JP3314488B2 - Color image information data processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing color image information data. The present invention relates to an image information data processing method applied when converting into color image information data.

[0002]

2. Description of the Related Art When storing color image information data in a memory, it is common practice to compress and store the data in order to save storage capacity.

For example, R data representing a shade of red,
The color image information data of the RGB color system representing a color by a combination of G data representing a green tint and the B data representing a blue tint, and a color representing a color by a combination of data representing luminance and data representing a color difference. The data is converted into image information data and compressed at intervals of one pixel so that the data representing the color difference is omitted.

The CCIR 601 format is an example of color image information data that expresses a color by combining data representing luminance and data representing color difference. In the CCIR 601 format, luminance data is Y data, color difference data is Cr data and This is Cb data.

In the following description, for the sake of simplicity, the description will be made with the data format of the pixel data in the memory represented by the CCIR601 format.

That is, in the memory, it is easy to understand that pixels having Y data, Cr data and Cb data and pixels having Y data but not having Cr data and Cb data alternately exist.

In this way, the storage capacity is reduced to 2/3. This data compression method is generally called 4: 2: 2 data compression.

However, the color image information data of the CCIR 601 format stored in the memory after the 4: 2: 2 data compression is read out from the memory again, and
When converting to color image information data of the RGB color system, pixels having Y data, Cr data, and Cb data have original numerical values of R data, G data, B data,
That is, it is restored to the original color, but has Y data,
For a pixel from which Cr data and Cb data have been omitted, the average value and Cb of the Y data of the pixel and the Cr data of each pixel located before and after the pixel adjacent to the pixel.
R data obtained by conversion using the average value of the data,
Since the G data and B data are R data, G data, and B data of the pixel for convenience, the original numerical value R
The data, G data, and B data, that is, the original colors are not restored.

That is, a pixel having Y data but omitting Cr data and Cb data is converted into an intermediate color of the color of each pixel located before and after the pixel adjacent to the pixel.

Table 1 shows the original color image information data, the color image information data in the memory, and the color image information data read out again from the memory, corresponding to five adjacent pixels in sequence without data compression. Shows the respective numerical values.

Further, Table 2 shows that the original color image information data, the color image information data in the memory, and the color image information in the memory corresponding to five adjacent pixels in the case of 4: 2: 2 data compression. Each numerical value of the color image information data read out again is shown.

[0012]

[Table 1]

[0013]

[Table 2]

On the other hand, on a color screen of a personal computer or the like, a background image and a sprite image are superimposed,
Image processing for combining and creating a composite image is performed. Here, the sprite image is a screen on which main symbols are formed, and the background thereof is usually formed with a uniform color.

When a background image and a sprite image are superimposed and synthesized, a so-called transparent process is performed. Transparency processing is processing on the screen to cut out only the design in the sprite image and paste it on the background image. However, in order to perform the transparency processing, the background of the sprite image must be completely black, that is, R
When expressed in the GB color system, the condition is that all of the numerical values of the R data, G data, and B data are 0.

However, at the boundary between the design of the sprite image and the background, even if the original color of the background is completely black, it is stored in the memory through 4: 2: 2 data compression, and then is returned from the memory again. In the case of reading, for the reason described above, the pixel is converted into an intermediate color between the colors of the pixels located before and after adjacent to the pixel, and a portion that is not restored to the original perfect black occurs.

Then, in a background portion that is not restored to a complete black color, there is a problem that even if the background portion is superimposed and synthesized, the transparent processing is not performed. Actually, in a portion where the transparent processing is not performed, black spots appear on the synthesized screen, which impairs the appearance of the screen.

[0018]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and superimposes and combines a background image and a sprite image on a color screen.
It is an object of the present invention to provide a method for performing transparent processing without any trouble even at a boundary between a background of a sprite image and a design when performing image processing for creating a composite image.

