JPH06268830A - Data transmission controller - Google Patents

Abstract

PURPOSE:To reduce an overhead for coding processing by compressing data in advance before line setup independently of a minimum transmission time. CONSTITUTION:Before a line is set up with a destination facsimile equipment in the transmission processing of coded data executed by a CPU 11, sent picture data are coded by a predetermined coding method. After the start of transmission, a minimum transmission time present by a transmission watchdog timer 15 and a transmission time for the coded data during transmission are compared and when the transmission time of the coded data is shorter, fill bits are automatically inserted and the data are sent till the minimum transmission time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission control device, and more particularly to a data transmission control device suitable for controlling data transmission of compressed data in facsimile communication.

[0002]

2. Description of the Related Art As a conventional data transmission control device, there is, for example, one used in a G3 facsimile machine as shown in FIG. In FIG. 3, the data transmission control device 1
Is a CPU 2 that controls each unit according to a control program stored in the memory 4, and M
H (Modified Huffman), MR (Modufied Relative e-
lement address designate), MMR (Modified MR)
) Encoding circuit 3 for encoding (compressing) by an encoding method or the like
A facsimile communication procedure between the memory 4, which stores the control program executed by the CPU 2, the image buffer 5 which temporarily stores the encoded data encoded by the encoding circuit 3, and an external facsimile device. Run
The FAX-i / f 6 sends and receives image data, and each unit is connected to the bus 7.

In the data transmission control device 1 used in this G3 facsimile apparatus, as a technique for compressing unnecessary image information (redundancy suppressing process), an encoding method based on the recommendation of CCITT (International Telegraph and Telephone Consultative Committee) The MH, MR and MMR coding schemes are adopted as

The MH coding system (one-dimensional coding system) is
This is a method of encoding a black and white binary digital image by replacing it with a white or black run length code, and the code data of one line is represented by a terminating code or a terminating code + makeup code, A FOL (End Of Line) code is added after the code data.

If the encoded data is shorter than the minimum transmission time of one line, fill bits are inserted between the code data and the EOL code to secure the minimum transmission time. That is, in the G3 facsimile, the standard value of the transmission time of one line is 20 milliseconds, 0 as an option,
5, 10 and 40 milliseconds are specified, and when the encoded data is shorter than the transmission time of this standard value, a fill bit is inserted to secure the minimum transmission time.

In the MR coding system (two-dimensional coding system), one-dimensional coding system and K-1 times (K is standard =
2. High resolution = 4) two-dimensional encoding is alternately executed.
In this two-dimensional encoding, two-dimensional encoding is performed with reference to the line immediately before the encoded line, and the EOL code is added after the code data of each line. If the coded line is shorter than the minimum transmission time, a fill bit is inserted between the code data and the EOL code to secure a small transmission time, as in the MH coding method.

This minimum transmission time is determined based on the communication performance of the facsimile machine on the other side. That is, it is determined after the line is established with the partner facsimile machine. A conventional data transmission process based on the series of minimum transmission times will be described with reference to the flowchart shown in FIG.

In FIG. 4, first, when a line is established with the facsimile apparatus of the other party and the minimum transmission time is determined, the minimum transmission time is checked (step S1),
The encoding (compression) processing of the data of one line is started, and the encoding processing and the fill bit insertion processing that match the minimum transmission time are executed (steps S2 and S3). After this encoding processing and fill bit insertion processing, one-line data transmission processing is performed and the processing ends (step S4).

[0009]

However, in the data transmission control device used for such a conventional facsimile machine, the minimum transmission time is determined based on the communication performance of the facsimile machine on the other side. However, there is a problem that the data cannot be encoded in advance because the minimum transmission time is not determined unless the line has been established with the partner facsimile machine.

That is, the code data of one line is variable length data. For example, when all the lines are white, the code data becomes small and the code data in which 1 and 0 appear in the toggle becomes large. Whether or not the encoded data becomes shorter than the minimum transmission time determined after the line is established can be determined only by encoding the data after the line is established.

Therefore, in the data transmission control device used in the conventional facsimile apparatus, high-speed data encoding processing is required after the line is established, and in order to realize high-speed data encoding processing, high-speed encoding processing is required. There is also a problem that software and hardware for executing are required, which increases the cost.

