JPH0449473A - Image interpolating and contracting system - Google Patents

Abstract

PURPOSE:To shorten a processing time by providing the image interpolating/ contracting system with plural methods for obtaining respective interpolated results by using the data of one point, the data of two adjacent points in the X direction, the data of two adjacent points in the Y direction, and the data of four adjacent points. CONSTITUTION:The 1st method for obtaining an interpolated result by using the data of one point is applied to A00 and the 2nd method for obtaining an interpolated result by using the data of two adjacent points in the X direction is applied to A01. The 3rd method for obtaining an interpolated result by using the data of two adjacent points in the Y direction is applied to A10, and the 4th method for obtaining an interpolated result by using four adjacent points is applied to A11 and interpolation is repeated. The image obtained by the above methods is contracted from the image data of nine points to the image of four points, i.e. 2/3. Thus, the processing time can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for interpolating and reducing multi-tone image data to 2/3.

[Conventional technology]

FIG. 3 shows an example of a conventional method for interpolating and reducing multi-gradation image data to 2/3. As shown in the figure, all interpolation results were obtained using data from four adjacent points. In other words, Ri. O+ D 0+ + D 10I)tt's 4
Obtain interpolated data for one point from point data, and do the same in the same way as DO
Obtaining one point of interpolated data from four points of data I, DO2, D II+DI2 is repeated.

Do it like this. Four points of interpolated data are obtained from nine points of data from 0 to D22. Three additions and one division are required to obtain one point of interpolated data.

[Problem to be solved by the invention]

In the conventional 2/3 interpolation reduction method described above, two input lines and two column data are required to obtain one interpolation result, so it is necessary to interpolate and reduce the image bone data to 2/3. The disadvantage is that it takes a long processing time.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image interpolation reduction method that partially employs a simple interpolation method to eliminate the above drawbacks.

[Means to solve the problem]

The image interpolation reduction method of the present invention converts multi-tone image data into 2/
In a device that performs interpolation and reduction in size, there are two methods: a first method that uses data from one point to generate an interpolation result, a second method that uses data from two adjacent points in the X direction to generate an interpolation result, and a second method that uses data from two adjacent points in the X direction to generate an interpolation result. A third method uses data from two adjacent points to generate an interpolation result, and a fourth method uses data from four adjacent points to generate an interpolation result. Then, the reduction result is obtained by repeating the first and second interpolation methods, and the third and fourth interpolation methods are used for the subsequent second output line.
The reduction result is obtained by repeating the interpolation method, and the interpolation is then repeated line by line.

Further, the image interpolation reduction method of the present invention obtains a reduction result by repeating the first and third interpolation methods for the first output line, and obtains the reduction result by repeating the first and third interpolation methods for the second output line. The reduction result is obtained by repeating the second and fourth interpolation methods, and thereafter the interpolation is repeated line by line.

〔Example〕

The present invention will be explained below with reference to the drawings.

FIG. 1 is an explanatory diagram showing an embodiment of the interpolation reduction method of the present invention, and shows an example of application to two-dimensional image data. FIG. 2 is an explanatory diagram showing the reduced image.

In Figure 1. 01 DOI+ DO2... each indicates one image data, and A OO+ in Fig. 2
AO+... is image data as a result of reduction.

Next, the image reduction operation according to the present invention will be explained. First, for Aoo, the first method of using one point of data as an interpolation result is applied, and A 00 = D 60 (1). For A 6 l, the second method is applied to obtain the interpolation result using the data of two points adjacent in the X direction, and A o1= (1) ot+D 02) / 2- (
2). Thereafter, the interpolation of A 02-- D 03 A a3-(Do4+Dos)/2 is repeated.

Next, for Alo, a third method is used that uses the data of two points adjacent in the Y direction to obtain the interpolation result, and A +o-(
Determined as D to + D 20) / 2- (3),
For All, a fourth method is used that uses the data of four adjacent points to obtain the interpolation result, and A++-" (D+++D+
2-tD2++D22)/4...(4). Hereafter A I2- (D 13+ D 23)/2A13-
Repeat the interpolation of (DI4+DI5+D24+D25)/4. The image obtained in this way is 4 from the 9 points of image data.
It is reduced to a point image, ie, reduced to 2/3.

Next, thinking about the amount of calculation, Doo, D01+
When calculating AOO+A(11, A 10.
), the reduction is completed by one addition and one division, and the formula (4) is three additions and one division, for a total of five additions and three divisions.

In the conventional method, the calculation amount for each of the four points AOO to A11 requires three additions and one division, for a total of 12 additions and four divisions.

[Effects of the Invention] As is clear from the above explanation, according to the image interpolation reduction method of the present invention, by partially adopting a simple interpolation method,
The effect of shortening processing time can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a reduction result, and FIG. 3 is an explanatory diagram showing a conventional example. D 00 to D 55”' Original image data, A oo
~A33... Image data as a result of reduction.

Claims (1)

[Claims] 1. In an apparatus for interpolating and reducing multi-gradation image data to 2/3, a first method uses one point of data to obtain an interpolation result, and a first method uses two points adjacent in the X direction. A second method uses data to generate an interpolation result, a third method uses data from two adjacent points in the Y direction to generate an interpolation result, and a third method uses data from four adjacent points to generate an interpolation result. A reduction result is obtained by repeating the first and second interpolation methods for the first output line, and the third and second interpolation methods are performed for the subsequent second output line. An image interpolation reduction method characterized in that a reduction result is obtained by repeating the fourth interpolation method, and thereafter interpolation is repeated line by line. 2. In the image interpolation reduction method according to claim 1, the reduction result is obtained by repeating the first and third interpolation methods for the first output line, and the reduction result is obtained for the subsequent second output line. An image interpolation reduction method characterized in that a reduction result is obtained by repeating the second and fourth interpolation methods, and thereafter interpolation is repeated line by line.