KR19980041599A - Binarization Method and Apparatus - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs

The present invention relates to a method and apparatus for black and white binarization of multi-gradation images.

I. The technical problem that the invention is trying to solve

Quickly and simply binarize the + pattern and moire effects that appear regularly.

All. Summary of Solution of the Invention

A counter for generating position information of the original image, an index generation unit for receiving an gradation value of the original image, generating an index corresponding to the gradation value of the original image, and a position for generating position information corresponding to the output of the counter An information generator and a plurality of binary patterns optimized for a visual model on a plurality of pages, wherein the index and the page correspond to each other, and the binary pattern and the location information correspond to the index and the location information. A binary pattern page set unit for outputting a binary pattern of a page corresponding to the location information, a repeating point replacement unit for outputting a binarized value after performing iterative replacement to prevent deterioration of an image composed of binarized values, and Binary pattern The binary pattern output from the page set unit and the previous value in the binary image are input. And, it characterized by comprising a comparison output to a binarizing equal value.

la. Important uses of the invention

It is used in the apparatus for outputting multi-gradation images.

Description

Binarization Method and Apparatus

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for outputting a multi-gradation image by black and white binarization in an image output apparatus.

In general, there are two conventional methods for black and white binarizing a multi-gradation image.

The first method is to construct an array containing a reference value of a certain size, quantize the original image, and compare it with the value of the reference value array at the position corresponding to the value, and binarize it to white when it is small and white when it is large. At this time, a large difference occurs in the quality of the binarized image depending on the values constituting the array of reference values. The binarized image generated by the conventional technique exhibits a + type pattern effect and a moire effect that occur regularly according to the size of the reference value array, which serves to deteriorate the image quality.

If the error diffusion method is used as a binarization method, it has a good effect on image quality improvement, but the processing for generating and spreading the error is complicated, and the processing speed is slow.

As described above, the conventional binarization method has a + type pattern effect and a moire effect. To avoid this, the error diffusion method has the disadvantage of slowing down the processing speed.

Accordingly, an object of the present invention is to provide a binarization method and apparatus for eliminating + type pattern effects and moire phenomena, and improving complexity and processing speed.

1 is a block diagram of a conventional facsimile;

2 is a flowchart of a binarization method according to a preferred embodiment of the present invention;

3 is a block diagram of a binarization apparatus according to a preferred embodiment of the present invention.

According to an aspect of the present invention, there is provided a counter for generating position information of an original image, an index generation unit for receiving a gray scale value of an original image and generating an index corresponding to the gray scale value of the original image, A location information generation unit for generating location information corresponding to the output, and a plurality of binary patterns optimized for a visual model on a plurality of pages, wherein the index and page correspond to each other, and the binary patterns and location information correspond to the Binary pattern page aggregation unit for outputting a binary pattern of a page corresponding to the index and position information when index and position information are input, and binarized value after performing iterative replacement to prevent deterioration of an image composed of binarized values. Iterate point replacement unit for outputting a binary pattern, and the binary pattern output from the binary pattern page set unit receives the previous value in the binary image Side compared to the input binary pattern to repeat point replacer, and the output is equal to the binarized value is characterized by comprising a.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the annexed drawings, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

1 is a block diagram of a conventional facsimile, and the controller 10 controls the overall operation of the facsimile according to a set program. In addition, the controller 10 may have a program memory and data in which a memory is built-in or externally connected.

A program according to the present invention is stored in the program memory, and data generated during program execution is temporarily stored in the data memory. The operation panel 12 is composed of key input means and display means. The key input means of the operation panel 12 provides the control unit 10 with key input data that the user presses to designate each mode and perform an operation of the designated mode. In addition, the display means of the operation panel 12 performs a function of inputting and displaying display data indicating an operation state of the system from the control unit 10. The sensor unit 14 detects the presence or absence of input of a document and the presence of print paper, and outputs the detected state signal to the control unit 10. The scanner 16 moves an input document, scans an image of the document, and converts the image into digital data. The image processing unit 18 processes and outputs an image signal output to the scanner 16 in a transmission mode and a copy mode under the control of the control unit 10, and processes an image signal received through a transmission line in a reception mode. . The image processing unit 18 encodes the image data output from the scanner 16 according to the standard of the facsimile, and decodes the image data encoded and received into the original image data. The print processor 20 prints image data input from the image processor 18 on a print sheet when the reception mode and the copy mode are executed under the control of the controller 10. The modem 22 modulates and transmits the image data output from the image processing unit 18 in a transmission mode under the control of the control unit 10 into an image signal in a transmission mode, and transmits the image signal input in the reception mode. Demodulate to process at (18). The network control unit (NCU) 24 forms a transmission / reception path between the telephone line and the modem 22 under the control of the control unit 10.

