movable back and forth in the main scanning direction along the scale plate 12 fixed to the device, as shown in FIG. 2a. It is comprised of a carriage 13 provided in the main body, and a DC motor 14 that drives the carriage 13.

A slit 12a is provided on the plate 12 to define the main scanning position during reading and recording.
and slit 1 that defines the effective screen width for treating the reading and recording scan as valid.
2s and 12e are provided.

A reading head 13a, a recording head 13b, and a slit detector 13c for detecting each slit as the carriage 13 moves are provided on the carriage 13.

More specifically, the document 1 is placed on the reading head 13a.
A plurality of bits of reading elements are arranged to read 32 lines of image information in the sub-scanning direction from 5 to 5 in the sub-scanning direction. ing.

Further, a stylus for recording image information for 32 lines in the sub-scanning direction on the reading paper 17 is arranged on the recording head 13b.

A light emitting element 13c ₁ and a light receiving element 13c ₂ are arranged on the detector 13c at positions facing each other with the plate in between, and are configured to extract a predetermined signal from each slit as the detector 13c moves.

In addition, 18 is a pulley, 19 is a wire for reciprocating the carriage 13 by the DC motor 14, 20 is a conveyance roller, 21 is a contact glass, 22 is a counter electrode, and 23 is for document illumination attached to the optical system 16. It is a light source lamp.

With this configuration, when the DC motor 14 is started by the mechanism control device 4, the carriage 13 is driven from the home position, and the carriage 13 is driven from the home position according to the output from the slit detector 13c as shown in FIG.
The speed increases as shown in , and eventually reaches a constant speed. When the carriage 13 reaches a certain speed, the detector 1
3c detects the slit 12s as shown in FIG. 3b, the reading head 13a responds to the slit 12a detected thereafter as shown in FIG. 3c.
Alternatively, the recording head 13b is driven to read or record image data in units of 32 bits in the sub-scanning direction. In this way, the image data is processed as the carriage 13 moves, and eventually the slit 12
When e is detected, it means that processing for 32 lines has been completed, so the carriage 13 is decelerated, turns around at the end, and returns from the home position at high speed. During this time, the original 15 or the reading paper 17 is fed in the sub-scanning direction as shown in FIG. 3d. This kind of operation is repeated, and as shown in Figure 4, 32
Reading or recording processing of the original 15 or reading paper 17 is performed line by line.

In this way, the image data of 32 bits each in the sub-scanning direction output from the reading device 1 at the time of transmission is stored in one block memory for 32 lines in the buffer memory 5, and is stored in the block memory for 32 lines on the other side. The data is sequentially taken out line by line from the memory and output to the compression/decoding device 6. Also, during reception, the image data decoded from the compression/decoding device 6 is sequentially stored one line at a time in one 32-line memory in the buffer memory, and from the other 32-line memory in the sub-scanning direction. Each 32 bits are extracted and output to the recording device 2.

FIG. 5 shows signals exchanged between buffer memory 5, compression/decoding device 6, and system control 10 at that time.

In this embodiment, since the time required for processing such as batch recording of 32 lines is 640 ms, the minimum transmission time per 32 lines is set to 640 ms.
Furthermore, since image data is decoded line by line and requires a maximum of 5 ms to decode one line, the minimum transmission time per line is set to 5 ms.

Next, its operation will be explained below.

At the time of transmission, the system controller 10 outputs a clear signal _s1 to the buffer memory 5 to initialize the internal register, and outputs a transmission mode set signal s2 to set the buffer memory ₅ to the transmission mode. The system controller 10 also sends a clear signal s ₃ to the compression/decoding device 6.
output to initialize the status register of the compression/decoding device 6, output the transmission mode set signal _s4 to instruct the compression operation, and output the fill bit control signal _s5 or _s6 to set the output per line. Indicate the minimum transmission time, for example 5ms according to _s5 .

When the initial settings of the buffer memory 5 and the compression/decoding device 6 are completed, the system controller 10
issues a command to the mechanism control device 4 shown in FIG. 1 to start the above-mentioned reading operation in units of 32 lines.

At the same time, the system controller 10 outputs a buffer start signal _s7 to the buffer memory 5,
When either one of the 32 lines of memory blocks inside the buffer memory is filled with the image data _s8 output from the reading device 1, a start signal _s9 is output to the compression/decoding device 6.

When the buffer memory 5 is started in this way, as shown in the flowchart of FIG.
It is determined whether or not there is at least one line of image data to be taken out to the compression/decoding device 6 in either block memory in the buffer memory, and if there is, the buffer ready signal _s10 is output to the compression/decoding device 6. . At the same time, one of the block memories in the buffer memory is empty and the reading device 1
When it is in a state where it can accept the image data s ₈ from , it outputs a buffer empty signal s ₁₁ to the system controller 10 .

The system controller 10 outputs a reading operation command to the mechanism control device 4 at intervals of 640 ms while the buffer empty signal _s11 is being output. Based on this command, the 32 lines of image data _s8 read by the reading device 1 are alternately stored in the block memory that is empty at that time.

On the other hand, when the compression/decoding device 6 starts, as shown in the flowchart of FIG.
s ₅ , the compression/decoding device 6 compresses the number of bits N after compression corresponding to the minimum transmission time of 5 ms per line.
Set. Next, the compression/decoding device 6, as shown in the timing chart (negative logic) of FIG.
Binary strobe signal s ₁₂ buffer memory 5
The image data _s13 for one line is fetched from the buffer memory 5 in synchronization with the clock _s14 .
At the same time, it indicates the separation between lines.
Generates an EOL code. Thereafter, the captured image data for one line is encoded and compressed using the Modified Hoffman method. When this is completed, the number of bits M of the compressed data is compared with the previously set value N, and if the number of bits of the compressed data is less than the number N of bits corresponding to the minimum transmission time per line, the number of bits M of the compressed data is Insert minute file bit. In this way, data compression for each line and fill bit insertion for each line are performed as necessary.

Eventually, when all 32 lines of image data stored in the memory block in the buffer memory 5 have been compressed, the processing time will be 640 m.
If it is less than s, there is no data for each line to be taken out in the buffer memory 5, so the buffer ready signal _s10 is no longer output, and filling bit insertion is started based on this. This fill bit is inserted for up to 640 ms, and after 640 ms has passed, data that can be taken out line by line is again stored in the buffer memory, and as a result, a buffer ready signal _s10 is output, and the above series of operations is repeated.

In this way, all one page of the manuscript is read,
When the data compression is finished, the system controller 10 gives an instruction to stop the compression operation.
Generates an EOL code and ends the above series of operations.

On the other hand, during reception, the compression/decoding device 6 removes fill bits inserted for each line and every 32 lines, and each time it completes decoding for one line, as shown in the timing chart of FIG. ,
A decoded data go signal s ₁₅ indicating the effective data range for one line, decoded data s ₁₆ , and an end-of-line sync signal s ₁₇ indicating the division between lines are output to the buffer memory 5 . The buffer memory 5 sequentially stores the decoded data s ₁₆ for each line in an empty block memory, and outputs a storage data ready signal s ₁₈ to the system controller 10 when storage for 32 lines is completed. The system controller 10 issues a command to the mechanism control device 4 based on this signal _s18 , and sequentially stores the image data _s19 of 32 bits in the sub-scanning direction output from the buffer memory 5 as described above.

In this way, in this embodiment, the minimum transmission time is set to 5 ms per line, and the minimum transmission time per 32 lines is set to 640 ms, and fill bits are inserted based on these, so the amount of fill bits inserted is reduced. Transmission efficiency increases considerably.

For example, if the modem transmission rate is 9600bps and the minimum transmission time per 32 lines is 640ms, then 640/3
If we determine the minimum transmission time per line as 2 = 20 ms and insert fill bits for each line, we will have to insert a considerable number of fill bits, but as in the case of this example, we decide the amount of fill bit insertion in units of 32 lines. As a result, the 32 lines of compressed data naturally include a considerable amount of compressed data with a length exceeding 20 ms, so the data compression time for 32 lines is approximately 640 ms, and most of the time it is necessary to insert fill bits. The need disappears.

Furthermore, since the present embodiment also guarantees the minimum transmission time for each line, there is no possibility that the receiving side decoding process will fail. Furthermore, since the minimum transmission time is as short as 5 ms, the amount of fill bits to be inserted can be extremely small.

As described above, according to the present invention, a facsimile transmission processing system with extremely high transmission efficiency can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram of a facsimile apparatus showing an embodiment of the present invention, and FIG. 2 is a specific configuration diagram of the reading device, recording device, and scanning device portions in FIG. is its side sectional view,
Fig. 3 is a time chart for explaining the operation of Fig. 2, Fig. 4 is an explanatory diagram of the scanning state of Fig. 2, and Fig. 5
The figure is an explanatory diagram of input/output signals between the buffer memory, compression/decoding device, and system controller in FIG. 1, FIG. 6 is a flowchart for explaining the operation of the buffer memory in FIG. 5, and FIG.
Flowchart for explaining the operation of the compression/decoding device shown in the figure, FIG. 8 is an operation timing chart of the compression/decoding device of FIG. 5 during transmission, and FIG. 9 is a reception diagram of the compression/decoding device of FIG. 5. This is an operation timing chart at the time of operation. DESCRIPTION OF SYMBOLS 1... Reading device, 2... Recording device, 3... Scanning device, 4... Mechanism control device, 5... Buffer memory, 6... Compression/decoding device, 7... Modem, 8...
...Transmission control device, 9...Operation display device, 10...
System controller, 11...Network control device, 1
2...Scale plate, 12a, 12e, 12
s...slit, 13...carriage, 13a...
...Reading head, 13b... Recording head, 13c...
...Slit detector, 13c ₁ ...Light emitting element, 13c ₂
... Light receiving element, 14 ... DC motor, 15 ... Original, 16 ... Optical system, 17 ... Recording paper, 18 ...
Pulley, 19...Wire, 20...Conveyance roller, 21...Contact glass, 22...Counter electrode, 23...Light source lamp for document illumination.

Claims (1)

[Claims] 1 In a facsimile transmission processing method that inserts film bits according to the data compression rate of the image data read on the sending side and transmits it to the receiving side, the minimum transmission time for each line is determined based on the decoding processing time on the receiving side. At the same time, the minimum transmission time for multiple lines is determined based on the recording processing time on the receiving side,
Set the corresponding number of bits after compressing the image data from each of these minimum transmission times, compare each of these set bit numbers with the actual number of bits after compressing the image data, and determine whether the actual number of bits is equal to each of the set bits. A facsimile transmission processing method characterized in that fill bits are inserted into the compressed data for each line and for each of the plurality of lines to compensate for the shortage in the number of lines.