[0019]

According to the present invention, in order to solve the above-mentioned problems, a data format of pixel data in a memory is a format comprising luminance data and color difference data.
Pixels having luminance data and color difference data, and color image information data stored in a state in which pixels having luminance data but omitting color difference data are alternately present,
When reading from the memory and converting it into color image information data expressed in the RGB color system, for a pixel in which the numerical value of the luminance data of the pixel data in the memory is 0,
Regardless of the presence or absence of color difference data, R data, G data,
The pixel data is converted so that all of the B data are 0. For a pixel having no luminance data of the pixel data in the memory that is not 0 and has no color difference data, the luminance data of the pixel and the pixel adjacent to the pixel are not included. Using the average value of the color difference data of each pixel positioned before and after the matching, the R data, G data, and B data obtained by conversion are defined as the R data, G data, and B data of the pixel. This is a characteristic color image information data processing method.

[0020]

According to the image information data processing method of the present invention, when superimposing and combining a background image and a sprite image, the reason why the transparent processing is performed without hindrance at the boundary between the background of the sprite image and the design is considered. , (Table 3) will be described in detail below.

However, in the following description, for the sake of simplicity, the data format of the pixel data in the memory is assumed to be CCIR60.
The description will be made on behalf of one format.

[0022]

[Table 3]

Now, the background is completely black.
Pixel information in the image information data of the sprite image_nFrom
Pixel_{n + 4}Up to the pixel_nWhen
Pixel _{n + 1}Is the border between the background and the symbol
Pixel on the background_{n + 2}From pixel_{n + 4}Until
Is on the design at the border between the background and the design
There is. That is, the pixel_nAnd pixels_{n + 1}Is RG
In the B color system, all of R data, G data and B data
Is 0.

When this color image information data is compressed in 4: 2: 2 data and stored in the memory, pixel _{n + 1} and pixel
The Cr data and Cb data of the pixel data corresponding to _{n + 3} are omitted. The Y data of the pixel data corresponding to the pixel _n and the pixel _{n + 1} are both 0. This is because the complete black means that the luminance is 0, and the Y data representing the luminance is 0.

When the color image information data stored in the memory is read out from the memory again, the pixel _n and the pixel
_{For n + 1} , since the Y data is 0, when converting into the RGB color system, the R data, G
Both data and B data become 0.

For pixel _{n + 2} and pixel _{n + 4} , Cr data and Cb data are not omitted, and Y data,
Since all data and Cb data are included, when converting to the RGB color system, the original R data,
G data and B data are restored.

For pixel _{n + 3} , the Cr data and Cb
Since the data is omitted, when converting to the RGB color system, the Y data corresponding to the pixel _{n + 3} and the Cr data corresponding to each of the pixel _{n + 2} and the pixel _{n + 4} are obtained by the method of the present invention. R data, G data, and B data obtained by conversion using a normal conversion method using the average value of Cb data and the average value of Cb data are used as R data, G data, and B data of pixel _{n + 3.} .

As a result, the pixels _n and _{n + 1} on the background of the sprite image are restored to the original completely black even after being read from the memory. Therefore, the background image and the sprite image are superimposed and synthesized,
When creating the composite image, the transparent processing is performed without any trouble at the boundary between the background of the sprite image and the design.

The pixels on the sprite image
_{n + 3}About the pixel_{n + 2}And pixels _{n + 4}Middle of each color of
It will not be restored to the original color,
Black spots appear on the composited screen
Compared to what happens, when viewed by the human eye,
There is almost no discomfort.

[0030]

FIG. 1 is a circuit diagram showing an example of a circuit for realizing a color image information data processing method according to the present invention.

In FIG. 1, reference numeral 1 denotes color image information data expressed in the CCIR 601 format as RGB data.
The IC chip 1 has a function of converting color image information data expressed in a color system (hereinafter simply referred to as an IC chip). The IC chip 1 has 27 terminals from 4 to 30.

Reference numerals 4 to 8 denote five input terminals for inputting signals corresponding to the Y data. That is, the Y data is represented by a 5-bit binary number, and binary signals corresponding to each bit are input to the input terminals 4 to 8.

