JP3080087B2 - Image processing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image processing method and apparatus for superimposing a plurality of images.

[0002]

2. Description of the Related Art In image processing, there is a process of superimposing and displaying a plurality of images in various modes. For example, there is a case where a moving image occupying a partial area is combined with a certain background image, or characters and symbols are superimposed and displayed on a normal moving image. In such a case, a superimposed image such as a moving image to be synthesized or a character to be superimposed includes a region where some image to be displayed exists and a region where the background of the superimposed image is to be displayed as it is because no image exists. Therefore, for the former region, images are superimposed according to a predetermined mixture ratio,
For the latter area, a process is performed in which the superimposed image is made transparent and the superimposed image is displayed. In addition, there is a case where a predetermined translucent image such as through a frosted glass is superimposed on the image. In this case, the superimposed image is made transparent and a portion of the image to be superimposed corresponding to an area of the translucent image. Is attenuated at a predetermined ratio.

FIG. 4 shows the configuration of a conventional image processing apparatus for performing such image superimposition processing. In this figure, YA, C
bA and CrA are image data of a superimposed image (hereinafter, referred to as a “high-priority image”) that is superimposed and displayed with priority, and YB, CbB, and CrB are superimposed on the high-priority image. This is image data of a superimposed image to be a lower image (hereinafter, referred to as a “low-priority image”). These two
As for the image data of the system, YA and YB correspond to luminance data, CbA and CbB correspond to saturation data, CrA and CrB correspond to hue data, and are sequentially supplied for each pixel of a high priority image and a low priority image. (In the following, the saturation and the hue are sometimes simply referred to as “color”.)

The flag is a flag for designating, for each pixel, whether the high-priority image is transparent or non-transparent. The flag is "1" if it is transparent, and "0" if it is not transparent. The α blending ratio indicates the mixing ratio of the pixel values of each image when the high-priority image and the low-priority image are overlapped. BL10, BL20, BL30 are flags
Luminance data YA based on flag and α blend ratio
And YB, saturation data CbA and CbB, hue data CrA
And a blender for performing an α blending process of CrB and CrB, and outputs the processing result as one system of image data Y (blended luminance), Cb (blended saturation), and Cr (blended hue data).

In such a configuration, image data of two systems of YA, CbA and CrA and YB, CbB and CrB, a flag and an α blending ratio are sequentially supplied for each pixel, and these are superimposed as input data. Is performed. Assuming that the input flag flag is "1", the blenders BL10, BL20, and BL30 each make the high-priority image transparent (the YA, CbA, and CrA are not used). As the superimposition processing, as described above, the processing of outputting the low-priority image as it is (hereinafter, referred to as “transparency processing”) and the processing of attenuating the low-priority image at a predetermined ratio to make it translucent (hereinafter, “translucent processing”) Processing ”). Therefore, each image data (YA, CbA, CbB) of the high priority image is represented by A,
Each image data (YB, CbB, Cr
Assuming that B) is B, each blender performs the following operations: for transparent processing: A × 0 + B × 1; for semi-transparent processing: A × 0 + B × β, and outputs the calculation results as output data (Y, Cb, C).
r).

On the other hand, if the input flag flag is "0", a process of superimposing the high-priority image and the low-priority image according to the α blend ratio (hereinafter referred to as "superimposition process") is performed. . That is, each blender: In the case of the superposition processing: A × α + B × (1−α) is calculated, and the calculation result is used as output data.

[0007] This superposition processing corresponds to a normal α blending processing, and the blenders BL10, BL2
0, BL30 switches between this processing and transparent processing or translucent processing depending on the value of the flag flag. That is, in the process in which the flag flag is “1”, if “α = 0”, the above transparent process is performed by substituting the same into the same arithmetic expression as in the superposition process,
If “α ≠ 0”, the coefficient of A in the arithmetic expression is set to “0”.
The semi-transparent process is performed by setting the coefficient of B as “(1−α)” as it is. Therefore, in the case of the translucent process, the transmission rate β of the low-priority image is specified by “1−α” (α itself specifies the above-described predetermined attenuation rate).

As another conventional image superimposition processing technique, for example, there is one proposed in Japanese Patent Application Laid-Open No. Hei 6-335022. In this publication, when each bit of RGBI (red, green, blue, luminance) data of one image is “0”, it is determined that the image is transparent, and the transparent image is switched to the other image to switch the two images. A technique for performing superposition is disclosed.

[0009]

By the way, in the above-mentioned conventional image processing apparatus, the distinction between transparent / non-transparent and the α blend ratio of the high priority image is designated for each pixel. Must be input separately from the pixel data. For this reason, there is a problem that the amount of required input data is large and the input data bandwidth is very wide.

In the case of performing translucent processing, the transmittance of a low-priority image is designated by one α-blending ratio for each pixel in the conventional image processing apparatus. Different transmittances cannot be applied to colors (CbB and CrB). In order to make this possible, it is only necessary to input two α blend ratios that specify the transmittance for each of the luminance and the color when performing the translucent processing. And the input data bandwidth is further widened.

The present invention has been made in view of such circumstances, and does not require data for designating transparency or non-transparency different from image data as input data, so that ordinary α
In addition to blend processing, it is possible to perform transparent processing and translucent processing, reduce the amount of input data required for superimposition processing of multiple images and narrow the input data bandwidth,
It is an object of the present invention to provide an image processing technique capable of performing translucent processing for controlling transmittance independently for parameters specifying each pixel such as luminance and color.

[0012]

According to the first aspect of the present invention,
In an image processing method in which each pixel superimposes two images represented by a plurality of parameters, information specifying that each pixel is transparent or translucent is included in one of parameters representing each pixel of one image. Along with the parameter, another parameter representing a pixel that specifies that the pixel is to be made translucent by the parameter is information that specifies the transmittance of a pixel in the other image on which the pixel is to be superimposed, and for each of the pixels, When the parameter specifies transparency, the pixel in the other image is set as a pixel after superimposition, and when the parameter specifies translucency, the pixel in the other image is reduced by half with the transmittance specified by the other parameter. The transparent pixel is regarded as a pixel after superimposition, and when neither the transparent nor the translucent is specified for the parameter, the pixel and the other image are not included. It is characterized in that the pixels after superimposing the pixel superposing the pixel.

According to a second aspect of the present invention, in the image processing method according to the first aspect, when the other parameters are two or more, the transmittance specified by each of the parameters is set to the pixel in the other image. It is characterized in that, when the transmittance of the different parameter is represented and the pixels in the other image are made translucent, the different parameters are made translucent at the respective transmittances specified by the other parameters.

According to a third aspect of the present invention, in the image processing apparatus for superimposing two images in which each pixel is represented by a plurality of parameters, each pixel is set to one of parameters representing each pixel by setting the pixel to be transparent or translucent. Information that specifies that the pixel is to be made semi-transparent by the parameter, and information that specifies the transmittance of the pixel in the other image on which the pixel is to be superimposed. Data input means for inputting the obtained image data and the other image data, and for each of the pixels, when the parameter specifies transparency, outputs a pixel in the other image, and the parameter is translucent. When specifying, the pixels in the other image are translucently output at the transmittance specified by the other parameter, and the parameters are transparent and semi-transparent. If neither is specified Ming is characterized by having processing means for outputting by superimposing the pixel in the other image and the pixel.

According to a fourth aspect of the present invention, in the image processing apparatus according to the third aspect, when the other parameters are two or more, the data input means sets the transmittance specified by each of the parameters. The transmittance of a different parameter representing a pixel in the other image, and the processing means, when the pixel in the other image is translucent, each of the different parameters at the respective transmittance specified by the other parameter It is characterized by being translucent.

According to a fifth aspect of the present invention, in the image processing apparatus of the third or fourth aspect, the processing means determines whether the respective pixels are to be superimposed in a transparent, translucent, or superimposed manner by the parameter. A determination unit that determines based on the above, the selection unit that selects the other parameter when the superimposition mode determined by the determination unit is translucent, and a predetermined image mixing ratio otherwise, When the superimposition mode is transparent, the pixels in the other image are output,
When the superimposition mode is translucent, a pixel in the other image is translucently output at a transmittance designated by a parameter selected by the selection unit, and is output when the superimposition mode is superimposition. Calculating means for superimposing pixels in the other image at an image mixing ratio selected by the selecting means and outputting the overlapped image.

