JPH03174188A - Method for enlarging data for pixel data display device - Google Patents

Abstract

PURPOSE:To reduce a circuit by combining a selector circuit and a multiplexer circuit and generating desired zoom data. CONSTITUTION:A means 7 for generating address offset 7' which shows the position of an optional pixel in the data area of pixel data, and the selector circuit 9 where selectors 1-4 as many as the number of bits of the address offset 7' are connected in serial are provided so as to generate the pixel data which should be enlarged by controlling the data selectors 1-4 inside with the address offset 7'. As to the generated pixel data, only the pixel data having enlarging magnification specified with a zoom factor is selected in a multiplexer circuit 5 and generated as the zoom data which is enlarged at the desired magnification. Thus, the scale of the circuit is made small.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a display device for pixel data.

[Prior Art] As shown in FIG. 2, in the conventional method for enlarging pixel data, zoom data is obtained by providing a selector circuit for each enlargement magnification. In other words, zoom data with an enlargement factor of 2 can be obtained from the selector circuit 10, and zoom data with an enlargement factor of 4 can be obtained from the selector circuit ffg.
Obtained from ll. Similarly, magnification rate = 8, magnification rate =
The 16 zoom data can be obtained from the selector circuit 12 and the selector circuit 13, respectively.

[Problems to be Solved by the Invention] However, in the above method, a selector circuit must be provided each time the magnification that can be enlarged is increased, resulting in a problem that the scale of the circuit increases.

An object of the present invention is to obtain zoom data expanded in the scan line direction even if the magnification increases, without providing a selector circuit for each magnification.

[Means for Solving the Problem] In order to achieve the above object, in the pixel data expansion method of the present invention, as shown in FIG. Desired zoom data is obtained by combining a selector circuit 9 controlled by a selector circuit 9 and a multiplexer circuit 5 controlled by a zoom factor that determines the magnification of pixel data.

[Operation] In the present invention, in the selector circuit of FIG. 1, the internal data selector 1.2.3.4 is
The pixel data to be enlarged is generated by controlling pixel data are selected and generated as zoom data magnified to the desired magnification.

[Embodiment 1] An embodiment of the present invention will be described in detail with reference to FIGS. 1, 3, and 4. Pixel data 18 having a 16-bit data area shown in FIG. 3 is applied to selector 1 in FIG. At the same time, this pixel data becomes an input to the multiplexer 5 at the subsequent stage. The 16-bit pixel data 1a is used as zoom data with an enlargement factor of 1 (1x enlargement).

Next, the pixel data given to the selector 1 is divided into an upper byte and a lower byte by the signal (A3) of the third bit of the address offset 7', which indicates the position of an arbitrary pixel within the word of 16-bit data. It will be done. In other words, on the circuit, when A3=1, selector l
Of the 16-bit data given to the A-side input, the upper 8 bits are selected and become the output of the selector 1.

Conversely, when A3=O, the lower 8 bits which are the B side input are selected and become the output of selector 1. The upper or lower 8-bit data selected here is given to the selector 2 at the next stage. Further, each bit of the 8-bit data is doubled in the buffer circuit 6 to become 16-bit data 1b. This 16
The bit pixel data 1b is sent to the subsequent multiplexer as zoom data 19 with an enlargement factor of 2 (2x enlargement).
This will be the input of 5.

Next, the above 8-bit data given to selector 2 is the 2nd bit signal (A2) of address offset 7'.
It is divided into upper and lower 4 bits by . The 4-bit data selected here is given to the selector 3 at the next stage. At the same time, each bit of the 4-bit data is expanded four times in the buffer circuit 6 to become 16-bit data 1C. This 16-bit pixel data IC has an enlargement factor of 4 (4 times enlargement).
The zoom data 20 is input to the multiplexer 5 at the subsequent stage.

Similarly, the 4-bit data given to the selector 3 is the l-th bit signal (A1
) is divided into upper and lower 2 bits.

The 2-bit data selected here will be used by the next stage selector.
given to 4. At the same time, each bit of the 2-bit data is expanded eight times in the buffer circuit 6 to become 16-bit data ld. This 16
The bit pixel data 1d is sent to the subsequent multiplexer as zoom data 21 with an enlargement factor of 8 (8x enlargement).
This will be the input of 5.

Furthermore, zoom data 22 with an enlargement factor of 16 (16 times enlargement) converts the 2-bit data given to the selector 4 into the O-th bit signal (AO
) and then enlarged by 16 times in the buffer circuit 6 at the next stage. 1e is expanded 16-bit pixel data.

The zoom data for each magnification factor obtained in this way is
In the final stage multiplexer 5, the zoom factor 8' (ZOlZl, Z2) which determines the enlargement magnification is selected again, and only the 16-bit data of a certain enlargement magnification becomes the output of the multiplexer 5.

That is, the 16-bit data selected here is zoom data obtained by enlarging pixel data in the scan line direction to a desired value.

In the above embodiment, the enlargement magnification=1. Enlargement magnification = 2, Enlargement magnification = 4, Enlargement magnification = 8. 16-bit zoom data is obtained by any one of the enlargement factors of 16. Note that the zoom data shown in FIG. 3 is a specific example when the address offset is 0, and the zoom data shown in FIG.
This is an example of the case.

Finally, referring to FIG. 5, in FIG.
Under the control of the pixel data controller 21, the data are sequentially read out onto the data bus 22 according to memory addresses generated by the microprocessor 27. At this time, the pixel data controller 21 uses an internal zoom control circuit, that is, the zoom data enlargement method shown in FIG. 1, to enlarge the pixel data 200 according to the enlargement magnification indicated by the zoom factor. The zoom data enlarged here is transferred to an image memory 24 controlled by an image data controller 23 via a data bus 22.

Further, the zoom data transferred to the image memory 24 is transferred as image data to the video/F 25 at the subsequent stage, converted into a video signal, and then sent to the CRT 26. Through the above procedure, the pixel data stored in the pixel memory can be enlarged to the magnification specified by the zoom factor and displayed on the CRT.

[Effects of the Invention] According to the present invention, as illustrated in FIG. 1, there is no need to provide a selector circuit for each magnification factor. Therefore, according to the present invention, compared to the conventional method of enlarging pixel data in the scan line direction, it is possible to significantly reduce the circuit scale for realizing enlargement of pixel data. Furthermore, by reducing the size of the circuit, the number of parts used can be reduced, so it is possible to reduce costs and improve the reliability of the circuit.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of data expansion according to the present invention, and FIG.
The figure is a block diagram of conventional data enlargement, Figures 3 and 4 are explanatory diagrams showing specific examples of zoom data, and Figure 5 is
FIG. 2 is a block diagram of a zoom data display device.・Data selector ・Data selector ・Data selector ・Data selector ・Multiplexer ・Buffer circuit ・Address offset generation means ・Zoom factor generation means ・More than selector circuit

Claims (1)

[Claims] A display device for controlling pixel data, comprising: an address offset generating means indicating the position of an arbitrary pixel in a data area of pixel data; a selector circuit in which selectors corresponding to the number of bits of the address offset are connected in series; and a pixel. By combining a zoom factor generating means that determines the data enlargement magnification and a multiplexer circuit controlled by the zoom factor, zoom data enlarged to the enlargement magnification specified by the zoom factor is generated. Data expansion method in the scanline direction.