JPH0594522A - Image reduction processing system - Google Patents

Abstract

PURPOSE:To execute an image reduction without degrading the quality of a reduced image by means of simple image processing prevented from the increment of cost. CONSTITUTION:This image reduction processing system is provided with a dot information judging processing means 1 for judging the number of black dots in image data, thinning reduction processing means 2 for executing thinning processing and an n-dot OR reduction processing means 3. When there are black dot data >=2 dots at the time of checking the number of black dots out of 2n dots in the image data in the main scanning/subscanning direction, 1/n thinning reduction processing is executed, and when the black dot data of only one dot exist, n-dot OR reduction processing is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a print output device,
The present invention relates to an image reduction processing method in a monitor output device or the like.

[0002]

2. Description of the Related Art Conventionally, in image reduction in a copying machine or the like, a thinning reduction process of sampling image input data with a clock signal having a cycle corresponding to the degree of reduction and thinning it out, and taking an OR between adjacent dots to eliminate black dots. Adjacent dot OR processing for reducing data so as not to perform, and area pattern conversion reduction processing for performing area conversion on the pattern of image input data to perform reduction conversion are performed.

[0003]

The thinning reduction processing is adopted in a general image processing apparatus and has an advantage that the processing is very simple. However, only the dot data is thinned out. However, although the reduced image is neat, the line having a 1-dot width disappears, and it may not be possible to discriminate the character even if the character has a small number of dots. Further, in the reduction process for taking the OR between the adjacent dots, the black dot data is always utilized, so that the black dots are not lost, but on the contrary, the line becomes thick or the characters become solid black and are crushed, and the reduced image The quality is reduced. Further, the area pattern conversion / reduction processing is currently adopted in high-end machines, and although a high-quality reduced image can be obtained, the pattern storage capacity becomes extremely large and the processing is difficult, resulting in an increase in cost. There is a problem of leaving.

In a general class of copying machines, printers, etc., the dot configuration of the built-in font is small and the processing speed is relatively slow, so complicated image reduction processing cannot be performed and the quality of the reduced output image deteriorates. There was a drawback that it would end up. The present invention is to solve the above problems, and an object of the present invention is to provide an image reduction processing method capable of performing image reduction without degrading the quality of a reduced image by simple image processing that does not increase cost. And

[0005]

According to the present invention, in an image data processing system for reducing input image data in a main scanning direction and / or a sub-scanning direction and outputting the same, a dot for determining the number of black dots in the image data. Information discrimination processing means, thinning reduction processing means for performing thinning processing, and n (n
= 2, 3 ...) Dot OR reduction processing means, and one of the thinning reduction processing means and the n dot OR reduction processing means is selected according to the number of black dots to perform reduction processing. To do. In addition, the thinning reduction processing unit is 2
When the number of black dots in n dots is 2 or more, 1 / n reduction processing is performed, and when the number of black dots in 2n dots is 1, 1 / n reduction processing is performed by n dot OR. It is characterized by performing.

[0006]

According to the present invention, the number of dots in 2n dots of the image data in the main scanning direction and / or the sub scanning direction is checked,
1 / n when there is 2 or more "black" dot data
When thinning reduction processing is performed to obtain 2 dot data, if only 1 dot has "black" dot data, n dot O
The 1 / n image reduction process is performed by performing the R reduction process and obtaining the data of 2 dots of "black" and "white". In the case of thinning reduction processing, since there are two or more "black" dots in the input image data, it is unlikely that a "black" dot will be missing, and because there is only one "black" dot data, a dot will be missing. If there is a possibility that
Since the “black” dots are utilized by the reduction processing, it is possible to improve the reduced image quality by simple image processing.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a functional block diagram of the present invention, FIG. 2 is a diagram showing a hardware configuration of the present invention, FIG. 3 is a diagram for explaining 1/2 thinning and reduction processing, and FIG. FIG. 5 is a diagram for explaining a dot OR, and FIG. 5 is a 2 dot O of 4 dots.
FIG. 6 is a diagram illustrating a logic circuit for realizing R reduction processing, FIG. 6 is a diagram showing a reduction processing flow of the present invention, FIG. 7 is a diagram showing a configuration of a print output device, and FIG. 8 is a diagram showing a configuration of a monitor output device. is there. In the figure, 1 is dot information discrimination processing means, 2 is thinning reduction processing means, 3 is n dot OR reduction processing means, 10 is CPU, 10a is dot information discrimination processing part, 10b is thinning reduction processing part, and 10c is n dot. OR reduction processing unit, 11
Is a main memory, 11a is image data, 12 is an output device, 1
Reference numeral 3 is an input device, and 14 is an external storage device.