According to a sixth aspect of the present invention, in the image processing apparatus of the fifth aspect, the image mixing ratio is a predetermined constant.

According to a seventh aspect of the present invention, the image processing apparatus according to any one of the third to sixth aspects is provided in a plurality of stages, and in the second and subsequent image processing devices, each of the data input means inputs. The other image data is used as the output of the preceding image processing apparatus, and the data of the image to be further superimposed on the output image is used as the image data.

[0019]

According to an eighth aspect of the present invention, in the image processing method for superimposing two images in which each pixel is represented by a plurality of parameters, each pixel is replaced by one of the parameters representing each pixel of one image. Along with the information that specifies that the pixel is to be transparent, another parameter representing a pixel that specifies that the pixel is to be made semi-transparent by the parameter is information that specifies the transmittance of the pixel in the other image. When the parameter specifies translucency, a pixel in the other image that is translucent at the transmittance specified by the other parameter is set as a pixel after superimposition.

[0021]

According to a ninth aspect of the present invention, in the image processing apparatus for superimposing two images in which each pixel is represented by a plurality of parameters, each pixel is made translucent as one of the parameters representing each pixel. And the other data representing a pixel that specifies translucency by the parameter is information that specifies the transmittance of a pixel in the other image, and image data of the other image. Data input means for inputting image data, and for each pixel, when the parameter specifies translucency, output the pixel in the other image in a translucent state at a transmittance specified by the other parameter. And processing means for performing the processing.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS <Structure> An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating a configuration of an image processing apparatus according to an embodiment of the present invention.

In this figure, YA, CbA and CrA
Is image data of a high-priority image superimposed and displayed on top, and YB, CbB, and CrB are image data of a low-priority image which is a lower image on which the high-priority image is superimposed. It is. Of these two types of image data, YB is normal luminance data, CbB is normal chroma data, CrB is normal hue data, and data (pixel data) for each pixel of the low priority image is sequentially supplied. It is supposed to be.

On the other hand, YA of the high-priority image depends on the value of the image.
It is data representing one of the other semi-transparent. or,
CbA is data representing normal saturation or translucency of luminance data YB (attenuation rate of YB × luminance gradation number).
rA is data representing the translucency of normal hue or saturation data CbB and hue data CrB (attenuation rate of CbB and CrB × color gradation number). That is, for each pixel data, when the data YA is a value specifying normal luminance, the data CbA and the data CrA are also normal color data, and the data YA makes the high priority image transparent. (Hereinafter referred to as “transparency specification value”), the data CbA and the data CrA are values indicating colorlessness (particularly, there is no data specifying a color), and the data YA is translucent. (Hereinafter referred to as “translucent designated value”), the data CbA is a value representing the translucency of the luminance data YB, and the data CrA is a value representing the translucency of the color data CbB and CrB. .

For example, if the luminance and the color are each set to 256 gradations, the data YA, CbA, C
By assigning the value of rA as follows, the above-described correspondence of each data can be realized. Normal Translucent Translucent YA2 to 25501 CbA (Normal chroma gradation value)-YB attenuation rate x 256 CrA (Normal hue gradation value)-CbB and CrB attenuation rate x 256

Here, the data CbA, C
rA designates the translucency of the luminance data YB, the color data CbB and the CrB.
And CrA are data having values of 0 to 255, which also represent normal saturation and hue, and substantially correspond to those representing the attenuation rate of low-priority images in translucent processing,
The transmittance is designated by “1-decay rate”. Note that the above data allocation is merely an example, and the data YA
Of the specified transparency and semi-transparency values to values other than 0 and 1 (in short, it is sufficient to secure two values from any of 0 to 255), and to set the translucency represented by the data CbA and CrA. Conversely, it may be assigned. The same applies to the case where the number of gradations is other than 256.

As described above, in the present image processing apparatus, since two values of the data YA which originally represent the luminance of a certain number of gradations are assigned to the designated transparent value and the designated semi-transparent value, The luminance becomes coarse by two gradations. However, even if the number of gradations of luminance is reduced by two gradations in normal display, it has almost no effect on the viewer. Even in the above allocation example, the lowest gradation of 256 gradations is 2
Since the luminance of the gradation is merely a dark luminance that is indistinguishable, these gradations are compressed to “YA”
There is no problem even if it is expressed by a common value of "= 2".