Reference numerals 9 to 13 denote five input terminals for inputting signals corresponding to Cr data or Cb data. That is, the Cr data and the Cb data are each represented by a 5-bit binary number, and a binary signal corresponding to each bit of the Cr data and a binary signal corresponding to each bit of the Cb data.
The value signal is input to the input terminals 9 to 13 alternately.

Reference numerals 16 to 20 denote five output terminals for outputting signals corresponding to the R data. That is, the R data is represented by a 5-bit binary number, and binary signals corresponding to each bit are output from the output terminals 16 to 20.

Reference numerals 21 to 25 denote five output terminals for outputting signals corresponding to the G data. That is, the G data is represented by a 5-bit binary number, and binary signals corresponding to each bit are output from the output terminals 21 to 25.

Reference numerals 26 to 30 denote five output terminals for outputting signals corresponding to the B data. That is, the B data is represented by a 5-bit binary number, and binary signals corresponding to each bit are output from the output terminals 26 to 30.

Reference numeral 15 denotes a terminal for inputting a signal for determining whether the output terminals 16 to 30 are in an output state or a floating state (floating state).
It is commonly referred to as an “able” terminal (hereinafter abbreviated as an OE terminal). That is, when a high-voltage signal (hereinafter, abbreviated as an H signal) is input to the OE terminal 15, the output terminal 16
30 are in an output state, and when a low-voltage signal (hereinafter abbreviated as L signal) is input to the OE terminal 15, the output terminals 16 to 30 are in a floating state.

Reference numeral 14 denotes a clock terminal for inputting a clock pulse. When a clock pulse is input to the clock terminal 14, a signal is taken into the IC chip 1 from the input terminals 4 to 13. However, when a clock pulse is not input to the clock terminal 14, the IC is input from the input terminals 4 to 13. No signal is taken into chip 1.

In this embodiment, the IC chip 1
When a clock pulse is inputted eight times from the clock terminal 14 after a signal is inputted from the input terminals 4 to 13,
Signals are output from the output terminals 16 to 30.

Reference numeral 2 denotes an OR logic gate to which five signals are input.

Reference numeral 3 denotes a shift register, which has a function of moving the information set in the register to the left by the same number as the number of pulses input to the shift pulse input while maintaining data. In this embodiment, the shift register has eight stages. When a shift pulse is input eight times after data is input, data is output.

The input terminals 4 to 13 of the IC chip 1 are supplied from outside the circuit of this embodiment through signal lines 31 to 40.
The signal is input to. Note that the signal lines 31 to 35 branch on the way and also input to the OR logic gate 2.

The output of the OR logic gate 2 is input to the shift register 3, and the output of the shift register 3 is input to the OE terminal 15 of the IC chip 1.

A signal is input to the clock terminal 14 of the IC chip 1 from the outside of the circuit of the present embodiment through the signal line 41, and the signal line 41 branches on the way to input the shift pulse of the shift register 3. Also enter

The output terminals 16 to 30 of the IC chip 1
Are output to the outside of the circuit of this embodiment through signal lines 42 to 56. Note that the signal lines 42 to
Reference numeral 56 denotes a branch on the way, and each of the pull-down resistors 57 to
It is grounded via 71.

Now, from the outside of the circuit of this embodiment, Y data in the CCIR 601 format is input to the signal lines 31 to 35 as a 5-bit binary number.
0, CCIR601 format Cr data and Cb
Data is input alternately as a 5-bit binary number,
It is assumed that a clock pulse is input to the signal line 41.

When the Y data is 0, the signal line 31
Each of the 5-bit signals input to .about.35 is an L signal. Therefore, the output of the OR logic gate 2 becomes an L signal, and the L signal is input to the shift register 3, and at the same time, the L signal is input to each of the input terminals 4 to 8 of the IC chip 1.

After that, when the clock pulse is inputted eight times, the L signal is outputted from the shift register 3 and the L signal is inputted to the OE terminal 15 of the IC chip 1 at the same time as the I signal.
R of the result converted into the RGB color system inside the C chip 1
Signals corresponding to data, G data, and B data are about to be output from output terminals 16 to 30 of IC chip 1.