In FIG. 1, dot information discrimination processing means 1
, For example, takes in image data for each 2n (n = 2, 3 ...) Dots and determines how many black dots are in the 2n dot data. When the number of black dots is two or more as a result of the discrimination processing, the thinning reduction processing unit 2
Data of 2 dots is obtained by simply performing 1 / n thinning reduction processing for extracting data at a rate of one for every n. When the number of black dots in the 2n-dot data is one, the n-dot OR reduction processing means 3 performs the reduction processing for extracting the 2-dot data by utilizing the black dot data. Although 1 / n image reduction is performed in this way, in the case of thinning reduction processing, since there are two or more "black" dot data in the input image data, it is less likely that "black" dots will be missing, and "black" dots will not occur. When there is a possibility that one dot data is missing and a dot is missing, the “black” dot is utilized by the n-dot OR reduction process, and thus it is possible to improve the reduced image quality.

Such a reduction process is realized by the hardware configuration shown in FIG. 2, and the CPU 10 has the external storage device 14
The dot information discrimination processing unit 10a and the thinning reduction processing units 10b, n each including each module of the program read from
The dot OR reduction processing unit 10c performs reduction processing of the image data 11a stored in the main memory 11, and the bus 15
Through the output device 12.

Next, the 1/2 reduction processing will be described as an example with reference to FIGS. The 1/2 thinning-down processing is shown in FIG.
As shown in (a), the image data is fetched in units of four dots, and this is performed when two or more black dots are included in the image data, and two dots are simply extracted from the black dots. That is, as shown in FIG. 3B, the image data is sampled with a clock having a cycle twice that of the image data, so that the thinning-out reduction is performed. Since two or more black dots are included in the four dots of the image data, black dots are less likely to be missing from the reduced image data.

In the 4-dot 2-dot OR reduction process, as shown in FIG. 4, 4-dot image data (A,
When only one dot of B, C, D) has black data, 2-dot data (α, β) is output. For example, (1, 0, 0, 0), (0, 1, 0) , 0), (1, 0) is output as (α, β), and (0,
In the case of 0,1,0) and (0,0,0,1), (α,
β) (0, 1) is output. This 4 dots 2 dots O
The R reduction processing can also be realized by a logic circuit as shown in FIG. 5, for example. First, as shown in FIG. 5A, it is determined whether or not only one dot out of four dots is black data.
Four AND circuits 5 each having four dot data (A, B, C, D) input thereto and having three negative logic gates
1 to 54, OR circuit 55 to which the output of each AND circuit is input
It is realized by a logic circuit consisting of. That is, if there is black data for only one dot in the 4-dot data (A, B, C, D), one of the outputs of the AND circuits 51 to 54 becomes "1" and the output of the OR circuit 55 becomes Since it is "1" and the output of the OR circuit 55 is "0" in other cases, only one dot out of four dots is black data depending on whether the output of the OR circuit 55 is "1" or "0". It is determined whether or not. Further, when only one of the four dots is black data, the two-dot OR reduction process of four dots is performed as shown in FIG.
As shown in (b), four D flip-flops (D-F / F) 61 to 64 and image outputs (A, OR circuit 65 to which B) is input, DF / F6
This can be realized by the OR circuit 66 to which the outputs (C, D) of 3, 64 are input. That is, the outputs (A, B, C, D) of the D-F / Fs 61 to 64 are any one of to in FIG. 4, and “α” is output from the OR circuit 65 and “β” is output from the OR circuit 66. In the case of ,, (1,0) ,,
In the case of, (0, 1) will be output. In the 2-dot OR reduction process of 4 dots, even if there is only one black dot, it is utilized, so black dots are less likely to be lost, and the reduced image quality of lines and characters can be improved.

FIG. 6 is a 1 / n reduction processing flow in the image reduction processing method of the present invention. First, 2n dot data is fetched in the main scanning direction, and it is judged whether or not only 1 dot in the 2n dot data is a black dot. If only 1 dot is a black dot, the n dot OR reduction processing as described above is performed. If there are two or more black dots, the above-described thinning reduction processing is performed (steps 100 to 10).
2). Similarly, the same process is performed for 2n dots in the sub-scanning direction to obtain 1 / n in the main scanning direction and the sub-scanning direction.
Image reduction can be performed.

FIG. 7 shows the construction of a print output device which employs the image reduction processing system of the present invention. The CPU 20 reads the control program from the ROM 21 by operating the control panel 26, and drives the driver 30 and the thermal printer head 31 based on the data loaded in the RAM 22 and the character data in the font ROM 23 to print on the paper supplied by the motor 29. The image reduction processing is performed on the image data read from the data input device 24 via the receiver 25, and the reduced image is output from the thermal printer head 31. By the reduction processing described above, the image can be reduced without deteriorating the quality even if the number of dots of the font contained in the ROM 23 is small.

FIG. 8 shows a case where the image reducing system of the present invention is applied to a monitor output device. The image data is reduced as in the case of FIG. 7, and high-quality reduced image data is displayed on the LCD 41 via the driver 40. It is possible to

[0015]

As described above, according to the present invention, the thinning reduction processing and the n-dot OR reduction processing are combined, and even a straight line of 1 dot width of the original image is less likely to be lost after the reduction processing, and a font with a small number of dots is used. Even with characters, the intelligibility after image reduction processing hardly deteriorates, and high-quality image reduction can be performed.

[Brief description of drawings]

FIG. 1 is a functional block diagram of the present invention.

FIG. 2 is a diagram showing a hardware configuration of the present invention.

FIG. 3 is a diagram for explaining 1/2 thinning-out reduction processing.

FIG. 4 is a diagram illustrating a 2-dot OR of 4-dots.

FIG. 5 is a diagram for explaining a 4-dot 2-dot OR logic circuit.

FIG. 6 is a diagram showing a reduction processing flow of the present invention.

FIG. 7 is a diagram showing a configuration of a print output device.

FIG. 8 is a diagram showing a configuration of a monitor output device.

[Explanation of symbols]

1 ... Dot information discrimination processing means, 2 ... Thinning reduction processing means, 3 ... n dot OR reduction processing means, 10 ... CPU, 1
0a ... Dot information discrimination processing unit, 10b ... Thinning reduction processing unit, 10c ... n dot OR reduction processing unit, 11 ... Main memory, 11a ... Image data, 12 ... Output device, 13 ... Input device, 14 ... External storage device.

Claims (2)

[Claims] 1. An image data processing method for reducing input image data in a main scanning direction and / or a sub-scanning direction and outputting the same, and a dot information discrimination processing means for discriminating the number of black dots in the image data, and a thinning process. And thinning reduction processing means and n (n = 2, 3 ...) Dot OR
An image reduction processing method, comprising: reduction processing means, wherein one of the thinning reduction processing means and the n-dot OR reduction processing means is selected and reduced according to the number of black dots. 2. The thinning reduction processing means performs 1 / n reduction processing when the number of black dots in 2n dots is 2 or more, and the n-dot OR reduction processing means reduces the number of black dots in 2n dots to 1.
An image reduction processing method characterized in that 1 / n reduction processing is performed by n-dot OR at the time of each piece.