JPS61141481A - Character image data processing method and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a character image data processing method and a character image data processing apparatus used to implement the method.

[Conventional technology]

In recent years, automatic phototypesetting machines have been proposed that perform phototypesetting by projecting characters, symbols, etc. onto a cathode ray tube and projecting the images onto photosensitive materials through a lens. The character signal generation method used for this purpose is as follows:
There is a system in which a character is divided into several pixels and the white and black of each pixel are output in correspondence with digital rlJ and rOJ.

[Problem that the invention seeks to solve]

However, in such conventional systems, for complex characters such as Kanji, each character is
It is necessary to decompose it into about 50 pixels, and if all of this is stored in a storage device, there will be 62,500 pixels per character.
A storage capacity of several bits is required, making the device expensive and impractical.

In response, various techniques have been proposed for processing text image data that reduces storage capacity by compressing the data. These are the contents of pattern Pm (binary data, n-pit gradation data) for pattern row 1 of one continuous pattern Pm (Pm indicates the m-th pattern) as shown in FIG. 5(a) K. (hereinafter referred to as pattern data) and the number of repetitions thereof is stored to obtain pattern string 2. As shown in Fig. 5(b), two different pattern data, PB#PC... are consecutive. For pattern sequence 3, which also stores a repetition number of 1, pattern sequence 4 becomes pattern sequence 4, which increases the number of pattern data to be stored and makes it impossible to compress the data.

This invention was made by focusing on such conventional problems, and when the same pattern data is repeated, it is made into a sufficiently compressed pattern string, and when different pattern data is consecutive, it is made into a sufficiently compressed pattern string. 31 This invention aims to provide a character image data processing method and a character image data processing device in which 11 patterns are arranged in a row and stored. In the character image data processing method, when the input character image pattern data of Pm is continuous Rc times, it is expressed as a pattern sequence of P m e P m + Rc, and other than this, the pattern data is used as is. is written in order to obtain a high data compression rate. Further, the character image data processing device stores the pattern data immediately before pattern Pm (Pm-1) in the data holding unit, compares the pattern data of Pm and Pm-1 with a data comparator, and when they match, While incrementing the repeat counter, the coincidence is stored in the repeating pattern detection holding unit, and when the pattern data of Pm and Pm-1 no longer match, Pm-1 and Pm-2 in the same pattern detection holding unit are When the pattern data of Pm-1 stored in the data holding unit and the count value Rc of the repeat counter match,
), Pm=1, compressed data of Pm-11Rc, if they do not match, only pattern data of Pm-1,
The compressed data generator outputs the compressed data according to the output of the controller.

[For production]

When a pattern Pm of a character image is input, the data comparator compares the pattern data of this Pm with P of the data holding section.
The pattern data of m-1 is compared, and when Pm-Pm-1 is obtained, the control unit advances the repeat cycle and stores the coincidence in the same pattern detection unit. Furthermore, when Pm''+sPm-1, the control section determines that the contents of the same pattern detection section are Pm-1=Pm
-2 or not, and when J'm-1 = Pm-2, the pattern data of Pm-1 stored in the data holding unit and the count value Rc so far based on the repeat count are sent to the compressed data generating unit. , Prrr by the compressed data generator
The compressed data of l*Pm-1+Rc is output.

In addition, when pm-1'q Pm-2, if the same pattern data is not consecutive, the pattern data of Pm-1 stored in the data holding section is sent as is to the compressed data generation section, and the compressed data is The generation section outputs pattern data of Pm-1.

In this way, it is possible to significantly reduce the storage capacity.

[Embodiments of the invention]

FIG. 1 is a block connection diagram showing a character image data processing apparatus of the present invention, and in parentheses are shown signals output from each part when pattern data of Pm is input. In the figure, 30 is a data holding section that holds pattern data of the previous pattern Pm-1, and 31 is an input Pm
pattern data and Pm stored in the data holding unit 30
32 is a control unit that performs various types of control; 33 is a repeat counter (initial value Rc = 1) that counts the number of times the same pattern data is continuously repeated; 34 is the same pattern detection holding unit 35 that stores that the pattern data of the previous two patterns Pm-1#Pm-2 are the same.
is a compressed data generator.

