JPH0765148A - Image processing method - Google Patents

Abstract

PURPOSE:To provide a method which composes one image of two images at a high speed with a small load on a processor and a method which restores the composite image to the original images. CONSTITUTION:Image data consisting of a pixel value array having elements corresponding to pixels, constituting an image, one to one, and a color look-up table for converting the elements of the array into color data are used and weight determined on the number of colors of a background image is added to the pixel values of an actual image to control the pixel values of the background image and actual image with the one pixel value array; and a dedicated color look-up table is generated to perform fast processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for creating an image in which a background image and a real image are combined, and a process for restoring an original image from an image in which a background image and an actual image are combined, at high speed. It is about the method.

[0002]

2. Description of the Related Art In recent years, a system equipped with a graphic terminal has been widely used. Along with this, applications that process various images have been developed, but image processing imposes a heavy load on the processor,
Reducing the load on the processor has become an important issue.

In contrast to the operation of synthesizing a partial image of a real image designated by a binary array having the same size as the real image on a background image and restoring the background image from the synthesized image, the conventional technique It is generally done like this. However, a background image, a real image, a binary array for designating a partial image of the real image, and a combining position are given as input data, and the image data is composed of a pixel value array and a color lookup table. To do.

FIG. 4 shows a flow of the above processing.
A conventional processing method will be described below with reference to the drawings. (Initialization processing) (Operation 1) In order to store the pixel value of the actual image and the pixel value of the background image in the same pixel value array, the pixel value of the actual image is changed so as not to overlap with the pixel value of the background image. .

Along with this, the color look-up table of the actual image is also changed. (Operation 2) The color lookup table created in operation 1 and the color lookup table of the background image are merged to create a color lookup table for a new composite image. (Image combining process) (Operation 3) To restore the original image, the difference data of the pixel value array whose contents are changed by the combining process is saved.

(Operation 4) The contents of the pixel value array created in operation 1 are copied to the designated position.

At this time, the content of the binary array for designating the partial image is referred to, and only the element whose element value is 1 is copied. (Original Image Restoration Process) (Operation 5) Using the difference data stored in Operation 3, the element values of the pixel value array changed in Operation 4 are restored.

When the real image is re-composed at another position on the background image, the compositing position is changed and the above-mentioned image composition processing and original image restoration processing are repeated, thereby performing no initialization processing. Image composition can be performed.

[0009]

The conventional method has the following drawbacks.

In order to restore the background image after the combining process, it is necessary to create difference data in the combining process. Further, since the synthesizing process requires an operation in units of pixels as shown by 4 in FIG. 4, this becomes a bottleneck and reduces the processing speed.

An object of the present invention is to provide a high-speed image processing method which does not require the above-mentioned difference data generation operation and partial image selection operation.

[0012]

[Means for Solving the Problems] 1 and a pixel forming an image
Designated by a binary array of the same size as the actual image, using the array that has the elements corresponding to 1 and the image data that is composed of the color lookup table for converting the elements of this array to the color data of the image. The partial image of the real image
An image processing method for realizing a function of synthesizing on a background image and a function of restoring a background image from an image synthesized by the previous period function, which is a weight added to a pixel value of an actual image from the number of colors of the background image. , A means for determining a mask value for a pixel value to which a weight is added based on the result of the previous term weight determining means, and a pixel value array of an actual image based on the result of the previous term weight determining means. By means for converting into a pixel value array of an image, means for creating a pixel value array obtained by combining the pixel value array converted by the pixel value converting means and the pixel value array of the background image, and the previous pixel value array combining means A means for creating a color lookup table for converting the elements of the created pixel value array into color data of the composite image, and converting the elements of the pixel value array before composition to the color data of the background image; And means for restoring the image before combining the pixel value sequence prepared based on the mask value determined by the mask value determining means by the pixel value sequence combining means is used.

[0013]

With the above structure, a method is provided in which the pixel value arrays of the background image and the real image are physically placed in the same space, but they are logically divided and operated by a simple logical operation. Therefore, image synthesis and restoration processing can be performed at high speed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a pixel value array is logically divided into a plurality of two.
Treated as consisting of a value array. The number of binary arrays required to form each pixel value array is determined by (Equation 1) based on the number of colors of the image.

[0015]

[Equation 1]

Here, C represents the number of colors of the image, and N represents the number of binary arrays required to form the image. Hereinafter, this value is referred to as the image depth.

The pixel value array of the image in which the background image and the partial image are combined is treated in the same manner. However, in the image combined by using the processing method according to the present invention, the binary array forming the pixel value array is the background. It is different from the conventional method in that the image part and the partial image part are clearly separated.

Separation of the binary array is realized by adding a certain weight to the pixel value of the partial image. The weight is determined by (Equation 2) based on the depth of the background image. To be done.

[0019]

[Equation 2]

Here, N represents the depth of the background image, and W represents the weight added to the pixel value of the actual image. Further, the specific pixel value of the partial image is determined by (Equation 3) based on this weight.

[0021]

[Equation 3]

Here, W is a weight, Po is a pixel value of the original partial image, P is a pixel value of the partial image to which the weight is added, x, y
Indicates the subscript of the pixel value array.

The separation of the pixel value array of the composite image into the background image portion and the partial image portion means that the drawing processing for the partial image portion is performed independently of the background image portion by the drawing operation in plane units. Since this is possible, the processing load is reduced.

2 constituting the background image part or the partial image part
The value array is selected using the mask value obtained by (Equation 4).

[0025]

[Equation 4]

At this time, the value of each digit when the mask value is represented by a binary number becomes an element for determining the binary array to be selected. Here, W is a weight and M is a mask value.

FIG. 2 shows a process of generating a pixel value from a binary array of constituent elements after performing a drawing process on a partial image part in a pixel value array of a logically divided composite image. There is. The value of the element of the pixel value array configured from the binary array is determined by (Equation 5).

[0028]

[Equation 5]

Here, N is the depth of the composite image, BAn is the nth binary array forming the pixel value array, x, y are the subscripts of the binary array, and P is the coordinate (x, y) of the composite image. Shows the pixel value of.

FIG. 1 shows a processing flow using the method of the present invention. A conventional processing method will be described below with reference to the drawings. (Initialization Processing) (Operation 1) A partial image is generated from the input real image and binary array for specifying the partial image.

(Operation 2) Based on the number of colors of the background image, the weight to be added to the pixel value of the partial image is determined by (Equation 1) and (Equation 2).

(Operation 3) Based on the weight determined in Operation 2, the mask value of the binary array forming the background image is determined by (Equation 4).

(Operation 4) Based on the weight determined in operation 2, the pixel value of the partial image generated in operation 1 is changed. The specific pixel value is determined by (Equation 3). Further, the value of the color lookup table is also changed corresponding to the pixel value changed here.

(Operation 5) A color look-up table for the composite image is created based on the color look-up table of the input background image and the color look-up table of the partial image obtained in the operation 4. The procedure of creation is as follows.

The color look-up table of the background image is copied for the pixel values for which all the element values of the binary array which are not designated by the mask value are zero.

For other pixel values, the pixel value calculated when all the element values of the binary array designated by the mask value are 0 in the binary array which constitutes the pixel value. Thus, the corresponding element is copied from the color look-up table of the partial image whose pixel value has been converted. (Image Compositing Process) (Operation 6) In the binary array forming the pixel value array of the partial image obtained in Operation 4, the one specified by the mask value obtained in Operation 3 is input to the background image and combined. Copy to position. (Original Image Restoration Process) (Operation 7) Operation 3 is performed on the element whose content is updated in Operation 6 in the binary array forming the pixel value array of the composite image.
Clear the contents based on the mask value obtained in.

When synthesizing the real image again at another position on the background image, as in the case of the conventional method,
By changing the synthesizing position and repeating the above-described image synthesizing process and original image restoring process, it is possible to perform image synthesizing without performing the initialization process.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows the flow of data when performing image synthesis and restoration processing. 1 to 6 are input data,
In the initialization processing, internal data of 8, 11, 12, and 13 are generated from these. First, partial images 4, 5, 6 to 7, 8 are generated. At this time, the pixel value of the pixel not designated by the binary array is set to a meaningless value (here, *). If the number of colors in the partial image is less than the actual image,
The pixel values are changed so that they are serial numbers, and the values in the color lookup table are also changed accordingly. Next, based on the number of colors of the background image, (Equation 1), (Equation 2), (Equation 4)
According to the depth of the background image, the weight added to the partial image,
Determine the mask value for the background image. Then, according to (Equation 3), the pixel value array of 9 is converted into 11. Along with this, the value of the color lookup table of 10 is also changed to 12. Finally, 13 color lookup tables are created from 3 and 12 color lookup tables.

With the above, the initialization process is completed. In the image composition process, 15 pixel value arrays are generated from 1, 2, 11 inputs. The pixel value after composition can be determined by (Equation 6),

[0040]

[Equation 6]

Among the binary arrays forming the pixel value array of the partial image, the one specified by the mask value of 8 is copied to the specified position of the pixel value array of the background image, whereby high speed is achieved. Processing can be performed. Here, PH is the pixel value array of the background image, PB is the pixel value array of the partial image,
P is the pixel value array of the composite image, xG, yG are the image composition positions,
x and y are subscripts for the elements of the pixel value array to be obtained, wH is the width of the background image, hH is the height of the background image, wB is the width of the partial image, and hB is the height of the partial image. This is the end of the image synthesizing process.

In the original image restoration process, 14 pixel value arrays are generated from 8 and 15 inputs. This is done by clearing the contents of what is specified by the mask value of 10 in the binary array that constitutes the array of 15 pixel values. This is the end of the original image restoration process.

[0043]

As described above, according to the present invention, since the image synthesizing process and the original image restoring process are realized only by the operation on a plane basis, the conventional method requiring the operation on a pixel value basis. On the other hand, the load on the processor can be reduced.

[Brief description of drawings]

FIG. 1 is a process flow chart using the method of the present invention.

FIG. 2 is a diagram showing a logical configuration of a pixel value array and a process of extracting pixel values.

FIG. 3 is a data flow diagram of an embodiment using the method of the present invention.

FIG. 4 is a processing flow chart according to a conventional technique.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H04N 1/387 9/75 9191-5L G06F 15/68 310 J

Claims (1)

[Claims] 1. An image data comprising an array having elements corresponding to pixels constituting an image in a one-to-one correspondence and image data composed of a color lookup table for converting the elements of the array into color data of the image, An image for realizing a function of synthesizing a partial image of a real image specified by a binary array of the same size as the real image on the background image and a function of restoring the background image from the image synthesized by the previous period function A processing method, which determines a weight to be added to a pixel value of an actual image from the number of colors of the background image, and a mask value for the weighted pixel value based on the result of the previous weight determination means. Means, a means for converting the pixel value array of the actual image into a pixel value array of the composite image based on the result of the weight determining means, a pixel value array converted by the pixel value converting means, and a pixel value array of the background image. From this To convert the elements of the pixel value array created by the previous pixel value array combining means into color data of the combined image, and to convert the elements of the pixel value array before combining to the background image color. A means for creating a color look-up table for converting into data and a pixel value array created by the pixel value array synthesizing means on the basis of the mask value decided by the mask value deciding means in the previous period to restore an image before synthesis. An image processing method comprising: