JPH0363885A - Filtering system - Google Patents

Abstract

PURPOSE:To perform filtering with a memory small in capacity without requiring a memory area in a storage area by storing the computed result of a filtering arithmetic means in a picture element area at the part diagonally to upper left of the adjacent area of a remarked picture element. CONSTITUTION:An arithmetic operation is applied on the density value of the rectangular adjacent area 23 of the remarked picture element f(i,j) of an input original image inputted to an input original image area 21 with the filtering arithmetic means, and the computed result can be found. The computed result is stored in the picture element area f(i-1,j-1) at the part diagonally to upper left of the adjacent area of the remarked picture element, and the next remarked picture element is calculated with a next picture element calculation means, and a final picture element judging means judges whether or not a picture element is the final one. When it is the final picture element, the filtering is completed, and when it is not, the filtering arithmetic means, a diagonal upper left storage means, and a raster processing are executed repeatedly. Then, the input original image area 21 and the storage area 22 are formed in such a way that they are deviated by one line vertically and horizontally. In such a way, the filtering can be performed in a small memory area.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a computer system etc. that performs image processing, and particularly relates to an image filtering method.

[Conventional technology]

Conventionally, in filtering, even when there is no need to reprocess the input original image, the input original image area and the storage area for the filtering results are prepared separately in the memory area, and a rectangular neighborhood area of the pixel of interest in the input original image area is stored. A filtering operation is performed on the density value of , and the result of the filter link operation is stored in a storage area. Therefore, a memory area twice the size of the input original image area was required.

[Problem to be solved by the invention]

In the conventional filtering described above, even when there is no need to reprocess the input original image, the input original image area and the storage area for filtering results are prepared separately, so the area is twice as large as the input original image area. The disadvantage is that it requires a memory area of .

[Means to solve the problem]

The filtering method of the present invention includes an original image input means for inputting image data into an incoming original image area, a filtering operation means for performing an operation on a density value within a rectangular neighborhood area of a pixel of interest in an incoming original image, and a filtering operation means for inputting image data into an incoming original image area; upper left storage means for storing the calculation result of the main calculation stage in a pixel area diagonally upper left of the neighborhood area of the pixel of interest, and the filtering calculation means and upper left storage means are performed for all pixels by raster scanning. raster processing means.

〔Example〕

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

FIG. 1 is a flowchart showing one embodiment of the present invention. In the figure, the filtering method includes an original image input means 1 that inputs image data into an incoming original image area, and a calculation is performed on the density value in a rectangular neighborhood area of a pixel of interest in the input original image.
a filtering calculation means 2 for obtaining a calculation result; an upper left storage means 3 for storing the calculation result of the filtering calculation means 2 in a pixel area diagonally above and to the left of the neighborhood area of the pixel of interest;
It comprises a raster processing means 4 which performs the filtering calculation means 2 and left diagonal main output means 3 by raster scanning for all pixels.

FIG. 2 is an explanatory diagram showing an intermediate process of 3×3 filtering.

When filtering is performed, image data is input into the incoming original image area 21 by the original image input means 1. For the pixel of interest f(ij) of the input original image, the filtering calculation means 2 performs a calculation on the density value of the rectangular neighborhood area 23 of the pixel of interest to obtain a calculation result. Then, the upper left storage means 3 stores the calculation result of the filtering calculation means 2 in the upper left pixel area f of the neighborhood area of the pixel of interest.
(Stored in i-1, j-1>.

After storing the calculation results, the next pixel of interest is calculated by the next pixel calculating means 41, and the final pixel determining means 42 determines whether or not it is the final pixel. If the pixel is the final pixel, the filtering is finished, and if the pixel is not the final pixel, the filtering calculation means 2, the upper left storage means 3, and the raster processing 4 are repeated.

As described above, the input original image area 21 and the storage area 22 are shifted by one line vertically and one line horizontally.

〔Effect of the invention〕

As explained above, the present invention stores the calculation result of the filtering calculation means in the pixel area diagonally to the upper left of the neighborhood area of the pixel of interest in filtering that does not require reprocessing of the input original image. This has the effect of not requiring a memory area and allowing filtering to be performed with a small amount of memory.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an embodiment of the filtering method of the present invention, and FIG. 2 is an explanatory diagram showing an intermediate process of filtering processing. DESCRIPTION OF SYMBOLS 1... Original image input means, 2... Filtering calculation means, 3... Upper left storage means, 4... Raster processing means, 21... Incoming original image area, 22... Storage Area, 23... Rectangular neighborhood area.

Claims (1)

[Claims] Original image input means for inputting image data into the input original image area; filtering calculation means for performing calculations on density values within a rectangular neighborhood area of the target pixel of the input original image; It has an upper left storage means for storing data in a pixel area diagonally above and to the left of a neighboring area of a pixel, and a raster processing means that performs the filtering calculation means and the upper left storage means for all pixels by raster scanning. A filtering method characterized by: