JPH02134979A - Device for thinning stored facsimile code - Google Patents

Abstract

PURPOSE:To decrease the processing speed of a decoding circuit, to reduce the cost of the title device, and to miniaturize the device by providing a line synchronizing code detection circuit and a code thinning circuit. CONSTITUTION:Code data are stored in a code storing circuit 1. The code data in the code storing circuit 1 are successively sent to a line synchronizing code detection circuit 2 and a code thinning circuit 3 as a storage code 5. The line synchronizing code detection circuit 2 searches a synchronous code in the data sequence of the storage code 5 and informs the code thinning circuit 3 of the searched result. The code thinning circuit 3 recognize a segment in the line of the storage code 5 from the result, thins the storage code 5 according to a previously determined thinning ratio, and sends the thinned storage code 5 to a line control circuit 4 as a transmission code 7. Thus, a high-speed decoding circuit to operate simultaneously with a coding circuit becomes unnecessary, and the cost can be widely reduced and the device is miniaturized, as well.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for transmitting accumulated facsimile codes, and more particularly to an apparatus for transmitting accumulated codes by thinning out sub-scanning lines.

2. Description of the Related Art In conventional facsimile machines, originals to be sent are stored in a memory and sent at a designated time, or the same original is sent to a large number of recipients. In such a case, storing the document data as is in the memory would require a large capacity, so the data is compressed by encoding and then stored to make efficient use of the memory.

Problems to be Solved by the Invention In the above-mentioned apparatus, for example, if the line density of the image stored in the memory and the line density of the image sent to the destination device are different,
The accumulated codes may be transmitted after thinning out the sub-scanning lines. For example, the sub-scanning line density of 7.7 I/mn+, which is an option for G3 facsimiles, has better image quality than the standard sub-scanning line density of 3.85 l/mm, and is widely used. Because of this, there are some devices that are not equipped. If such a device is the other party's machine and you store originals at 7.71/mm and send them to such a machine, the other party's machine will not be able to receive 3.85 l/mm L, so normal communication will not be possible. There will be no.

In order to solve this problem, during communication, after decoding the stored data and returning it to image data, thinning out the sub-scanning line density of one stroke data and making it image data with the line density of the other machine, A device has been proposed that encodes the data and sends it to the other party's machine. FIG. 5 is a block diagram showing an example of this device, in which 11 is a code storage circuit, 12 is a decoding circuit, 13 is a scanning line thinning circuit, 14 is an encoding circuit, and 15 is a line control circuit.

The code data stored in the code storage circuit 11 is decoded by the decoding circuit 12 and becomes image data. The image data is appropriately thinned out line by line by a scanning line thinning circuit 13 in accordance with the sub-scanning line density capability of the other machine.

The thinned out image data is encoded by an encoding circuit 14,
The line control circuit 15 outputs the signal to the line and sends it to the other party's machine. In the above example of the linear density value, the code data stored in the code storage circuit 11 and the image data decoded by the decoding circuit 12 are 7.71/mm, and the image data is reduced to 1 by the scanning line thinning circuit 13. Thinned for each line to 3.8
51/mm. The converted image data is encoded as a 3.851/mm line by the encoding circuit 14 and output to the line by the line control circuit 15.

However, the above-described apparatus requires a high-speed decoding circuit that operates simultaneously with the encoding circuit in order to once decode all lines of image data before thinning. In the above-mentioned example of the linear density value, it is necessary to decode two lines of accumulated encoded data while sending one line of encoded data to the other party's device. This results in having a decoding circuit that is twice as fast as the encoding circuit. This has the drawbacks of increased cost and increased device size.

The present invention has been made in view of the above-mentioned conventional situation,
SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a novel facsimile code thinning device which makes it possible to eliminate the above-mentioned drawbacks inherent in the prior art.

Means for Solving the Problems In order to achieve the above object, an apparatus for thinning out accumulated facsimile codes according to the present invention is comprised of a line synchronization code detection circuit and a code thinning circuit.

EXAMPLES Next, preferred embodiments of the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention. Referring to FIG. 1, reference number l indicates a code storage circuit, 2 a line synchronization code detection circuit, 3 a code thinning circuit, and 4 a line control circuit.

The code storage circuit 1 stores code data. As shown in FIG. 2, this data includes a line synchronization code (hereinafter referred to as EOL) indicating the end of one line after the code for one scanning line.
An abbreviation ``n'' is added. Furthermore, the data of each line must be encoded using a so-called one-dimensional encoding method that does not utilize correlation with the previous line, at least for the line following the line to be thinned out.

The code data in the code storage circuit 1 is sequentially sent as a stored code 5 to the line synchronization code detection circuit 2 and the code thinning circuit 3. The line synchronization code detection circuit 2 searches for EOL in the data string of the storage code 5, and when detected, notifies the code thinning circuit 3 of the detection of EOL using the line synchronization code detection signal 6. The code thinning circuit 3 learns the line separation of the storage code 5 from the line synchronization code detection signal 6 sent from the line synchronization code detection circuit 2, thins out the storage code 5 according to a predetermined thinning rate, and uses it as a transmission code 7. It is sent to the line control circuit 4. Line control circuit 4 outputs transmission code 7 to the line.

Figure 3 shows the accumulation code of 7.71/n+m as 3.85.
This figure shows how thinning is performed when a 17 mm transmission code is used.

In this case, one line will be thinned out to two lines.

Of the input accumulation code 5, the n+1th line and the n+th line
This shows a case where the third line is discarded, and the n-th line, the n+2-th line, and the n+4-th line remain, and they are output to the line.

In this example, the nth line, the n+2th line, and the n+th line
The 4th line is always thinned out because the previous line is thinned out.
It must be encoded using a one-dimensional encoding method that does not utilize correlation with the previous line. Otherwise, these lines cannot be decoded successfully.

In order to avoid having to consider in advance which lines will be thinned out and then alternately switch between the one-dimensional encoding method and the two-dimensional encoding method and then encode and store them, encode all lines using the one-dimensional encoding method. All you have to do is convert it and accumulate it. In this case, the compression rate of the one-dimensional encoding method is generally lower than that of the two-dimensional encoding method, so the memory capacity of the code storage circuit required is slightly larger, but the same encoding can be performed without making any judgment at the time of encoding. It can be encoded and stored using a method.

Detection of line synchronization codes and code thinning according to the present invention are considerably faster than decoding all normally input data, and are easy to implement and inexpensive.

FIG. 4 is a block diagram showing a second embodiment of the present invention.

In the first embodiment, the code data after thinning out is directly put into the line control circuit and sent to the other party, but this is transferred to the fourth embodiment.
As in the second embodiment shown in the figure, the coded data after thinning is input to the decoding circuit, once restored to image data, and then encoded by the encoding circuit, and the encoded data is used for line control. Of course, it may be put into the circuit 6' and sent to the other party's machine. In this case, a decoding circuit is required compared to the first embodiment, but its processing power may be equivalent to that of the encoding circuit, and unlike the conventional device, high speed corresponding to the thinning is required. It has the advantage of not having Further, in this case, there is an advantage that the encoding method of the accumulated data and the encoding method of the code sent to the other party's device may be different.

As described in detail, according to the present invention, accumulated code data is thinned out by t of code data by detecting a line synchronization code. Compared to the above device, there is no need for a high-speed decoding circuit that operates simultaneously with the encoding circuit, and when a decoding circuit is used, it only needs to have the same capability as the encoding circuit, which can significantly reduce costs. Moreover, it is possible to achieve the effect that the device can be made smaller.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of a thinning device according to the present invention. DESCRIPTION OF SYMBOLS 1... Code storage circuit, 2... Line synchronous code detection circuit, 3... Code thinning circuit, 4... Line control circuit. FIG. 3 is a diagram schematically showing the accumulated code 5 input to the code thinning circuit 3, the transmitted code 7 output after being thinned out, and the code data sent to the partner machine. FIG. 4 is a block diagram showing a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Code accumulation circuit, 2... Line synchronous code detection circuit, 3... Code thinning circuit, 4... Decoding circuit, 5
. . . Encoding circuit, 6' . . . Line control circuit FIG. 5 is a block diagram showing an example of a conventional device of this type.

Claims (1)

[Claims] A device that transmits facsimile codes after once storing them includes a line synchronization code detection circuit that detects a line synchronization code from code data from a code storage circuit, and a line synchronization code detected by the line synchronization code detection circuit that is input in advance. An apparatus for thinning out accumulated facsimile codes, comprising a code thinning circuit that thins out the accumulated code data according to a predetermined thinning rate.