JP3177306B2 - Image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing device for expanding image data.

[0002]

2. Description of the Related Art Block coding is one method of data compression. For example, according to the JPEG standard, image data composed of a luminance signal (hereinafter, for example, Y) and a chrominance signal (for example, Pb, Pr) is divided into a data block of 8 × 8 pixels horizontally and vertically for each signal. DCT transformation, quantization and Huffman coding are performed for each data block, and data compression is performed.

[0003] Y compresses sample data of all pixels,
Pb and Pr compress the sub-sampled data sub-sampled in the horizontal direction at half the sampling frequency of Y. In order to compress the data of Y, the spatial block necessary for compressing the data on the monitor may be 8 × 8 pixels, but to compress the data of Pb and Pr, the spatial block may be formed of 16 × 8 pixels. (This 16x
An 8-pixel spatial block is 8 × 8 by sub-sampling.
It becomes a data block of pixels, and the data block of 8 × 8 pixels is compressed), and the spatial block on the monitor must be 16 × 8 pixels horizontally and vertically. Therefore, unless the image data has an image size of 16m × 8n (where m and n are natural numbers) pixels,
Data compression cannot be performed.

Accordingly, when performing data compression, extra image data of an unspecified area is added to
It was necessary to convert to an image size of 6 m × 8 n pixels.

[0005]

When the compressed data compressed as described above is decompressed and stored in the storage means, not only the image data but also the image data of the extra non-designated area is decompressed and stored. There is a disadvantage that it is stored in the memory. Therefore, it is necessary to adopt a configuration in which extra image data of an unspecified area is not stored after data expansion.

[0006]

According to the present invention, there is provided an image processing apparatus which expands data in units of spatial blocks of M × N pixels (where M and N are natural numbers). The image data of the compression / expansion area composed of an integer number of the spatial blocks obtained by adding the image data of the non-designated area to the data as necessary is compressed in advance in units of the spatial blocks, and the generated compressed data is recorded. A recording medium, decompression means for decompressing the compressed data read from the recording medium in units of spatial blocks, and a pixel corresponding to each of the image data output by the decompression means in a predetermined order is a designated area or designated area. Area determination means for determining whether the image data belongs to an outside area and prohibiting writing of image data corresponding to pixels belonging to the outside area; Based on the determination of, and storage means for storing only the image data of the designated area, an image processing apparatus comprising disposed respectively.

[0007]

According to the image processing apparatus of the present invention, when storing image data in a compression / expansion area generated by expanding compressed data read from a recording medium in units of spatial blocks, image data output in a predetermined order Determine whether the pixel corresponding to each of the specified area or non-designated area,
Writing of image data corresponding to pixels belonging to the non-designated area is prohibited, and only the image data of the designated area is stored in the storage means.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention;
Example 2 and Example 2 will be described. [1] First Embodiment A luminance signal (hereinafter, for example, Y) and a chrominance signal (hereinafter, for example, P)
(b, Pr) will be described.

As described above, a spatial block on the monitor, which is a processing unit for data compression, is 16 × 8 horizontally and vertically.
In order to compress data in units of spatial blocks, horizontal and vertical 16 m × 8 n pixels (m, n
Is a natural number). As shown in FIG. 2, image data (for example, horizontal / vertical 1590 × 795) of a designated area that the operator recognizes as a target image
When the image size of the pixel) is divided into the above-mentioned integer number of space blocks (16 m × 8 n pixels), a pixel having a fraction of 6 pixels in the horizontal direction and 3 pixels in the vertical direction is generated (m
= 99, n = 99).

Therefore, in order to compress the image data of the designated area, the image data of the non-designated area, which is a dummy of 10 pixels in the horizontal direction and 5 pixels in the vertical direction, respectively, ) Must be added to form a compression / decompression area (image size of 1600 × 800 pixels) consisting of an integer number of spatial blocks (m = 100, n = 100). The image data in the compression / expansion area is compressed in units of spatial blocks.

However, the image data in the non-designated area is temporary data provided to supplement the image data in the designated area and expand the image data in the compression / expansion area for an integral number of spatial blocks. And the same image information as the image data of the outermost line adjacent to the image data in the non-designated area. In the first embodiment, compressed data recorded in advance on a recording medium after data compression as described above is expanded.

The function of each functional block of the first embodiment will be described below with reference to FIG. FIG. 1 is a functional block diagram of the first embodiment, and FIG. 2 is a diagram showing image data of the first embodiment. The recording medium 1 is, for example, an optical disk. As described above, the image data of the non-designated area, which is dummy data, is added to the image data of the designated area, and the image data of the compression / decompression area, which is just an integer number of space blocks, is added. The compressed data obtained by data compression is recorded in the first area in advance.

The recording medium 1 has size information of the image data in the designated area and the compression / decompression area (designated area 1).
590 x 795 pixels, compression / expansion area 1600 x 800
Pixel) is recorded in the second area. The reproducing means 2 is, for example, an optical disk drive, and reproduces compressed data recorded in the first area of the recording medium 1 and size information recorded in the second area, and decompresses the compressed data. 3 and the size information to the area determination means 7.

The decompression means 3 decompresses the compressed data supplied from the reproduction means 2 in space block units. The image data of the compressed / expanded area to be expanded is sequentially supplied to the storage means 4, and further, a pixel corresponding signal indicating a pixel corresponding to each of the image data of the sequentially expanded / expanded area is determined by the area determining means 7, To the means 8 and the write address generating means 9.

For example, since the decompression means 3 performs data decompression on a space block basis, the order of image data in the compression / decompression area to be data decompressed is Y corresponding to 16 × 8 pixels with respect to the first space block. Of the Pb image data (the data expansion of the 8 × 8 pixel data block is repeated twice), and the Pb image data corresponding to the 8 × 8 pixel is data expanded (the data expansion of the 8 × 8 pixel data block is performed). Once), and data expansion of the Pr image data corresponding to 8 × 8 pixels is performed (data expansion of a data block of 8 × 8 pixels is performed once). By repeating this for each spatial block, data decompression is performed.

The order of output of the image data by the decompression means 3 is not limited to the order in which Y is repeated 16 × 8 pixels, Pb is 8 × 8 pixels, and Pr is 8 × 8 pixels. In some cases, after temporarily storing these data in a built-in data buffer, for example, Y is output for one image,
Next, Pb can be output for one image, and Pr can be output for one image. Therefore, it is possible to output image data in various orders, and it goes without saying that they are included in the present invention.

The area determining means 7 determines that the image data of the compression / expansion area is determined in a predetermined order (for example, Y is 16 ×
8 pixels, Pb is repeated as 8 × 8 pixels, and Pr is repeated as 8 × 8 pixels). Therefore, the pixels corresponding to the image data in the compression / decompression area, which are decompressed by the decompression means 3 and sequentially output, are output. Based on the pixel corresponding signal to be represented and the size information of the designated area and the compression / expansion area supplied from the reproducing unit 3, it is detected which pixel in the compression / expansion area corresponds to each pixel indicated by the pixel correspondence signal, It is determined whether the detected pixel belongs to a designated area or a non-designated area.

For example, the pixel corresponding signal is a continuous square wave, and one cycle of the square wave corresponds to each pixel. That is,
The image data of the compressed / expanded area after data expansion is supplied to the storage means 4 in the order of repeating Y for 16 × 8 pixels, Pb for 8 × 8 pixels, and Pr for 8 × 8 pixels. The first 16 × 8 periods of the square wave indicating the pixels indicate the Y pixels of the first spatial block, the next 8 × 8 periods indicate the Pb pixels of the first spatial block, and the next 8 × 8 periods
× 8 periods indicate Pr pixels of the first spatial block,
The next 16 × 8 period indicates the Y of the next space block, and so on. For each cycle of this square wave (pixel corresponding signal), it detects which pixel in the compression / expansion area corresponds to, and determines whether the detected pixel belongs to a designated area or a non-designated area. I do.

