JPH0346866A - Encoded data processing system - Google Patents

Abstract

PURPOSE:To efficiently solve a problem such as the absence of a horizontal line due to the thinning out of lines by judging the correlation between a code line and a reference line from two-dimensional position information. CONSTITUTION:An MR code word is interpreted even as to a line to be thinned out; when the object line is in vertical mode, decoding is omitted while the line is considered to be represented sufficiently by the array of picture elements of the reference line and when in horizontal mode, the run length of a white/ black picture element pair is reduced and ORed with the reference line to store the run length the white/black picture element pair indicating the horizontal mode. Consequently, a code in vertical mode which is said to occupy 75% of picture element data of a line drawing, a character, etc., is omitted to speed up the processing, and the reduction result of good picture quality is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial field of application The present invention is applicable to image data processing for coded data handled by filing systems for documents and image data using storage devices such as optical disks, facsimile machines, etc. The present invention relates to a code data processing method that performs reduction processing according to a reduction rate.

(b) Conventional technology In the conventional code data processing method in which code data is reduced according to the reduction ratio, in the sub-scanning direction, the number of scanning lines of the image data to be restored is thinned out according to the reduction ratio. I was doing a reduction. See the article entitled "OA Workstation" (pages 56-67) in Sanyo Giho Vol. 20, No. 1 (February 1989).

(C) Problems to be Solved by the Invention However, in the conventional code data processing method, the reduction processing in the sub-scanning direction simply thins out the number of scanning lines, which may lead to the disappearance of horizontal lines, for example. was there. In addition, as a means to prevent this, it is possible to perform corrections such as taking the logical sum of the data of the scanning line to be thinned out and the data of either the upper or lower scanning line.
In addition to prolonging the processing time, since all pixels are saved, there are many dots in the entire image, which causes the white parts to become blurred.

(d) Means for Solving the Problems In order to solve the above-mentioned problems, the encoded data processing method of the present invention has the following features: Taking advantage of the fact that there is a strong correlation in the vertical direction, if the difference in pixel arrangement between the code line and the reference line is within 3 dots, the positional relationship with the reference line is encoded as vertical mode; The white pixel and black pixel length are each encoded as the horizontal mode,
If the pixel rows are not adjacent at all, the code data based on the MR encoding method that constitutes the code word is adopted as the code data to be subjected to reduction processing as bus mode, and the two-dimensional positional information of the MR code word is used. In other words, the correlation with the reference line and the first scan line is considered, and if the correlation is close (for example, in vertical mode), the pixel data is The pixel data is deleted, and when the correlation is not dense (for example, in horizontal mode), the pixel data is stored.

(e) Effect In the present invention, we focus on the fact that the MR encoding method has two-dimensional position information, and if there is a strong correlation between the reference line and the encoded line in the coded data of the line to be thinned out, the decoding If the correlation is not very strong, decoding is performed by performing a logical OR with the data of the reference line, so that the reproduction quality of the reduced reproduced image is the same as that of the original image. Something close to the quality =
can get.

(f) Example This example will be explained in detail using the drawings. FIG. 1 is a block diagram showing an example of a code data processing device that performs the code data processing method of the present invention.

<1) is a communication I/F device that exchanges images by sending and receiving code words with a remote location, (2) is a storage device such as an optical disk that stores code data, and (3) is a device that controls code data. Part (5) is an image memory for temporarily storing the restored image data, (4) is a display device such as a CRT display for displaying the restored image data, and (5) is each of these components. The controller is configured to perform various controls and also process code data in a built-in code data processing unit.

The coded data received by the communication 17F device (1) or read from the storage device (2) in which coded data is stored in advance is taken into the control unit (5) and restored to image data. . At this time, reduction processing is simultaneously performed using a prespecified reduction ratio. The restored image data is stored in the image memory (3). Image memory (3)
The image data stored in C is sent to the display device (4).
The information is displayed on the RT display or the like.

FIG. 2 shows the processing contents of the present invention using a specific example.

The following processing is performed on the encoded lines to be thinned out. (a) and (b) show examples of pixel arrangement in certain image data, where (a) is for the horizontal mode in the MR encoding method, and (b) is for the same < vertical mode in the MR encoding method. This is the case for mode. In the vertical mode, the difference in pixel arrangement from the reference line is represented by three dots on the left and right from the point of change in the reference line, which can be said to indicate that the correlation between the reference line and the encoding line is close (strong). .

In the horizontal mode, the arrangement of pixel data in the main scanning direction is expressed by a run length of white/black pixels, and can be said to indicate that the correlation between the reference line and the encoded line is not close (not very strong). For example, if the reduction ratio is 7/10, if you leave only 7 out of 10 lines and thin out 3 lines, simply thinning out may cause the disappearance of horizontal lines, which may cause problems in terms of image quality. Become.

Therefore, the MR code word is also interpreted for the line to be thinned out, and if the line to be thinned out is in vertical mode, the pixel is (
As shown in b), the decoding is omitted as it is assumed that the pixel arrangement of the reference line can be sufficiently expressed, and in the horizontal mode, the arrangement of white/black pixels in the horizontal direction is important, not the difference in the pixel arrangement of the reference line. Therefore, after performing reduction processing on the run length of the mortar/black pixel pair, the run length of the mortar/black pixel pair indicated by the horizontal mode can be saved by performing a logical sum with the reference line. do.

Compared to the conventional simple thinning method, which can process at high speed but may cause the disappearance of horizontal lines, lines that should be thinned out to prevent the disappearance of horizontal lines etc. are also decoded. By omitting the vertical mode decoding, which is said to account for 75% of image data such as letters and letters, it is possible to increase the speed and obtain a reduction result with good image quality.

FIG. 3 shows the code data processing section in the control section (5). The code data is input to the MR code interpreter (6), which determines each mode, detects the amount of movement of the change point, counts the run length, etc. based on the change points of the reference line from the change point extractor (7). Interpretation takes place.

The output from the MR code interpreter (6) is sent to the change point extractor (7).
, is sent to the reduction processing unit (8). Change point extraction part (7)
Then, based on the captured data from the MR code interpreter (6), position information of the change point of the reference line for the next code data is generated. In order to generate a reference line, the data of the line to be thinned out is not restored, but the position information of the change point is extracted. The output from the MR code interpretation section (6) is simultaneously sent to the reduction processing section (8), where reduction processing is performed according to the reduction rate based on data such as change points in the reference line from the change point extraction section (7). The image data is reproduced.

(G) Effects of the Invention As is clear from the above description, the present invention focuses on the fact that the MR encoding method has two-dimensional position information in code data reduction processing, and calculates the correlation between code lines and reference lines. By making a judgment based on two-dimensional position information, problems such as lack of horizontal lines due to line thinning can be efficiently solved.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention. FIG. 2 is an explanatory diagram showing the details of the reduction process. FIG. 3 is a block diagram for realizing the reduction process. (1) is a communication I/F device, (2) is a storage device, (3)
is an image memory, (4) is a display device, (5) is a control unit, (
6) is the MR code interpretation section, (7) is the change point extraction section, (8)
is the reduction processing section. Figure 1

Claims (1)

[Claims] (1) Scan the image data and determine not only the length of black pixels and white pixels, but also the positional relationship of the change point of a pixel from black to white or from white to black in a certain row with the change point in the previous row. In a coded data processing method using a modified read (MR) encoding method that configures codewords based on , when performing reduction processing using coded data, the reduction in the sub-scanning direction is Scan lines are thinned out, but the pixel data of the scan line to be thinned out takes into account the correlation between that line and the previous line, and if the correlation is close, the pixel data is deleted. However, if the correlation is not dense, the coded data processing method is characterized in that processing is performed to preserve the pixel data.