Further, in the case of transmitting data which has been encoded and saved in the past by an electronic filing system or the like, the encoded data is once decoded and encoded again so as to meet the minimum transmission time. It has to be transmitted after being converted, which causes a problem that the processing procedure becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a data transmission control device which reduces the overhead of encoding processing by compressing data in advance before establishing a line regardless of the minimum transmission time.

[0014]

The means of the present invention are as follows.

According to the present invention, a compression means for compressing and storing one line of data by a predetermined compression method, a transmission means for transmitting the compressed data compressed by the compression means, and a compression means by the compression means. Transmission time setting means for setting a minimum transmission time for transmitting the compressed data, monitoring the transmission time of the compressed data transmitted by the transmitting means, and transmitting time at the end of transmission of the compressed data and the transmission time setting The minimum transmission time set by the means is compared, and if the transmission time of the compressed data is shorter than the minimum transmission time, the specific transmission data is transmitted after the transmission of the compressed data so as to continue the transmission until the minimum transmission time is reached. And a data adding means for adding.

[0016]

The operation of the means of the present invention is as follows.

According to the present invention, the data for one line is compressed and stored by the compression means by the predetermined compression method, the compressed data compressed by the compression means is transmitted by the transmission means, and the transmission means by the data addition means. The transmission time of the compressed data to be transmitted is monitored, the transmission time at the end of transmission of the compressed data is compared with the minimum transmission time set by the transmission time setting means, and the transmission time of the compressed data is shorter than the minimum transmission time. In this case, specific transmission data is added so that the transmission is continued after the transmission of the compressed data until the minimum transmission time is reached.

Therefore, the transmission data can be encoded before the line is established with the transmission destination, and at the time of transmission of the encoded data, the specific data can be added and transmitted in accordance with the preset minimum transmission time. The transmission data encoding process and the transmission process can be efficiently performed.

[0019]

EXAMPLES Examples will be described below with reference to FIGS.

1 and 2 are diagrams showing an embodiment of a facsimile apparatus to which the data transmission control device of the present invention is applied.

First, the structure will be described. FIG. 1 is a block diagram of the essential parts of a facsimile apparatus. In FIG. 1, the facsimile apparatus 10 includes a CPU 11, an encoding circuit 12, a memory 13, an image buffer 14, a transmission monitoring timer 15, an EOL detection circuit 16, a fill insertion circuit 17 and an F.
It is composed of AX-i / f18.

CPU (Central Processing Unit) 11
Controls each unit according to a control program or the like stored in advance in the memory 13, executes the sequence as the facsimile apparatus 10, and executes a transmission process of encoded data based on a transmission transmission time according to a transmission processing program described later.

The encoding unit 12 encodes (compresses) the image data of the transmission original read by a scanner (not shown) line by line by the above-mentioned conventional MH, MR, MMR encoding method, etc.
The encoded data is accumulated in the image buffer 14.

The memory 13 is a ROM (Read Only Memory).
y) and the like, and stores a control program and a transmission processing program executed by the CPU 11. The image buffer 14 is composed of a RAM (Random Access Memory) or the like, and forms a memory area for temporarily storing the encoded data encoded by the encoding unit 12.

The transmission monitoring timer 15 is set with a minimum transmission time for transmitting the encoded data, and the elapsed time until the transmission of the encoded data encoded by the encoding circuit 12 is completed, that is, the EOL detection circuit. E detected by 16
It is used to monitor the time until the detection of OL data.

The EOL detection circuit 16 detects EOL data added when transmitting encoded data, and outputs the detection result to the CPU 11. The fill insertion circuit 17
When EOL data is detected by the EOL detection circuit 16 before the time of the transmission monitoring timer 15 is up, the fill bit is output so as to be transmitted until the time is up. F
The AX-i / f 18 is controlled by the CPU 11 and executes a facsimile communication procedure with an external facsimile device to send / receive image data.

Next, the operation of this embodiment will be described.

The transmission process executed by the CPU 11 of this embodiment will be described with reference to the flow chart shown in FIG.

First, the image data of the transmission original read by a scanner (not shown) is M by the encoding unit 12 line by line.
The data is encoded by the H, MR, MMR encoding method or the like, but the compression rate is minimized regardless of the communication performance of the facsimile apparatus of the transmission destination. The encoded data is stored in the image buffer 14 and then stored in the FAX-i / f.
When the line is established with the destination facsimile machine by 18, the transmission process of the encoded data is started line by line.