Further, the area determination means 7 outputs a write enable signal for writing image data (image data of the specified area) corresponding to the pixel determined to belong to the specified area to the storage means 4, 8 to supply
The write signal generation unit 8 is supplied with a write inhibit signal indicating that image data (image data of the non-designated area) corresponding to pixels determined to belong to the non-designated area is not written into the storage unit 4.

Further, the area judging means 7 supplies the write address generating means 9 with a pixel detection signal indicating that each pixel indicated by the pixel correspondence signal corresponds to a position in the compression / expansion area. I do. The write signal generation means 8 outputs a write permission signal or a write inhibition signal from the area determination means 7 to each pixel (Y pixel, Pb pixel, Pr pixel) indicated by the pixel correspondence signal obtained by the decompression means 3. Therefore, when a write enable signal is supplied, a write signal is supplied to the storage unit 4 so as to write image data (image data of the designated area) corresponding to the pixel into the storage unit 4. When a write inhibit signal is supplied, no write signal is supplied to the storage means 4 to inhibit writing of image data (image data of an undesignated area) corresponding to the pixel into the storage means 4.

The write address generating means 9 outputs each pixel (Y pixel,
Area determination means 7 for the Pb pixel and the Pr pixel).
Since a pixel detection signal indicating which position of the compression / expansion area corresponds to the pixel is supplied, the write address of the image data of the compression / expansion area corresponding to each pixel indicated by the pixel correspondence signal is determined based on the pixel detection signal. Then, the write address is supplied to the storage unit 4.

The storage means 4 stores the compression / decompression area supplied from the decompression means 3 at the storage position indicated by the address generated by the write address generation means 9 at the timing when the write signal is generated by the write signal generation means 8. Of the image data, only the image data of the designated area is stored. The storage unit 4 supplies the stored image data of the designated area to the video processing unit 5 in accordance with a read address generated by a read address generation unit 10 described later.

The read address generating means 10 supplies a read address to the storage means 4 in order to read the image data of the designated area stored in the storage means 4. The video processing unit 5 converts the image data of the designated area read from the storage unit 4 into a Hi-Vision signal. Display means 6
Is a high-definition monitor, for example.
Based on the supplied Hi-Vision signal, an image of the corresponding designated area is displayed.

Therefore, the area determining means 7 is provided
In order to prohibit writing of the image data of the non-designated area into the storage means 4 among the image data of the compression / decompression area, the image data (dummy data) of the non-designated area is stored after the data expansion. Not remembered in
Therefore, it is not necessary to display the image (dummy) of the non-designated area on the screen of the display means.

The image data in the non-designated area may be added to any of the four corners of the image data in the designated area. Further, when the image data of the designated area is just the image size of an integer number of space blocks, it is not necessary to add the image data of the non-designated area, and the image data of the designated area becomes the image data of the compression / decompression area. Needless to say. Further, in this case, it goes without saying that the image data write inhibit function in the area determination means 7 does not operate.

Furthermore, the compression / decompression area is not limited to the area of the smallest integer number of spatial blocks including the designated area, but may be any area including the designated area and an area of an integer number of spatial blocks. It goes without saying that it is good. In the first embodiment, Y and Pb and Pr subsampled in the horizontal direction at half the sampling frequency of Y have been described.
r may be sampled at an arbitrary sampling frequency (eg, sampled at the same sampling frequency as Y, for example, sub-sampled at a sampling frequency of の of the Y sampling frequency), and so on. Needless to say, the present embodiment can be implemented even with such a configuration.

The luminance signal and the color difference signal are not limited to Y, Pb, and Pr, respectively, and may be appropriately selected. [2] Second Embodiment In the first embodiment described above, when data is compressed, dummy image data of a non-designated area is added to image data of a designated area, and compression is performed for exactly an integer number of space blocks. The compressed data obtained by compressing the data into the image data of the decompression area is recorded in advance on the recording medium. However, the image data of the designated area does not always exist from the beginning. In some cases, an area to be specified is specified.

