JP2830598B2 - Facsimile machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus, and more particularly, to a facsimile apparatus for transmitting newsprint.

[0002]

2. Description of the Related Art Conventionally, a facsimile apparatus of this type transmits compressed data of image information read from a newspaper without filling (FILL: pauses the flow of messages) in order to enhance transmission efficiency on a line. At the end of the recording, a response signal indicating the operating state of the receiver (absence of abnormality) was returned to the transmitting side.

[0003]

In the above-mentioned conventional paper transmission apparatus, since the compressed data is transmitted without filling, when the compressed data having a high compression rate is transmitted, the compressed data transmission is completed. It takes a considerably long time to complete the recording after decoding. Therefore, there is a disadvantage that the timer value for monitoring whether or not a response signal indicating the operation state at the time of the end of recording on the transmitting side is returned becomes very large.

If the transmitting side inserts a file into the compressed data on the paper surface and limits the minimum transmission time, the monitoring timer value can be reduced, but there is a disadvantage that the transmission efficiency of the line is reduced.

[0005]

SUMMARY OF THE INVENTION A facsimile apparatus of the present invention is a facsimile apparatus for transmitting compressed data of image information without adding a fill in one line, and decodes the compressed data after storing the compressed data in a buffer memory. A buffer memory for detecting a synchronization code in the compressed data upon input / output to / from the buffer memory and outputting a prohibition signal indicating prohibition of data transfer when the accumulated data in the buffer memory reaches a specified number of lines. Unit, and transmits the compressed data received from the line to the buffer memory unit, makes a retransmission request or fill transmission request to the transmission side by the prohibition signal output from the buffer memory unit, and in the case of the retransmission request, Has a communication control unit for discarding the received retransmission data.

[0006]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention.

In this embodiment, compressed data received from a digital forward line 1 is transferred to a buffer memory unit 4 and transmitted via a digital backward line 2 by a data transfer inhibit signal 9 output from the buffer memory unit. A retransmission request or a file transmission request to the communication side, and in the case of a retransmission request, a communication control unit 3 for rejecting the received retransmission data, and inputting the compressed data from the communication control unit 3 and storing the compressed data in the buffer memory. The data is transferred to the compressed data decoding unit 5, and when a synchronization code in the compressed data is detected during input / output to / from the buffer memory, the data transfer is performed when the stored data in the buffer memory reaches a specified line or when the storage area of the buffer memory is exhausted. And a buffer memory unit 4 for outputting a prohibition signal 9 for prohibiting the communication control unit 3 to the communication control unit 3.

Next, the operation of this embodiment will be described. The compressed data arriving from the forward line 1 is transmitted to the communication control unit 3
, And the compressed data is checked for errors.
If there is no error in the compressed data, it is transferred to the buffer memory unit 4. If there is an error, a retransmission request signal is transmitted via the backward line 2. The compressed data transferred to the buffer memory unit 4 is transferred to the compressed data decoding unit 5 and is decoded by the compressed data decoding unit 5 into image data. The newspaper image data decoded into the image data is transferred to the recording unit 6 and printed and recorded by the recording unit 6. When the speed of the compressed data input from the forward line 1 is higher than the recording speed of the recording unit 6, the compressed data is accumulated in the buffer memory unit 4. When the amount of compressed data stored in the buffer memory unit 4 reaches a specified value, a prohibition signal 9 indicating prohibition of data transfer is output.

FIG. 2 is a block diagram showing details of the buffer memory section 4 of the present embodiment. Buffer memory section input line 7
Is stored in the buffer memory 4-2 via the control unit 4-1. At the same time, the compressed data is input to the synchronization code detection unit 4-3, and the synchronization code added to the head of the compression data is detected. The detected output signal is input to the up / down counter 4-4, and is counted up by the up / down counter 4-4. Buffer memory 4
When reading out the compressed data stored in -2, a synchronization code in the compressed data is detected by a synchronization code detection unit 4-6 connected to an output line of the buffer memory unit. The detected output signal is input to the up / down counter 4-4,
The up / down counter 4-4 counts down. That is, the count value of the up / down counter 4-4 indicates the number of lines of the compressed data stored in the buffer memory 4-2. The output terminal of the up-down counter 4-4 generates a counter output when the counter value of the up-down counter 4-4 reaches a specified value. When the count value of the up / down counter 4-4 reaches a specified value, an inhibit signal 9 for inhibiting data transfer is output via an OR gate 4-5. Also, a signal indicating that there is no storage area in the buffer memory 4-2 is input from the memory control unit 4-1 to the other input terminal of the OR gate 4-5. This is to prevent the buffer memory 4-2 from overflowing when the compression rate of the compressed data is low and the data amount increases.

The data transfer prohibition signal 9 is input to the communication control unit 3. The communication control unit 3 sends a retransmission request to the transmission side in response to the input of the data transfer inhibition signal 9. The compressed data retransmitted in response to the retransmission request is discarded by the communication control unit 3. If the communication control unit 3 does not have a retransmission function, it sends a file transmission request. A fill or flag is received in response to a fill transmission request. By receiving the dummy data in this manner, the number of lines of the compressed data stored in the buffer memory unit 4 can be limited to a specified value.

[0011]

As described above, according to the present invention, by setting the amount of compressed data to be stored to a specified number of lines, a response signal from the receiver to the transmission of compressed data can be obtained while minimizing the decrease in the transfer efficiency of compressed data. And the timer value for monitoring the presence or absence of a response signal can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram illustrating details of a buffer memory unit according to the embodiment;

[Explanation of symbols]

 Reference Signs List 1 digital line (forward) 2 digital line (backward) 3 communication control unit 4 buffer memory unit 4-1 memory control unit 4-2 buffer memory 4-3, 4-6 synchronization code detection unit 4-4 up / down counter 4 -5 OR gate 5 Compressed data decoding unit 6 Recording unit

Claims (1)

(57) [Claims] 1. A facsimile apparatus for transmitting compressed data of image information without adding a fill in one line, storing the compressed data in a buffer memory, transferring the compressed data to a compressed data decoding unit, and inputting / outputting data to / from the buffer memory. A buffer memory unit that detects a synchronization code in the compressed data and outputs a prohibition signal indicating prohibition of data transfer when the accumulated data in the buffer memory reaches a specified number of lines; and A communication for performing a retransmission request or a fill transmission request to a transmission side based on the inhibit signal output to the buffer memory unit and output from the buffer memory unit, and in the case of the retransmission request, discarding received retransmission data. A facsimile apparatus comprising: a control unit.