The data CbA for performing the translucency processing
And CrA do not specify any information relating to the display image, so that there is no problem even if they are assigned the translucency of the brightness and the color as described above.

On the other hand, the constant α blend ratio in FIG. 1 is a constant value indicating a mixture ratio (weight) of each image pixel value when a high priority image and a low priority image are superimposed. Specifically, according to the image to be superimposed, the ratio of the high-priority images in the superimposition processing is specified in advance in the range of 0 to 1 as the constant α blending ratio.
The constant α blend ratio and the two sets of image data are generated by predetermined data generating means (not shown) and supplied as input data.

DE receives the data YA, and receives the transparent enable signal TPE and the translucent enable signal TL according to the value.
The output terminal of the translucent enable signal TLE is connected to the selectors SE1, SE2 and the blenders BL1, BL2, and BL3, and the output terminal of the transparent enable signal TPE is connected to the blenders BL1, BL2, and BL3. ing. When the data YA has the transparency designation value, the decoder DE transmits the translucent enable signal TL.
E is disabled (disabled state), the transparent enable TPE signal is activated (active state), and if the data YA is a translucent designated value, the translucent enable signal T
LE is activated, and the transparent enable TPE signal is disabled. If the data YA is neither the transparent specified value nor the translucent specified value, the translucent enable signal TL is output.
E and the transparent enable TPE signal are both disabled.

The selector SE1 receives the data CbA and the constant α blend ratio, selects one of them according to the translucent enable signal TLE from the decoder DE, and outputs it to the blender BL1. Here, the selector SE1 selects the data CbA when the translucent enable signal TLE is active, and selects and outputs the constant α blending ratio when the translucent enable signal TLE is disabled. However,
When the data CbA is selected, since the data CbA represents the translucency of the luminance data YB (described later), the data CbA is converted into a luminance decay rate αY divided by the number of luminance gradations and output.

The selector SE2 receives the data CrA and the constant α blend ratio, selects one of them according to the translucent enable signal TLE from the decoder DE, and outputs it to the blenders BL2 and BL3. Here, the selector SE2 selects the data CrA when the translucent enable signal TLE is active, and selects and outputs the constant α blending ratio when the translucent enable signal TLE is disabled. However, when the data CrA is selected, since the data CrA represents the translucency of the color data CbB and CrB (described later), the data CrA is converted into a color decay rate αC divided by the number of color gradations. Output.

The blenders BL1, BL2, and BL3 respectively store data YA and luminance data YB, data CbA and saturation data CbB, data CrA and hue data CrB.
These are mixed according to the signals from the decoder DE and the selectors SE1 and SE2, and the blended output luminance data Y, output saturation data Cb, and output hue data C
Output as r. These blenders BL1, BL2, and BL3 have different inputs and outputs, but have the same internal configuration. Its internal configuration is shown in FIG. 2 and will be described in detail below.

In FIG. 2, an input A is image data of a high-priority image, which corresponds to data YA in the blender BL1, data CbA in the blender BL2, and data CrA in the blender BL3. The input B is image data of a low priority image, which corresponds to the luminance data YB in the blender BL1, the saturation data CbB in the blender BL2, and the hue data CrB in the blender BL3. α 'is an output from the selector, and the blender BL1
, The constant α blending rate or luminance decay rate αY output from the selector SE1, the blenders BL2 and BL
In 3, the constant α blending rate or the color decay rate αC output from the selector SE2 corresponds to this.

Bl1 receives input A at one input terminal,
A selector whose input to the other input terminal is held at “0”, receives a translucent enable signal TLE from the decoder DE as a selection signal, and when this is active, selects the input of “0” and outputs it. In the case of disable, the input A is selected and output. A selector bl2 receives a selector output α 'at one input terminal and receives a transparent enable signal TPE as a selection signal while the input to the other input terminal is held at “0”. The input of "0" is selected and output. In the case of disable, the selector output α 'is selected and output.