Therefore, in the second embodiment, if the image data of the designated area designated by the operator is not 16 m × 8n (m and n are natural numbers) pixels, the data size is 16 m × 8 m for data compression. Since an image size of 8n pixels is required, 16m × 8n including image data adjacent to the designated area (image data of the non-designated area, hatched portion in FIG. 4)
Compressed data obtained by compressing the image data in the compression / expansion area of 16 m × 8 n pixels is recorded on a recording medium.

Therefore, in the first embodiment, the image data in the non-designated area is dummy data added when data is compressed. In the second embodiment, the image data in the non-designated area is the dummy data. This is data having image information included when image data is specified, and is different from dummy data (see FIG. 4). Hereinafter, a case where the operator specifies a desired area will be described with reference to FIG. However, FIG.
1 and FIG. 1 have common functional blocks, and the same blocks will be denoted by the same reference numerals and redundant description will be omitted.

As in the first embodiment, a case where image data is constituted by using a luminance signal (for example, Y) and a color difference signal (for example, Pb, Pr) will be described. Therefore, the space block has 16 pixels in the horizontal direction and 8 pixels in the vertical direction. The scanner 11 has an arbitrary image size (for example, 2200 × 12
(00 pixels) and outputs the read original image data to the storage unit 4.

The designating means 12 has operating means (not shown) for designating a portion to be extracted from the original image displayed on the high-definition monitor as a designated area, and a designated area formed by operating the operating means. Is supplied to the video processing means 5. Therefore, the operator operates the operation unit while watching the frame multiplexed displayed on the high-definition monitor, changes the area size of the frame, and specifies the area (designated area) represented by the frame.

The designating means 12 determines whether the designated area has an image size of an integral number of spatial blocks. If the designated area is not an image size of an integral number of spatial blocks,
An area (compression / expansion area) for an integer number of spatial blocks including the designated area is specified, and a read address corresponding to the compression / expansion area is supplied to the storage means 4. Further, the designation unit 12 supplies the recording unit 14 with the size information of the designated area and the compression / decompression area.

The compression means 13 reads out the image data in the compression / decompression area from the address designated by the designation means 12 and compresses the data in units of spatial blocks to generate compressed data. The recording unit 14 is, for example, an optical disk drive, and records the compressed data compressed by the compression unit 13 on the recording medium 1. Furthermore, the size information (1590 × 795 pixels) of the image data of the designated area and the size information (1600 × 800) of the image data of the compression / decompression area
Pixel) is recorded on the recording medium 1.

As described above, the compressed data and the size information recorded on the recording medium 1 are reproduced in the same manner as in the first embodiment, the compressed data is decompressed by the decompression means 3, and the output decompression area is output. Out of the image data of the non-designated area based on the size information, the area determination means 7 prohibits writing of the image data of the non-designated area into the storage means 4. And only the image data of the designated area is stored in the storage means 4. Therefore, it is not necessary to display the image (image information) of the non-designated area on the screen of the display unit 6.

The image data in the non-designated area may exist anywhere in the four corners of the image data in the designated area. When the image data in the designated area has an image size of an integral number of space blocks, the image data in the compression / expansion area does not need to include the image data in the non-designated area. It goes without saying that the image data becomes. Further, in this case, it goes without saying that the image data write inhibit function in the area determination means 7 does not operate.

Furthermore, the compression / decompression area is not limited to an area corresponding to the smallest integer number of space blocks including the designated area, but may be any area including the designated area and an area corresponding to an integer number of space blocks. It goes without saying that it is good. In the second embodiment, Y and Pb and Pr subsampled in the horizontal direction at half the sampling frequency of Y have been described.
r may be sampled at an arbitrary sampling frequency (eg, sampled at the same sampling frequency as Y, for example, sub-sampled at a sampling frequency of の of the Y sampling frequency), and so on. Needless to say, the present embodiment can be implemented even with such a configuration.

