JPH0495177A - Image enlargement processing system - Google Patents

Abstract

PURPOSE:To obtain the image data which is smooth by executing a specific picture element correction with respect to an image enlarged to two folds in the horizontal and the vertical directions. CONSTITUTION:A hardware 22 using a data compressing/expanding controller, etc., is used, and is connected to an original image data memory 21 by a system bus 23. In such a state, binary image data is expanded to two folds in the horizontal and the vertical directions, and by taking notice or one line of two continuous lines of the enlarged image data, the left and the right picture elements of a black picture element of the image data are set as black picture elements, and also, as for the black picture element, by performing repeatedly an operation which is not executed at all, binary image data in which the black picture element increase is generated, and moreover, by taking notice of three continuous lines of this image data, only when they are the black picture element and the black picture element, they are set as black picture elements, and in other case, they are set as white picture elements, and by correcting its binary image data, a picture element correction is executed to the image expanded to two folds in the horizontal and the vertical directions. In such a way, the expanded image comes to look smooth.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image enlargement processing method, and particularly to a pixel correction method when enlarging an image twice in the horizontal and vertical directions.

[Conventional technology]

Conventionally, in this type of image enlargement processing, two
When performing double enlargement processing, as shown in FIGS. 4(a) and (b), first, double the bits of that pixel are assigned to each pixel of the original image data A. By doubling the data and writing the data in two consecutive lines, double enlargement processing is realized in the horizontal and vertical directions, and conversion processing is performed to double enlarged image data B.

[Problem to be solved by the invention]

In the conventional double-enlargement processing method in the horizontal and vertical directions described above, each pixel of the original image data is allocated twice as many bits as that pixel in the horizontal direction, and the data is continuously enlarged in the vertical direction. Since the processing is realized by writing in two lines, the image data resulting from the double enlargement process in the horizontal and vertical directions becomes an angular image, which has the disadvantage that the image appears coarse.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image enlargement processing method that eliminates such drawbacks and allows enlarged images to appear smoothly.

[Means to solve the problem]

The configuration of the present invention is to expand the binary image data twice in the horizontal and vertical directions in a binary image image enlargement processing method that doubles the binary image data stored in advance in the horizontal and vertical directions. Then, focusing on one line out of the two consecutive lines of this enlarged image data, the pixels to the left and right of the black pixel in the image data are made black pixels, and the operation is performed to do nothing to the black pixels. By repeating this process, we create binary image data in which the number of black pixels has increased, and then we focus on three consecutive lines in which the number of black pixels in the binary image data has increased, and calculate whether these are black pixels and black pixels. The pixel correction is performed on an image enlarged twice in the horizontal and vertical directions by correcting the binary image data by making the pixel a black pixel only at certain times and a white pixel at other times. .

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a flow diagram illustrating an embodiment of the present invention, and FIGS. 2(a) to 2(d) are plan views of image data illustrating the image processing of FIG. 1 in the order of steps. First, as shown in FIG. 2(a), the original image data A is enlarged twice in the horizontal and vertical directions to create binary image data B as shown in FIG. 2(b'). , focus on two consecutive lines in this image data BO, and increase the number of black pixels for one of them (L+, L2, L,) by making the pixels on the left and right of the black pixel black. Then, a binary image data Bl is created as shown in FIG. 2(c). Furthermore, line L4 where the number of black pixels has increased
．． L6. Focusing on L, compare two lines (L4, I-b) with line L6 as the center, and when the comparison shows black pixels, only black pixels are used, and in other combinations, black pixels are used. This is a method of correcting the image data B1 by changing it to white pixels, and correcting the image to corrected image data B2 as shown in FIG. 2(d).

FIG. 3 is a block diagram of a system to which this embodiment is applied. In this embodiment, the hardware 22 using a data compression/expansion controller or the like is used, and is connected to the original image data memory 21 by a system bus 23. This hardware 22, in step 1.2,
Image data Bo ('Fig. 2(b)), which is twice the horizontal and vertical expansion of the original image data A shown in Fig. 2(a).
Create a file. Based on this created data, in step 3, it is determined which of the two consecutive lines to extract one line, line L1. L2, L5. ), step 4.
In step 5, the pixels to the left and right of the black pixel are made black pixels, and image data B1 with increased number of black pixels is obtained. When the processing of the corresponding line is completed in the next step 6, in step 7, focusing on the 3 consecutive lines where the number of black pixels has increased, mask processing is performed with the lines above and below, focusing on the 2nd line of the 3 consecutive lines. (logical product) is performed, and line correction is performed in which only when the combination is a black pixel and a black pixel, the pixel is treated as a black pixel, and in other cases, it is treated as a white pixel, thereby obtaining corrected image data B2. Here, line L9 in FIG. 2(d) masks lines L4 and L6 in FIG. 2(C), and line L11 masks line L6. Line L7 is subjected to mask processing, line L1o is obtained by masking lines L, .

In this way, it is possible to obtain more smoothed image data even for image data enlarged twice in the horizontal and vertical directions.

Although this embodiment shows the case of the hardware 22, a CPU can also be used instead of the hardware 22. When a program written by a software algorithm is loaded, this CPLI sequentially reads the original image data (21), converts the data according to the algorithm, and smoothes the data by double enlargement in the horizontal and vertical directions. All you have to do is convert it to image data.

〔Effect of the invention〕

As explained above, according to the pixel correction method of the present invention, it is possible to obtain more smoothed image data for image data enlarged twice in the horizontal and vertical directions.

22...Hardware, 23...System bus, A...Original image data, B, Bo...2x enlarged image data in the horizontal and vertical directions, B1 Yamaguro pixel additional data, B2. ...Corrected image data, L1-L, ...Line to which black pixels are added, L4, L6, L, s...
・Correction line.

Claims (1)

[Claims] In a binary image image enlargement processing method that enlarges pre-stored binary image data twice in the horizontal and vertical directions, the binary image data is enlarged twice in the horizontal and vertical directions, and the enlarged image is Focusing on one line out of two consecutive lines of data, the pixels to the left and right of the black pixel in the image data are set as black pixels, and the operation of doing nothing to the black pixels is repeated until the black pixel is Create binary image data with increased black pixels, and then focus on three consecutive lines with increased black pixels in the binary image data with increased black pixels, and only when these are black pixels, consider them as black pixels. An image enlargement processing method characterized in that pixel correction is performed on an image that has been enlarged twice in the horizontal and vertical directions by correcting the binary image data so that pixels are white at other times.