An arithmetic unit bl3 receives the outputs of the selectors bl1 and bl2 and the input B, and performs predetermined arithmetic processing. Specifically, inputs from the selector bl1 are A ', b
Assuming that the input from l2 is α ″, the arithmetic unit bl3 performs an operation of A ′ × α ″ + B × (1−α ″), and outputs the result to the selector bl4.

The selector bl4 is a selector that receives the input B at one input terminal and the output of the arithmetic unit bl3 at the other input terminal, selects one of them, and sets it as a blender output. Transparent enable signal TP
E, and if it is active, select input B,
In the case of disable, the output of the arithmetic unit bl3 is selected and output. It should be noted that the blender output due to this is the blender BL
1 corresponds to the output luminance data Y, the blender BL2 corresponds to the output saturation data Cb, and the blender BL3 corresponds to the output hue data Cr.

The blenders BL1, BL2 and BL3 of FIG.
Is configured as described above.
These blenders, the decoder DE, and the selector SE1
The input data described above is generated and supplied by a predetermined data generation unit to an image processing circuit composed of the image processing circuits SE2 and SE2.

<Operation> Next, the operation of the above configuration will be described. In the present image processing apparatus, two types of image data of the above-described high-priority image data YA, CbA and CrA, and low-priority image luminance data YB, saturation data CbB and hue data CrB are provided for each pixel. The pixel data is sequentially supplied, and superimposition processing is sequentially performed for each pixel using the pixel data as input data. The procedure of the superimposition processing cycle for each pixel is shown in FIG. 3 and will be described below with reference to FIG. In the following description, the description will proceed on the assumption of the above-described data allocation example in the case where the luminance and the like are set to 256 gradations.

When new image data of the high-priority image and the low-priority image is supplied and the pixel data is updated (step S0), the data YA of the updated pixel data is set to the transparent designated value "0". "Is the decoder D
It is determined by E (step S1). Assuming that this pixel data is for a pixel in an area in which a low-priority image is to be displayed with the high-priority image being transparent, and that the data YA is “0”, the determination result here is “Y
ES ", and the process proceeds to step S2.

In step S2, the decoder DE activates the transparent enable signal TPE and disables the translucent enable signal TLE. In addition, the selectors SE1 and SE2 select the constant α blending ratio, and the blenders BL1 and BL2 respectively.
2 and BL3.

Then, each blender receives signals from the decoder DE and the selectors SE1 and SE2, and converts them into updated data YA and luminance data YB, data CbA, saturation data CbB and data CrA, and hue data CrB. (Step S)
3).

At this time, in each blender, the input A is output from the selector bl1, the signal of “0” is output from the selector bl2, and the operation is performed by the operation unit bl3. Regardless of the result, , Selector b receiving active transparent enable signal TPE
The input B is output by 14 (however, in this case, the operation result in the operation unit bl3 is also “A × 0 + B × (1-0) =
B ″ becomes B.) As a result, the output luminance data Y,
The luminance data YB, the chroma data CbB, and the hue data CrB of the low-priority image are output as they are as the output chroma data Cb and the output hue data Cr. can get.

On the other hand, if the data YA is not "0", the result of the determination in step S1 is "NO" and the flow advances to step S4, where the decoder DE sets the data YA to the semi-transparent designated value "1". Is determined. Here, if the updated pixel data is for a pixel in the translucent high-priority image area and the data YA is “1”, the determination result is “YES” and the processing in step S5 is performed. Proceed to.

In step S5, the decoder DE disables the transparent enable signal TPE and activates the translucent enable signal TLE. This also causes the selectors SE1 and SE2 to output data Cb
Select A and CrA. In this case, the data YA is "1".
Therefore, the data CbA and CrA represent the translucency of the luminance data YB and the color data CbB and CrB, respectively. Therefore, the selector SE1 divides the selected data CbA by the number of luminance gradations “256” and outputs the result to the blender BL1 as a luminance attenuation rate αY.
Divides the selected data CrA by the number of color gradations “256” and outputs the result to the blenders BL2 and BL3 as a color decay rate αC.

Then, the process proceeds to step S3, in which each blender outputs signals from the decoder DE and the selectors SE1 to SE2 and updated pixel data (YA, YB, Cb).
A and CbB or CrA and CrB).

At this time, in each blender, a signal of "0" is output from the selector bl1 and the selector bl2
Outputs a selector output α ′. Therefore, the arithmetic unit b
In 13, A ′ × α ″ + B × (1−α ″) = 0 × α ′ + B × (1−
α ′) = B × (1−α ′) is performed, and the calculation result is selected and output by the selector bl4.

That is, “brightness data YB × (1−attenuation rate αY)” is output from the blender BL1 as output brightness data Y, and “saturation data CbB × (1−color decay rate αC)” is output from the blender BL2. "Is output saturation data Cb
Is output from the blender BL3 as “hue data C”.
rB × (1−color decay rate αC) ”is output as output hue data Cr, and pixel data after translucent processing on which a translucent high-priority image is superimposed is obtained.
“Luminance decay rate αY)” corresponds to the transmittance of luminance, and “(1-
The color decay rate αC) "is equivalent to the transmittance of the color,
In the present image processing apparatus, these are converted into data CbA and CbA, respectively.
It is controlled by the value of rA. This realizes a translucent process in which the transmittance can be independently controlled for luminance and color.

In this image processing apparatus, the transmittance is controlled by the data CbB and CrA as described above.
A different transmittance can be applied to each pixel even though the α blend rate is a constant. This means that it is possible to perform transparent processing or translucent processing that applies different transmittance to each pixel without having to give data specifying transparency / non-transparency or α blending ratio for each pixel. means. That is, according to the image processing apparatus, the transparent processing and the translucent processing for each pixel can be performed with a small input data amount.

On the other hand, if the data YA is not "0" and
If it is not “1”, that is, the updated pixel data is for a pixel in the area where the high-priority image and the low-priority image are superimposed and displayed, and the data YA is “2”.
To “255”, the decoder D
E, the determination results in steps S1 and S4 are both "N".
O ", and the process proceeds to step S6.

In step S6, the decoder DE disables both the transparent enable signal TPE and the translucent enable signal TLE, and thereby the selectors SE1 and SE1 are disabled.
SE2 selects the constant α blending ratio and outputs it to Blender BL1, Blender BL2 and BL3, respectively. Then, the process proceeds to step S3, where each blender performs an arithmetic process based on the signals from the decoder DE and the selectors SE1 and SE2 and the updated pixel data.

At this time, in each blender, the input A is output from the selector bl1, and the selector output α 'is output from the selector bl2. Therefore, in the arithmetic unit bl3, A ′ × α ″ + B × (1−α ″) = A × α ′ + B × (1-
α ′) = A × α + B × (1−α) is performed, and the calculation result is selected and output by the selector bl4.

This corresponds to a process of superimposing a high-priority image and a low-priority image in accordance with a constant α-blending rate, that is, a normal α-blending process. In this way, when the data YA is not a specific value such as the designated transparent value or the designated translucent value, a normal superimposition process is performed, whereby the pixels of the high priority image and the pixels of the low priority image are distinguished from each other. Output luminance data Y, output saturation data Cb, and output hue data Cr representing the mixed pixel after the superimposition process are obtained.

As described above, when the pixel data is updated, according to the value of the data YA, the transparent processing in steps S1, S2 and S3, the translucent processing in steps S1, S4, S5 and S3, the step S1, Any one of the superposition processes in S4, S6, and S3 is executed. Then, this processing operation is repeated every time the pixel data is updated, and the pixels of the high priority image and the pixels of the low priority image are sequentially superimposed. As a result, the superimposition process of the high-priority image and the low-priority image including the transparent process and the translucent process in addition to the normal α blending process is performed, and one system image representing the superimposed image of these two images Data (Y, C
b, Cr) are obtained. The image data on which the superimposition processing has been performed is supplied to predetermined display means to be subjected to subsequent processing such as displaying a superimposed image or using the same for further image processing.