The luminance signal and the color difference signal are not limited to Y, Pb, and Pr, respectively, and may be appropriately selected. still,
In the above-described first and second embodiments, the image data of the compression / expansion area is supplied to the storage unit 4. Since no write signal is generated for the image data in the outside area, the image data in the non-designated area is not stored in the storage means 4 and only the image data in the designated area is stored in the storage means 4. 4
However, the configuration for supplying only the image data of the designated area is not limited to this, and the following configuration may be employed, and such a configuration is included in the present invention.

FIG. 5 is a functional block diagram of a main part of the configuration described below. For example, the first gate means 15 is provided at the output destination of the expansion means 3, and the second gate means 16 is provided on the branch line of the pixel corresponding signal supplied from the expansion means 3. When a pixel-corresponding signal is supplied from the decompression means 3, the area determination means 7 determines that a pixel corresponding to each of the image data of the compressed and decompressed area supplied to the first gate means 15 belongs to the designated area. It is determined whether the pixel belongs to a pixel or a non-designated area.

If it is determined that the pixel belongs to the non-designated area, the area determining means 7 outputs a prohibition signal for prohibiting the generation of image data corresponding to the pixel to the first gate means 15 and the second gate means 16. To supply. If it is determined that the pixel belongs to the designated area, the area determination unit 7 supplies a generation signal to generate image data corresponding to the pixel to the first gate unit 15 and the second gate unit 16.

The first gate means 15 closes the gate when the inhibit signal is supplied and does not pass the image data, but opens the gate only when the generated signal is supplied and passes the image data. The first gate means 15 outputs only the image data of the designated area. The second gate means 16 closes the gate when the prohibition signal is supplied, does not pass the pixel corresponding signal, and opens the gate only when the generated signal is supplied, and passes the pixel corresponding signal.
From the second gate means 16, only a pixel corresponding signal indicating a pixel belonging to the designated area is output.

The area judging means 7 supplies only the write enable signal to the write signal generating means 8 and supplies a pixel detection signal to the write address generating means 9. The write signal generation means 8 supplies a write signal to the storage means 4 for each pixel (pixel in the designated area) indicated by the pixel correspondence signal obtained from the second gate means 16, and the write address generation means 9 A write address is supplied to each pixel (pixel in the designated area) indicated by the pixel correspondence signal obtained from the second gate means 16.

Therefore, only the image data of the designated area is supplied to the storage means 4, and only the image data of the designated area is stored. Note that the function (circuit) blocks of both embodiments described above may be configured by software or hardware as necessary, and it goes without saying that the present invention also includes some forms. .

Furthermore, the above-described embodiments are merely examples of the present invention, and various changes can be made as necessary. The present invention described in the claims encompasses all such changes. Things.

[0044]

Therefore, according to the present invention, when storing the decompressed image data in the storage means, it is possible to store only the image data in the designated area without storing the extra image data in the non-designated area. Yes, the effect is great.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a first embodiment of the present invention.

FIG. 2 is a diagram showing an image according to the first embodiment of the present invention.

FIG. 3 is a functional block diagram of a second embodiment of the present invention.

FIG. 4 is a diagram showing an image according to a second embodiment of the present invention.

FIG. 5 is a functional block diagram of one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording medium 3 Decompression means 4 Storage means 7 Area determination means

Claims (1)

(57) [Claims] 1. An image processing apparatus for expanding data in units of spatial blocks of M × N pixels (where M and N are natural numbers), wherein image data of a designated area of an arbitrary size is added to image data of a non-designated area as necessary. The image data of the compression / expansion area composed of an integer number of the spatial blocks to which data has been added is compressed in advance in units of the spatial blocks, and a recording medium for recording the generated compressed data, and read from the recording medium Decompression means for decompressing the compressed data in units of spatial blocks; and determining whether pixels corresponding to each of the image data output in a predetermined order by the decompression means belong to a designated area or a non-designated area. Area determination means for prohibiting writing of image data corresponding to pixels belonging to the area, and image data of a designated area based on the determination by the area determination means. An image processing apparatus comprising storage means for storing data only.