JPS61264482A - Picture converting system - Google Patents

Abstract

PURPOSE:To increase the picture converting speed and to improve the flexibility against the change of the conversion algorithm, by using a read-only memory ROM, etc. for picture conversion. CONSTITUTION:The coordinates (X, Y) of a point (b) and conversion magnification ratios alpha and beta of a picture B obtained after conversion are supplied to ROMs 1-3. The ROM 1 delivers the (x) coordinates xk of a reference picture element akl, and the ROM 2 delivers the (y) coordinates yl of the element akl. While the ROM 3 delivers a logical arithmetic mode g5. Then both coordinates xk and yl are supplied to a memory 4 to deliver a picture element ak(l+1) shifted in the direction (y) by a step, a picture element a(k+1)l shifted in the direction (x) by a step and a picture element a(k+1)(l+1) shifted in both directions (x) and (y) by a step respectively. These picture elements are stored in registers 5-1-5-4 respectively. When four reference picture elements are obtained, a gate circuit 6 at the preceding stage of a ROM 7 is opened to supply the reference picture element value and the logical arithmetic mode to the ROM 7. Then the ROM 7 delivers the value of a converted picture element (b).

Description

DETAILED DESCRIPTION OF THE INVENTION [Description of the Field to which the Invention Pertains] The present invention relates to a screen conversion processing method for converting one screen size.

[Description of conventional technology]

Conventionally, this type of conversion processing has been performed using (1) wired logic, (2) microprograms, or the like. However, while the wired logic method achieves high-speed screen conversion processing, it does.

It is necessary to change the hardware in order to change the screen conversion ratio or change the logical operation for conversion.

The drawback is that it is not flexible. On the other hand, in the microprogram-based method, changes in the one-screen conversion ratio, conversion logic operations, etc. can be handled by changing the microprogram without changing the hardware. However, because it is controlled by a microprogram, the conversion process is slow.

[Purpose of the invention]

In order to solve these drawbacks, the present invention uses a memory such as a read-only memory to perform screen conversion processing, thereby increasing the speed and flexibility of two-screen conversion processing, and will be described in detail below with reference to the drawings.

[Description of the structure and operation of the invention]

Consider the screen conversion shown in FIG. 2 in which the conversion magnification in the X direction is α and the conversion magnification in the Y direction is β. In FIG. 2, A is the screen before conversion, and B is the screen after conversion.

In addition, + aII”'a 工 indicates the pixel of screen A + (X
t+y I) ~ (xa, )'m) is pixel al17
This is the coordinate value of an+a.

Now, consider the operation of outputting the pixel value of the coordinate values (X, Y) of screen B after conversion. As shown in Figure 3, when two screens B are mapped onto screen A, the coordinate value of one pixel is (X/α
, Y/β). Next, a pixel on screen A near the coordinates (X/α, Y/β) is selected. The selection method differs depending on the conversion algorithm, but here the coordinates (X/α, Y/β)
Let us refer to the four pixels surrounding . These reference pixels are a kLn a k (L+ll+ a
(k, l) L+ a (k*I) (Li2),
The coordinates are (Xk, )'L)+ (xi++)'
c++ )+ (Xyo+1+ 'J L L (x,,
,,,'/LSI). This reference pixel is uniquely determined once the pixel coordinates after conversion and the conversion magnification in the X direction and the y direction are determined.

Next, the reference pixels akLr ak(L, I), a(ll
``l) Determine the converted pixel from L+ a., I2. In addition, the logical operation formula for determining the converted pixel value in each region is divided into two regions, for example, as shown in Fig. 4 (b).
+g+-go as shown in . The position of the converted pixel is 2
For example, if it is in the area corresponding to g shown in FIG. 4(a), the converted pixel is.

b” g s(a kLn a k (Li2)+ a
(kφ violet) L+ a(kill (jull)=a
kL(a k(LSI) ” a (k+1) (ju
ll +a (k+1)L)” aII(LSI) a
(kill +tel) a(k+l) Determined from L.

An example of realizing one or more conversion processes according to the present invention.

Shown in Figure 1.

In FIG. 1, 1 is the coordinate value (X) of the converted pixel.

Y) and the conversion magnification α2β.

Read-only memory for input reference pixel position determination (RO
MI), 2 is the coordinate value of the converted pixel (X.