Although the embodiment of the present invention has been described above, the image processing method and the image processing apparatus according to the present invention are not limited to the above-described embodiment. For example, in the above embodiment, the image data is represented by luminance data, saturation data, and hue data.
The present invention is not limited to this, and the present invention can be similarly applied to a case where image data is represented by the RGB system (red, green, and blue pixel value data). In this case, the above-described transparency specification value and translucency specification value are assigned to data of a color that has little effect on the image due to the decrease in the number of gradations, and transmittance control in the translucency processing is performed using data of another color. And it is sufficient.

The present invention is applied not only to image data including three parameters for specifying a pixel by luminance, saturation, hue, and RGB, but also to image data for specifying a pixel by two parameters. be able to. In this case, one of the parameters is assigned a transparency specification value and a translucency specification value, and the superimposition and a distinction between transparent and translucent are designated,
The transmittance control in the translucent processing may be performed by the other parameter. That is, the present invention
If the image is represented by one or more parameters,
It can be applied to any form of image data.

Further, in the above embodiment, two images are superimposed, but three or more images may be superimposed. For example, the image processing apparatuses of FIG.
Each image processing device uses output luminance data Y, output chroma data Cb, and output hue data Cr from the preceding image processing device as input luminance data YB, chroma data CbB, and hue data CrB of a low-priority image. And Then, the data YA, CbA, and CrA of the high-priority image to be superimposed are supplied to the respective image processing devices, and the superimposition processing is executed as described above. This makes it possible to perform a process of sequentially superimposing three or more images.

[0059]

As described above, according to the present invention, one of the parameters representing each pixel of one image includes information for designating transparency or translucency, and thereby, a pixel designated as translucent. The other parameter is information specifying the transmittance of the pixel in the other image, and the pixel in the other image or the pixel in the other image is transmitted according to the parameter of each pixel. Either translucent pixels at a rate or pixels obtained by superimposing pixels of both images are output, so data for specifying transparency or non-transparency is input separately from image data. The normal α blending process, the transparent process, and the translucent process can be performed on a pixel-by-pixel basis without the necessity of performing. As a result, an effect is obtained that the amount of input data required for the superimposition processing of a plurality of images can be reduced and the input data bandwidth can be narrowed.

Further, according to the present invention, when there are two or more other parameters for specifying the transmittance, the transmittances of the different parameters of the pixels in the other image are respectively specified by those parameters. Then, the translucent process for each parameter is performed by them, so that the translucent process for controlling the transmittance independently for the parameters specifying each pixel such as luminance and color can be performed. it can.

According to the fifth aspect of the present invention, as described above, the process of superimposing each pixel in any mode of transparent, translucent, or superimposing includes a judging means for making a judgment based on the parameter, This is realized by a selection unit that selects the use data based on the determination, and a calculation unit that performs the calculation of the transparent processing, the translucent processing, or the superposition processing based on the result of the determination and the selection.

According to the sixth aspect of the present invention, since the image mixing ratio in the superimposition is set to a predetermined constant, the input data amount necessary for the superimposition processing of a plurality of images can be further reduced. The width can be further reduced.

According to a seventh aspect of the present invention, the image processing apparatus according to any one of the third to sixth aspects is provided in a plurality of stages, and the input to the second and subsequent image processing devices is set to the preceding image processing apparatus. Since the output of the processing device and the data of the image to be further superimposed were obtained, the image processing device of the second stage, the third stage,... Is output, and an image in which the image of the number of stages + 1 is superimposed is output from the image processing device at the last stage.
Therefore, by providing the image processing device as required, an effect is obtained that three or more images can be superimposed.

According to the invention of claim 8 or 9 ,
The translucent processing of the superimposition processing can be realized with a small amount of input data.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an image processing apparatus according to an embodiment of the present invention.

FIG. 2 shows blenders BL1 and B in the image processing apparatus.
FIG. 3 is a diagram illustrating an internal configuration of L2 and BL3.

FIG. 3 is a flowchart showing a superimposition processing procedure for each pixel by the image processing apparatus.

FIG. 4 is a diagram illustrating a configuration of a conventional image processing apparatus that performs image superimposition processing.