In FIG. 2, after the transmission process of the code data is started, the detection of the EOL data added to the code data is checked (step S11). When the EOL data is detected, the transmission set at the start of the transmission process of the code data is checked. Check the timeout of the monitoring timer 15 (step S
12).

That is, in step S12, the transmission time until the EOL data of the encoded data for each line to be transmitted is detected is compared with the minimum transmission time preset in the transmission monitoring timer 15.

When the transmission monitoring timer 15 has not timed out in step S12, the fill bit is inserted until the minimum transmission time is reached (step S1).
3) Data is transmitted (step S14), and when the transmission monitoring timer 15 has timed out, E
The OL data is transmitted (step S14). Then E
The transmission of the OL data is checked (step S15), and when not transmitted, the process returns to the EOL data detection process of step S11, and when the EOL data is transmitted, this process ends.

On the other hand, when the EOL data is not detected in step S11, the transmission of the encoded data is continued (step S14) and the transmission of the EOL data is checked (step S15). If the EOL data is not transmitted, the EO of step S11 is determined.
Returning to the L data detection processing, when the EOL data is transmitted, this processing ends.

As described above, in the transmission process of this embodiment,
The image data to be transmitted is encoded by a predetermined encoding method before the line is established with the destination facsimile machine, and after the transmission is started, the transmission monitor timer 15 transmits the image with the preset minimum transmission time. The transmission times of the medium encoded data are compared, and if the transmission time of the encoded data is short, fill bits are automatically inserted and transmitted until the minimum transmission time is reached.

Therefore, as compared with the transmission processing procedure in which the transmission image data is encoded according to the minimum transmission time set after the conventional line establishment, the encoding processing can be executed before the transmission, so that the transmission processing can be performed in accordance with the transmission processing. It is not necessary to perform high-speed encoding processing, lower-speed encoding software and hardware can be applied, and the cost of the transmission data control device can be reduced.

Further, in the case of transmitting data which has been encoded and saved in the past by an electronic filing system or the like, the compression rate is set to the communication performance of the facsimile machine of the transmission destination as in the above embodiment. However, if compressed (encoded) so that it is minimized, there is no need for complicated processing procedures such as decoding encoded data once, encoding again to match the minimum transmission time, and then transmitting. Therefore, the transmission processing procedure can be simplified.

Further, the encoding for saving data and the encoding data for facsimile transmission can be shared, and an efficient data transmission system can be constructed. For example, it is possible to improve the user interface when the contents of the database are encoded in advance and automatically transmitted by the facsimile device.

[0038]

According to the present invention, the transmission data can be encoded before the line is established with the transmission destination, and when transmitting the encoded data, the specific data is added according to the preset minimum transmission time. It is possible to efficiently perform the encoding process and the transmission process of the transmission data.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a facsimile device to which a data transmission control device of the present invention is applied.

FIG. 2 is a flowchart of a coded data transmission processing program executed by the CPU of FIG.

FIG. 3 is a block diagram of a main part of a data transmission control device used in a conventional facsimile apparatus.

4 is a flowchart of an encoded data transmission processing program executed by the data transmission control device of FIG.

[Explanation of symbols]

 10 Facsimile device 11 CPU 12 Encoding circuit 13 Memory 14 Image buffer 15 Transmission monitoring timer 16 EOL detection circuit 17 Fill insertion circuit 18 FAX-i / f 19 Bus

Claims (1)

[Claims] 1. A compression unit for compressing and storing one line of data by a predetermined compression method, a transmission unit for transmitting the compressed data compressed by the compression unit, and a compressed data compressed by the compression unit. Transmission time setting means for setting a minimum transmission time when transmitting, and a transmission time at the end of transmission of the compressed data and the transmission time setting means for monitoring the transmission time of the compressed data transmitted by the transmission means. The set minimum transmission times are compared, and if the transmission time of the compressed data is shorter than the minimum transmission time, specific transmission data is added so that the transmission is continued after the transmission of the compressed data until the minimum transmission time is reached. A data transmission control device comprising: a data adding unit.