According to the present invention, the control unit 10 may include a program according to a binarization method, or may include a binarization device separately.

First, the binarization method will be described in detail with reference to FIG. 2, which shows a flowchart of the binarization method according to a preferred embodiment of the present invention.

In step 26 of FIG. 2, the controller 10 quantizes image data input from the scanner 16. When the quantization ends, the controller 10 performs step 28. In step (28), the controller 10 sets the gray level value of the image according to the quantization as an index. When the setting of the index is completed, the controller 10 performs step 30. In step 30, the controller 10 reads a binary pattern corresponding to the index from a set of binary pattern pages.

The binary pattern page set is composed of visual model optimized values for each gray level value, and the size of one page is not limited.

When the read of the binary pattern ends, the controller 10 performs step 32. In step (32), the control unit 10 reads the previous value in the binary image. When the read ends, the controller 10 performs step 34. In step 34, the controller 10 searches whether the binary pattern and the previous value in the binary image are different. At this time, the controller 10 performs step (36) if the binary pattern and the previous value in the binary image are different, and performs step (38) if the same. In step (36), the controller 10 performs overlapping point replacement. When the overlapping point replacement is completed, the controller 10 performs step 38. In step 38, the control unit 10 performs marking and ends.

The binarizing device will now be described in detail with reference to FIG. 3, which shows a block diagram of the binarizing device according to a preferred embodiment of the present invention.

The count value of the counter 40 in FIG. 3 is used as position information of the original image. The index generator 42 receives the grayscale value of the original image and generates an index. The location information generation unit 44 generates location information corresponding to the output of the counter 40. The binary pattern page set unit 46 represents each gray value as a binary pattern, and is optimized for each visual model. In addition, the binary pattern page set unit 46 corresponds to the index and the page, and the binary pattern and the location information correspond to each other. When the index and the location information are input, the binary pattern page set unit 46 converts the binary pattern of the page corresponding to the index and the location information. Output The comparator 48 receives the binary pattern output from the binary pattern page set unit 46 and the previous value in the binary image and inputs the binary pattern to the repeating point replacement unit 50 if they are different, and outputs the binary value if the same is different. To switch the switch (SW). The repeating point replacement unit 50 outputs the binarized value after performing the iterative substitution in order to prevent deterioration of the image composed of the binarized values.

As described above, the present invention has the advantage of simple and quick binarization while removing the + type pattern effect and the moire effect that appear regularly.

Claims (2)

In the binarization method, A quantization step of outputting a gray value for quantizing the original image, An index and position information reading step of reading an index and position information corresponding to the gray scale value; A binary pattern reading step of reading a binary pattern of a set of binary pattern pages corresponding to the index and position information; A previous value reading step of reading a previous value in the binary image; A duplicate point substitution step of performing overlapping point substitution if the previous value in the binary pattern and the binary image are not the same; And a marking step of marking a binary pattern equal to a previous value in the binary image or a binary value substituted with a overlapping point. In the binarization device, A counter for generating position information of the original image, An index generator which receives the gray scale value of the original image and generates an index corresponding to the gray scale value of the original image, A position information generator for generating position information corresponding to the output of the counter; A plurality of pages are provided with a plurality of binary patterns optimized for a visual model, and the index and the page correspond to each other, and the binary pattern and the location information correspond to each other. When the index and the location information are inputted, the pages correspond to the index and the location information. A binary pattern page set unit for outputting a binary pattern of a page, a repeating point replacement unit for outputting a binarized value after performing iterative replacement to prevent deterioration of an image composed of binarized values, And a comparison unit for receiving a binary pattern output from the binary pattern page set unit and a previous value in a binary image, and inputting a binary pattern to a repeating point substitution unit if different from each other, and outputting the binary pattern as a binarized value. .