[Explanation of symbols]

BL1, BL2, BL3 Blender DE decoder SE1, SE2 Selector bl1, bl2, bl4 Selector bl3 Arithmetic unit YA, CbA, CrA (High priority image) data YB, CbB, CrB (Low priority image) Image data Y output Luminance data Cb output saturation data Cr output hue data

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06T 1/00 G09G 5/377 H04N 1 / 387,5 / 265

Claims (9)

(57) [Claims] 1. An image processing method for superimposing two images in which each pixel is represented by a plurality of parameters, wherein each pixel is transparent or translucent as one of parameters representing each pixel of one image. Is included, and another parameter representing a pixel that specifies to be translucent by the parameter is information that specifies the transmittance of a pixel in the other image. When specifying transparency, the pixel in the other image is a pixel after superimposition, and when the parameter specifies translucency, the pixel in the other image is translucent at the transmittance specified by the other parameter. The superimposed pixel is regarded as a pixel after superimposition, and when neither the transparent nor translucent is specified for the parameter, the pixel and the pixel in the other image are superimposed. An image processing method characterized by the Align was pixels and pixel after superimposition. 2. The image processing method according to claim 1, wherein when the other parameters are two or more, the transmittance specified by each of the parameters is set to the transmittance of a different parameter representing a pixel in the other image. An image processing method, wherein when the pixels in the other image are made translucent, the different parameters are made translucent at the respective transmittances specified by the other parameters. 3. An image processing apparatus for superimposing two images in which each pixel is represented by a plurality of parameters, wherein one of parameters representing each pixel specifies that the pixel is transparent or translucent. And image data of another parameter representing a pixel designating translucency by the parameter as information for designating the transmittance of a pixel in the other image, and image data of the other image. Data input means for inputting, for each pixel, output a pixel in the other image when the parameter specifies transparency, and output a pixel in the other image when the parameter specifies translucency. When the parameter is not translucent or translucent, it is output in a translucent state at the transmittance specified by the other parameter. The image processing apparatus characterized by having processing means for outputting by superimposing the pixel in the other image. 4. The image processing device according to claim 3, wherein, when the other parameters are two or more, the data input unit sets the transmittance specified by each of the parameters to a pixel in the other image. When the pixels in the other image are made to be translucent, the processing means makes each of the different parameters translucent at each transmittance specified by the other parameter. An image processing apparatus characterized by the above-mentioned. 5. The image processing apparatus according to claim 3, wherein the processing unit determines whether each of the pixels is to be superimposed in a transparent, translucent, or superimposed manner based on the parameter. Means for selecting the other parameter when the superimposition mode determined by the determination means is translucent, and selecting a predetermined image mixing ratio otherwise, and when the superimposition mode is transparent Outputs a pixel in the other image, and outputs the pixel in the other image in a translucent state at a transmittance designated by a parameter selected by the selection means when the superimposition mode is translucent, When the superimposition mode is superimposition, there is provided an arithmetic unit for superimposing and outputting the pixel and the pixel in the other image at the image mixing ratio selected by the selection unit. An image processing apparatus characterized by the above-mentioned. 6. The image processing apparatus according to claim 5, wherein the image mixing ratio is a predetermined constant. 7. The image processing apparatus according to claim 3, wherein a plurality of image processing apparatuses are provided, and in the second and subsequent image processing apparatuses, the other image data input by each of the data input units is provided. An image processing apparatus comprising: an output from an image processing apparatus at a preceding stage; and image data to be further superimposed on an output image. 8. An image processing method in which each pixel superimposes two images represented by a plurality of parameters, wherein one of parameters representing each pixel of one image designates that each pixel is translucent. And the other parameter representing a pixel that specifies translucency by the parameter is information that specifies the transmittance of a pixel in the other image. For each pixel, the parameter is translucent. The image processing method according to claim 1, further comprising: setting a pixel in the other image in a semi-transparent state at a transmittance specified by the other parameter as a pixel after superimposition. 9. An image processing apparatus for superimposing two images in which each pixel is represented by a plurality of parameters, wherein one of parameters representing each pixel includes information designating that the pixel is translucent. At the same time, image data of another parameter representing a pixel designating translucency by the parameter as information for designating the transmittance of a pixel in the other image and image data of the other image are input. Data input means, and processing means for, for each pixel, when the parameter specifies translucency, make the pixel in the other image translucent at a transmittance specified by the other parameter and output the pixel. An image processing apparatus characterized by the above-mentioned.