JPS61211778A - Data storing system - Google Patents

Abstract

PURPOSE:To reduce the number of accesses by making a data storing an area capable of making access at one time on a memory area rectangular areas divided on a two-dimensional data. CONSTITUTION:After all data are stored in a memory area from a facsimile equipment 1, a central processing unit 2 divides the image data of the memory area 4 into rectangular areas and the respective rectangular areas are moved to the memory area as one word. Under a condition in which the image data is stored, in case of making access to a small region of 3X3 and a center of the 3X3 matrix is situated in a position of A, the accesses of 4 words of a word corresponding to the rectangular area in which a center point exists, and three words corresponding to adjacent three rectangular areas respectively are required. When the center is situated in the position of B, the accesses of two words of a word corresponding to the rectangular area in which a center point is situated and a word corresponding to an upper or a lower or a right or a left rectangular area of the rectangular area are required. When the center is situated in a position of C, only a word corresponding to the rectangular area in which the center point is situated may be made access. Thereby, an average number of the access words is drastically decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data storage method for storing two-dimensional data such as image data in a one-dimensional storage area.

〔overview〕

When storing two-dimensional data such as image data in a one-dimensional storage area, it is a data storage method that allows efficient extraction of features of figures, for example, by storing it in appropriately divided rectangular areas. .

[Conventional technology and problems]

For example, when interpreting binary black and white image data read by a fax machine using a computer, it is necessary to extract various features of the image. Features of an image mean, for example, where a line ends and where a line branches. To do this, it is necessary to track black pixels or white pixels on the image data, and to do so, it is necessary to trace a rectangular area (for example, 3 x 3) centered on the black pixel or white pixel.
pixel values are required.

FIG. 4 is a diagram for explaining pixel tracing. To trace a black pixel from a point (black pixel), check the pixels in a 3 x 3 area centered on that point, and if there is a black pixel outside the point board, move that black pixel to the next center. Repeat the operation as follows. In the illustrated example, the black pixel to the right or diagonally lower left of the current center point becomes the next center point. however,
The center point before the current center point is not used as the next center point.

FIG. 5 is a diagram for explaining a conventional data storage method. In conventional technology, image data is
When storing dimensional data, one line (1, I'NEn
For example, each row is divided into 32-bit units, and each division is stored in the main memory as one word. In the illustrated example, the 0th section (leading section) of the 0th line (leading line) of the rod is stored at the 0th address of the above 1.a, and the 1st section of the 0th line is stored at the 1. a
is stored at the first address.

FIG. 6 is a diagram for explaining the average number of access words when accessing a 3×3 small area under the state in which image data is stored as shown in FIG. 5. As shown in A, if both ends of one word are the center of a 3x3 matrix, there are two words: a word with a center point, a word with points located above and below the center point, and a word with points located next to the center point. It is necessary to access a total of six words 1-, including the word in which the point exists and the word in which the point located above and below the adjacent point exists. As shown in B, the middle of one word is 3×
In the case of the center of three matrices, it is necessary to access a total of three words: the word where the center point exists and the word where the points located above and below the center point exist. Therefore, the average number of accessed words is (6x2+3x30) ÷32 = 102
÷32, and the average number of accessed words is relatively large.

[Purpose of the invention]

The present invention is based on the above consideration, and an object of the present invention is to provide a data storage method that can reduce the number of accesses when accessing two-dimensional data (for example, pixel data) in a small area of nXn. It is a feature.

[Means to achieve the purpose]

The data storage method stores two-dimensional data such as image data in a one-dimensional storage area such as the main memory of a computer, and the data storage method stores two-dimensional data such as image data in a one-dimensional storage area such as the main memory of a computer. The feature is that the data is divided into rectangular areas.

[Embodiments of the invention]

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

FIG. 1 is a diagram for explaining one embodiment of the present invention.

In the present invention, as shown in FIG.
Divide into rectangular areas of bit x 4 lines, and each rectangular area
Stored in main memory as a word. In the illustrated example, bits O to 7 of the 0th line, hits 0 to 7 of the first line, focus O to 7 of the second line, and bits O to 7 of the third line are stored at address 0 of the main memory. , bits 8 to 15 of the 0th line, focus 8 to 15 of the first line, bits 8 to 15 of the second line, and bits 8 to 15 of the third line are stored at the first address of the main memory.

FIG. 2 is a diagram for explaining the average number of access words when a 3×3 small area is accessed under the state in which image data is stored as shown in FIG. 1. If the center of the 3x3 matrix is at position A, a word corresponding to the rectangular area where the center point exists, and 3 words corresponding to each of the three rectangular areas adjacent to the rectangular area, in total. 4 word access is required. 3×
3. When the center of the matrix is at position B, a word corresponding to the rectangular area where the center point exists and one word corresponding to the rectangular area above or below or to the right or left of the rectangular area, a total of 2 words. access is required. If the center of the 3×3 matrix is at position C, only the word corresponding to the rectangular area where the center point exists needs to be accessed. Therefore, the average number of access words is (4 x 4 + 2 cross 16 + 1 x 12) ÷ 32
= 60÷32, and the average number of access words is significantly reduced compared to the conventional method.

FIG. 3 is a diagram showing one application example of the present invention. In FIG. 3, ■ indicates a facsimile machine, 2 indicates a central processing unit, 3 indicates a main memory, and 4 and 5 indicate storage areas, respectively. The central processing unit 2 stores the data sent from the facsimile machine 1 in the storage area 4 in the manner shown in FIG. After storing all the data from the facsimile machine I in the storage area 4, the central processing unit 2 transfers the data in the storage area 4 to the storage area 5 in the manner shown in FIG.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, when accessing image data of a small area of nXn on a screen, the number of accesses required can be significantly reduced compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining one embodiment of the present invention, and FIG. 2 is a diagram showing a case where a 3×3 small area is accessed under the state in which image data is stored as shown in FIG. 1. Figure 3 is a diagram for explaining the average number of access words, Figure 3 is a diagram showing an example of application of the present invention, Figure 4 is a diagram for explaining pixel tracing, and Figure 5 is a diagram for explaining the conventional data storage method. FIG. 6 is a diagram for explaining the average number of access words when accessing a 3×3 small area under the condition that image data is stored as shown in FIG. 5. It is. 1...Facsimile machine, 2...Central processing unit, 3
...Main memory, 4 and 5...Storage area.

Claims (1)

[Claims] In a data storage method that stores two-dimensional data such as image data in a one-dimensional storage area such as the main memory of a computer, the data to be stored in an area that can be accessed at one time on the storage area is divided into rectangles on the two-dimensional data. A data storage method characterized by using an area.