Y) and conversion magnification α, β.

A read-only memory (ROM) for input reference pixel position determination outputs the y-coordinate value of the upper left pixel among the four reference pixels.
2), 3 is a logical operation that outputs a logical operation mode corresponding to the positional relationship between the reference pixel and the converted pixel by inputting the coordinate values (X, Y) of the converted pixel and the conversion magnification α, β. Read-only memory for mode output (ROM3)
It is. 4 is a memory that stores screen data before conversion.

The pixel information corresponding to the coordinates specified by ROMI and ROM2 and the remaining three reference pixel information corresponding to the specified coordinates are output. 5-1 to 5-4 store reference pixel information; register 26 is a gate circuit; 7 receives the logic operation mode output from the ROM 3 and the contents of registers 5-1 to 5-4 and outputs a converted pixel value; This is a read-only memory (ROM7) for outputting converted pixels.

Note that the conversion processing function is ROMI to ROM3. ROM7
The reason why it can be stored in ROM as shown in FIG.
) and the conversion magnification.

This is because the coordinate values of the reference pixel and the positional relationship between the reference pixel and the converted pixel are uniquely determined.

The operation shown in FIG. 1 will be explained. First, the coordinate of b in Figure 2 (X
, Y) and conversion magnification α, β as ROMI, R shown in FIG.
OM2. Input to ROM3. The ROMI outputs the X coordinate xk of the reference pixel akL shown in FIG.
2 outputs the y coordinate yL of +akL. ROM3
4(b), which corresponds to the area of FIG. 4(a), is outputted from the logical operation mode g shown in FIG. 4(b).

Next, by inputting +xk+yL into memory 4, akL corresponding to (Xm, 3',) and memory 4
Since the coordinate value input to indicates the upper left pixel among the four reference pixels, pixel a shifted by one in the X direction
k (L. 3., and the pixel a (k
. 1. , pixel a (kill < LSll) shifted by one in the x and The gate circuit 6 is turned on and the reference pixel value and logical operation mode are input to the ROM 7.The ROM 7 outputs the value of the converted pixel shown in FIG.

The above operations are realized by a combination of ROM access operations without microprogram control. Therefore, processing can be realized faster than screen conversion processing using conventional microprogram control. Also,
By changing the contents of various ROMs, it is possible to flexibly deal with changes and additions to conversion modes and algorithms, and there is no need for major hardware modifications unlike conventional wired logic systems.

[Explanation of effects]

As explained above, according to the present invention, the speed of the two-screen conversion process is increased by using a memory such as a read-only memory (ROM) for the one-screen conversion process.

Enables flexibility in changing conversion algorithms9
There is a great advantage that the screen conversion device can be used effectively.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the configuration of an embodiment of the present invention, Fig. 2 is an explanatory diagram of screen conversion, Fig. 3 is an explanatory diagram of screen conversion according to the present invention, and Fig. 4 is for explaining an example of conversion logical operation. This is a diagram. 1.2... ROM for determining input reference pixel position, 3...
ROM for logic operation mode output, 4...Memory, 5-1
~5-4...Register, 6...Gate circuit, 7...
・ROM for converted pixel output, A...Screen before conversion, B.
・Screen after conversion. Patent applicant: Nippon Telegraph and Telephone Corporation, patent attorney
Mori 1) An example of a single glaze of Kanji Zen θPL, Fig. 7, Fig. 1

Claims (1)

[Claims] In a screen conversion device that performs screen conversion by providing original image data and a screen conversion ratio, by providing pixel positions and screen conversion ratios of the converted screen, multiple images of the converted screen can be converted. A first memory that outputs a pixel position; a second memory that outputs a logical operation mode by giving the pixel position of the screen after conversion and a screen conversion ratio; and a third memory that outputs pixel values of the screen after conversion by giving a calculation mode, and the pixel positions of the screen after conversion and the screen conversion ratio are stored in the first memory and the second reading out the plurality of pixel positions and the logical operation mode of the screen to be converted, and providing the plurality of pixel values corresponding to the plurality of pixel positions of the input screen and the logical operation mode to the third memory; A screen conversion processing method characterized in that the screen conversion process is performed by outputting the pixel values of the screen after the conversion.