Next, a method for processing character image data will be described with reference to this block diagram.

■When a character image pattern Pm is input, the data comparator 31 compares the pattern data of the previous pattern Pm-1 already stored in the data holding unit 30 with this Pm.
Compare with the pattern data.

■In the data comparator 31, Pm = Pm-
When it is determined to be 1, the control section 32 increments the repeat counter 33 based on the determination result.

In addition, at this time, the same pattern detection unit 34 is made to store the fact that they match (Pm=Pm-1).
When the ring Pm-1 is reached, and when pattern data different from the pattern data one block before is input, the control section 32 determines that the pattern data of the same pattern detection holding section is P.
Determine whether or not m-1■Pm-2, Pm-1-P
When it is determined that it is Pm-2, compressed data is generated from a data pattern sequence of the pattern data of Pm-1 stored in the data holding unit 30 and the count value Rc until the value reaches PmζPm-1 by the repeat counter 33. Part 3
Output to 5.

■The compressed data generation unit 35 generates Pm-1# Pm=1,
Output the compressed data of Rc.

FIG. 2 (&) shows a pattern sequence for explaining the processing of the above pattern data.
7 data is expressed as pA.

0th order, P m "q Pm-1, and the detection signal of the same pattern detection holding section 34 (Pm-IS Pm-2
) is not present, the same pattern data will not be repeated, so the compressed data generating unit 35 outputs the pattern data of Pm-1 stored in the data holding unit 30 as is. FIG. 2(b) shows the pattern sequence at this time, and here it is shown as the pattern sequence 42 when the input pattern data is PB tPc IPD. This is expressed as a parallel pattern string.0 FIG. 3 is a block connection diagram showing another embodiment. 36
37 is an O pattern detection unit that determines whether the input pattern data of Pm is O, and 37 is the previous pattern P.
O to remember that the pattern data of m-1 was 0
This is a pattern detection and holding section. Note that the same components as in FIG. 1 are given the same reference numerals.

Next, a method for processing character image data will be described with reference to this block diagram.

■When the Pm pattern data of the character image is input, 0
The pattern detection unit 36 determines whether the pattern data of Pm is O or not. Here, if pm=0, a 0 pattern detection signal is sent to the 0 pattern detection and holding section 37, and the 0 pattern detection and holding section 37 stores that it is the O pattern.

(2) The data comparator 31 compares the input pattern data of Pm with the pattern data of Pm-1 stored in the data holding section 30.

■When Pm=Pm-1, the control section 32 uses the repeat counter 33 according to the coincidence signal from the data comparator 31.
advance.

■On the other hand, when Pm"qPm-1, K is
2 discriminates the detection signals of the same pattern detection holding unit 34 and the 0 pattern detection holding unit 37, and the same pattern detection holding unit 3
When the coincidence signal of 4 (Pm-1=Pm-2) and the detection signal (Pm-1-〇) from the 0 pattern detection holding unit 37 are both output, the data stored in the data holding unit 30 The pattern data of Pm-1 (-0) and the counter value Rc of the repeat counter 33 are sent to the compressed data generation section 35.

■The compressed data generation section 35 is 0. Output the compressed data of Rc. This compressed data is the pattern string 43 in FIG. 2(C).
0 ■Also, the coincidence signal (pm-1) of the same pattern generator 34
= pm-2) is not detected, and the 0 pattern detection holding unit 3
When the detection signal (Pm=1-0) from 7 is being output, the pattern data of Pm-1 stored in the data holding section 30 and the count value Rc (=1) of the repeat counter 33 up to now are compressed. The data is input to the data generation section 35.

■At this time, the compressed data generation unit 35 outputs 0, Rc (=1
) outputs compressed data.