However, since the L signal is input to the OE terminal 15, the output terminals 16 to 30 of the IC chip 1 are in a floating state, and the converted R data, G data
The signals corresponding to the data and the B data are not output, and the signals output to the outside of the circuit of this embodiment through the signal lines 42 to 56 are all L signals by the pull-down resistors 57 to 71, respectively.

Therefore, the numerical values of the R data, G data, and B data output to the outside of the circuit of this embodiment are
Both become 0.

When the Y data is not 0, the signal line 31
At least one bit signal among the 5-bit signals input to .about.35 is an H signal. Therefore, the output of the OR logic gate 2 becomes the H signal, and the shift register 3 outputs the H signal.
A signal is input, and at the same time, a signal is input to each of the input terminals 4 to 8 of the IC chip 1.

After that, when the clock pulse is inputted eight times, the H signal is outputted from the shift register 3 and the H signal is inputted to the OE terminal 15 of the IC chip 1 at the same time as the I signal.
R of the result converted into the RGB color system inside the C chip 1
Signals corresponding to data, G data, and B data are about to be output from output terminals 16 to 30 of IC chip 1.

However, since the H signal is input to the OE terminal 15, the output terminals 16 to 30 of the IC chip 1 are in the output state, and the converted R data, G data, and B data are output.
The signal corresponding to the data is output from the output terminals 16 to 30 as it is. Then, the signals corresponding to the converted R data, G data, and B data are output to the outside of the circuit of the present embodiment through the signal lines 42 to 56 as they are.

Actually, if the Cr data and Cb data input to the signal lines 36 to 40 are not omitted, the original RGB data before being converted into the CCIR601 format is stored inside the IC chip 1. The data is converted into color data R data, G data, and B data.
When the Cr data and Cb data input to the IC chip 1 are omitted, the data input immediately before the input of the data, that is, the data of the immediately preceding pixel in the IC chip 1 Is converted into data that is input immediately after this data is input, that is, data of an intermediate color between the data of the next adjacent pixel.

[0055]

According to the color image information data processing method of the present invention, the color image information data stored in the memory after the data compression is read out from the memory again, and then the background image and the sprite image are displayed on the color screen. When performing image processing to create a composite image by superimposing and synthesizing, the transparent processing is performed without hindrance even at the boundary between the background of the sprite image and the design, so that the synthesized screen is sufficiently This has the effect that the aesthetic appearance can be maintained.

Further, the color image information data processing method of the present invention uses a circuit combining simple logic gates.
Since it can be realized simply, there is also an effect that the circuit design process does not require much labor and cost, and the cost required for manufacturing and assembling the circuit can be reduced.

[0057]

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating a circuit according to an embodiment for realizing a color image information data processing method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 IC chip 2 OR logic gate 3 Shift register 4-13 Input terminal 14 Clock terminal 15 OE terminal 16-30 Output terminal 31-56 Signal line 57-71 Pulldown resistance

Continuation of the front page (56) References JP-A-62-16696 (JP, A) JP-A-2-29093 (JP, A) JP-A-4-6982 (JP, A) JP-A-4-90287 (JP) JP-A-4-358490 (JP, A) JP-A-5-37956 (JP, A) JP-A-5-199546 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) H04N 9/74 G06T 1/00 H04N 11/02

Claims (1)

(57) [Claims] In a memory, a data format of pixel data is a format including luminance data and chrominance data, and a pixel having luminance data and chrominance data and a pixel having luminance data but omitting chrominance data are included. When the color image information data stored alternately is read from the memory and converted into the color image information data expressed in the RGB color system, the numerical value of the luminance data of the pixel data in the memory is changed. Regarding the pixel which is 0, R data, G data, B data
The data is converted so that all of the data is 0. For a pixel having no luminance data of pixel data in the memory that is not 0 and has no color difference data, the pixel is adjacent to the luminance data of the pixel. R data, G data, and B data obtained by conversion using the average value of the color difference data of each pixel positioned before and after are used as R data, G data, and B data of the pixel. Color image information data processing method.