(2) On the other hand, if the O pattern detection section 36 does not detect the O pattern, the same operation as described in FIG. 1 is performed.

In this way, in another embodiment, when the data pattern of Pm(-0) is repeated Rc times in succession, 0. R
Since data compression is performed with c, there is no compressed data with consecutive 0, 0 in the compressed data string. Then, by inserting the compressed data string KO,0 as a function code, it can be used for various controls when decoding this 0,0.

FIG. 4 shows a specific example of data compression using the present invention. In the figure, 50 is a character image to be output, and 51 is an enlarged view of a part of the character image 50. When the pattern data represented by 8 bits in the Y direction of the character image data 50 to be outputted is sequentially input into the data holding unit 30, the uncompressed pattern string is as shown in FIG.
), whereas the pattern sequence when data is compressed according to the first embodiment is as shown in Fig. 4(b), and when data is compressed according to the other embodiments mentioned above. The pattern row at this time is as shown in FIG. 5(C).

[Effects of the Invention] As explained above, according to the method of the present invention, the following effects can be obtained.

■When the pattern data of Pm is continuous Rc times, Pm
A high data compression rate can be obtained by writing ePm*Rc and writing the rest as t.

■The pattern data of Pm, which is repeated continuously with Pm #Pm#Rc, should be written twice, but there is no need for a special code to indicate continuity.0■No special code is provided. For example, pattern data can be expressed using all bits of the n-bit pattern Pm.

■When the pattern data of Pm=O is repeated Rc times in a row, an even higher data compression rate can be obtained by notating it as O, Rc. Can be used.

Further, according to the apparatus of the present invention, the following effects can be obtained.

■Data compression using the developed F14 eliminates the need to provide storage segments for all pixels that make up a character image, and the circuit is simple, making it possible to reduce the size and cost of the entire storage device, as well as data processing. This improves speed and reduces data transfer time. Thus,
Even a storage device with a small capacity has the effect of being able to obtain high-quality character images.

[Brief explanation of the drawing]

FIG. 1 is a block connection diagram showing one embodiment of an image data processing device according to the present invention, FIG. 2 is an explanatory diagram showing a pattern sequence compressed according to the present invention, and FIG. 3 shows another embodiment. A block connection diagram, FIG. 4 is an explanatory diagram showing an example of data compression of a character image, and FIG. 5 is an explanatory diagram showing a conventional compressed pattern string. 30 is a data holding unit, 31 is a data comparator, 32
3 is a control section, 33 is a repeat counter, 34 is a same pattern detection/holding section, and 35 is a compressed data generation section.

Claims (3)

[Claims] (1) When the pattern Pm constituting this pattern sequence is continuously repeated Rc times for a data pattern sequence of an input character image of n bits (n=1, 2, 3...),
A character image data processing method characterized in that the pattern strings are expressed as Pm, Pm, and Rc, and when the same pattern data Pm is not consecutive, it is expressed as is and data compression is performed. (2) Regarding pattern Pm, when Pm = 0 (a pattern in which all n bits are 0) is repeated Rc times,
2. The character image data processing method according to claim 1, wherein the pattern sequence is expressed as O and Rc to perform data compression. (3) a data holding unit that holds the pattern data of the pattern Pm-1 immediately before the m-th pattern Pm in the pattern string of the character image, and a data comparator that compares the pattern data of Pm and Pm-1; A repeat counter that is incremented when the pattern data of Pm and Pm-1 match, a same pattern detection holding unit that stores that the pattern data of Pm and Pm-1 match, and pattern data of Pm and Pm-1. When the same pattern detection and holding section no longer matches, the detection signal (Pm-1=Pm-
2), and if they match, the pattern data of Pm-1 stored in the data holding unit and the count value Rc so far by the repeat counter are determined, and if they do not match, the pattern data of Pm-1 is determined. A character image data processing device comprising: a control section that outputs only data to a compressed data generation section.