JPH0654207A - Image processor - Google Patents

Abstract

PURPOSE:To provide an image processor which never records the unnecessary dummy data or image information after the expansion of data. CONSTITUTION:A compressed data read out of a recording medium 1 are expanded by an expanding means 3 for each space block and turned into the image data on the compressed/ expanded area. When these image data are stored, an area deciding means 7 decides whether the picture elements corresponding to each of the image data which are outputted in the prescribed order belong to the designated areas or the non-designated areas. Then the means 7 inhibits the writing of the image data accordant with the picture elements belonging to the non-designated areas. Thus only the image data on the designated areas are stored in a storage means 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for decompressing 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, Y, for example) and a color difference signal (hereinafter, Pb, Pr, for example) is divided into data blocks of horizontal and vertical 8 × 8 pixels for each signal. Data is compressed by DCT transformation, quantization and Huffman coding in units of data blocks.

Y compresses sample data of all pixels,
Pb and Pr compress the sub-sampled data obtained by sub-sampling in the horizontal direction at a frequency half the Y sampling frequency. In order to compress Y, the spatial block required for data compression on the monitor may be 8 × 8 pixels, but in order to compress Pb and Pr, the spatial block is 16 × 8 pixels. (This 16x
Spatial block of 8 pixels is 8 × 8 by subsampling
It becomes a data block of pixels, and this data block of 8 × 8 pixels must be 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 16 m × 8 n (where m and n are natural numbers) pixels,
Data compression cannot be performed.

Therefore, when data compression is performed, the image data of the extra undesignated area is added to the image data to
It was necessary to convert to an image size of 6m x 8n 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 in the extra undesignated area is decompressed and stored in the storage means. It has the inconvenience of being stored in. Therefore, it is necessary to make a structure in which the extra image data of the non-designated area is not stored after the data expansion.

[0006]

An image processing apparatus according to the present invention is an image processing apparatus for decompressing data in units of spatial blocks of M × N (where M and N are natural numbers) pixels, and an image of a designated area of an arbitrary size. The image data of the compression / expansion area, which is formed by adding the image data of the non-designated area to the data if necessary, is compressed in advance in the space block unit, and the generated compressed data is recorded. A recording medium, a decompressing unit that decompresses the compressed data read from the recording medium on a spatial block basis, and a pixel corresponding to each of the image data output in a predetermined order by the decompressing unit is a designated area or designation. Area determining means for determining whether the pixel belongs to an outside area and prohibiting writing of image data corresponding to pixels belonging to the non-designated 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]

The image processing apparatus of the present invention outputs the image data output in a predetermined order when storing the image data of the compression / expansion area generated by decompressing the compressed data read from the recording medium in units of spatial blocks. Determine whether the pixel corresponding to each of the belonging to the designated area or non-designated area,
Writing of image data corresponding to the 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]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First embodiment of the present invention applied to a compression processing apparatus
The embodiment and the second embodiment will be described. [1] First Embodiment Luminance signal (hereinafter, for example, Y), color difference signal (hereinafter, for example, P)
The case where the image data is constructed using (b, Pr) will be described.

As described above, the spatial block on the monitor, which is a processing unit for data compression, is 16 × 8 horizontally and vertically.
Since pixels must be used, 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 of a designated area (for example, horizontal and vertical 1590 × 795) that the operator recognizes as a target image.
When the image size of pixels is divided into the above-mentioned integer number of spatial blocks (16 m × 8 n pixels), there are 6 pixels in the horizontal direction and 3 pixels in the vertical direction, which are fractional pixels (m
= 99, n = 99).

Therefore, in order to compress the image data of the designated area, the image data of the non-designated area (the shaded portion) is a dummy of 10 pixels in the horizontal direction and 5 pixels in the vertical direction in the pixels corresponding to this fraction. ) Must be added to form a compression / expansion area (image size of 1600 × 800 pixels) that is exactly composed of an integral number of spatial blocks (m = 100, n = 100). The image data in the compression / decompression area is compressed in space block units.

However, the image data of the non-designated area is provisional data provided to supplement the image data of the designated area to the image data of the compression / expansion area for an integral number of spatial blocks. Of the image data, the image data of the outermost peripheral line adjacent to the image data of the non-designated area has the same image information. In the first embodiment, the compressed data previously compressed as described above and recorded on the recording medium 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 / expansion area that is just an integral number of space blocks is generated. The compressed data obtained by data compression is recorded in advance in the first area.

The recording medium 1 has size information of 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, reproduces the compressed data recorded in the first area of the recording medium 1 and the size information recorded in the second area, and expands the compressed data. 3 and the size information is supplied to the area determining means 7.

The decompression unit 3 decompresses the compressed data supplied from the reproduction unit 2 in units of spatial blocks. The image data of the compressed / expanded area to be expanded is sequentially supplied to the storage means 4, and further, the pixel determination signal for generating the pixel corresponding signal indicating the pixel corresponding to each of the image data of the expanded / compressed area to be sequentially expanded is generated. It is supplied to the means 8 and the write address generating means 9.

For example, since the decompression means 3 decompresses data in units of spatial blocks, the order of image data in the compression / decompression area for data decompression is Y corresponding to 16 × 8 pixels for the first spatial block. Image data is expanded (data expansion of a data block of 8 × 8 pixels is repeated twice), and image data of Pb corresponding to 8 × 8 pixels is expanded (data expansion of a data block of 8 × 8 pixels is performed). The image data of Pr corresponding to 8 × 8 pixels is decompressed (data decompression of a data block of 8 × 8 pixels is performed once). Data expansion is performed by repeating this for each spatial block.

The order of outputting the image data by the decompressing means 3 is not limited to the order in which Y is 16 × 8 pixels, Pb is 8 × 8 pixels and Pr is 8 × 8 pixels, and the decompressing means 3 is used. Depending on the data, after storing these data in the built-in data buffer, Y is output for one image,
Next, Pb can be output for one image and Pr can also be output for one image. Therefore, it is needless to say that the image data can be output in various orders, which are included in the present invention.

The area determining means 7 is arranged so that the image data in the compression / expansion area is transmitted in a predetermined order from the expansion means 3 (for example, Y = 16 ×).
8 pixels, Pb is output in the order of 8 × 8 pixels and Pr is repeated in the order of 8 × 8 pixels). Therefore, the pixel corresponding to each of the image data in the compression / expansion area that is expanded by the expansion unit 3 and sequentially output is selected. Based on the pixel corresponding signal and the size information of the designated area and the compression / expansion area supplied from the reproducing means 3, it is detected which position in the compression / expansion area each pixel indicated by the pixel corresponding signal corresponds to. It is determined whether the detected pixel belongs to a designated area or a pixel that does not belong to the designated area.

For example, the pixel corresponding signal is a continuous square wave, and one period of the square wave corresponds to each pixel. That is,
The image data of the compressed / decompressed area, which has been subjected to data decompression, 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 pixels of Pb of the first spatial block, and the next 8 × 8 periods.
× 8 cycles represent Pr pixels of the first spatial block,
The next 16 × 8 periods indicate Y of the next spatial block, and so on. For each cycle of this square wave (pixel corresponding signal), which position in the compression / expansion area the pixel corresponds to is detected, and it is determined whether the detected pixel belongs to the designated area or a pixel not designated. To do.

Further, the area determination means 7 sends a write permission signal to the effect that the image data (image data of the designated area) corresponding to the pixel determined to belong to the designated area is written in the storage means 4, the writing signal generation means. Supply to 8,
A write inhibit signal indicating that the image data corresponding to the pixels determined to belong to the non-designated area (image data of the non-designated area) is not written in the storage unit 4 is supplied to the write signal generation unit 8.

Further, the area determination means 7 supplies the write address generation means 9 with a pixel detection signal indicating to which position in the compression / expansion area each pixel indicated by the pixel correspondence signal corresponds. To do. The write signal generating means 8 writes a write enable signal or a write disable signal from the area determining means 7 for each pixel (Y pixel, Pb pixel, Pr pixel) indicated by the pixel corresponding signal obtained from the expanding means 3. Therefore, when the write enable signal is supplied, the write signal is supplied to the storage means 4 so as to write the image data (image data of the designated area) corresponding to the pixel in the storage means 4. Further, when the write inhibit signal is supplied, the write signal is not supplied to the storage means 4 in order to inhibit writing of the image data (image data of the undesignated area) corresponding to the pixel in the storage means 4.

The write address generating means 9 is provided for each pixel (Y pixel, which is indicated by the pixel corresponding signal obtained from the expanding means 3).
Area determining means 7 for Pb pixel and Pr pixel)
Since the pixel detection signal indicating which position in the compression / expansion area corresponds to the pixel is supplied, the write address of the image data in the compression / expansion area corresponding to each pixel indicated by the pixel correspondence signal is set based on the pixel detection signal. It is specified and the write address is supplied to the storage means 4.

The storage means 4 stores the compression / expansion area supplied from the expansion means 3 at the timing at which the write signal is generated by the write signal generation means 8 at the storage position indicated by the address generated by the write address generation means 9. Of the image data, only the image data of the designated area is stored. Further, the storage means 4 supplies the image processing means 5 with the stored image data of the designated area in accordance with the read address generated by the read address generating means 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 means 5 converts the image data of the designated area read from the storage means 4 into a high-definition signal. Display means 6
Is, for example, a high-definition monitor, and the video processing means 5
The image of the corresponding designated area is displayed based on the supplied high-definition signal.

Therefore, the area determination means 7 is the expansion means 3
Of the image data in the compression / expansion area decompressed in (1), it is prohibited to write the image data in the non-designated area to the storage means 4. Therefore, after the data decompression, the image data (dummy data) in the non-designated area is stored in the storage means 4. 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 of the non-designated area may be added to any of the four corners of the image data of the designated area. If the image data of the designated area has an image size of just an integer number of spatial 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 / expansion area. Needless to say. Further, in this case, it goes without saying that the image data write prohibition function in the area determination means 7 does not operate.

Furthermore, the compression / decompression area is not limited to the area of the smallest number of spatial blocks including the designated area, but may be any area as long as it includes the designated area and the area of the integral number of spatial blocks. It goes without saying that it is good. In the first embodiment, Y and Pb and Pr sub-sampled in the horizontal direction at a frequency half the sampling frequency of Y have been described.
r may be sampled at any sampling frequency (eg, sampled at the same sampling frequency as Y, eg, subsampled at a quarter of the Y sampling frequency), and so on. It goes without saying that 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 selected appropriately. [2] Second Embodiment In the first embodiment described above, when data compression is performed, image data of a non-designated area that is a dummy is added to the image data of the designated area, and compression is performed for just an integral number of spatial blocks. The compressed data that was compressed as the image data of the decompression area was recorded in the recording medium in advance. However, the image data of the designated area does not always exist from the beginning, and the image data of an arbitrary size is desired by the operator. In some cases, the area to be specified is specified.

Therefore, in the second embodiment, when the image data of the designated area designated by the operator does not have the image size of 16 m × 8 n (m and n are natural numbers) pixels, 16 m × for data compression. Since an image size of 8n pixels is required, 16m x 8n including the image data adjacent to the designated area (image data of the non-designated area, the shaded area in Fig. 4)
An image size of pixels is used, and compressed data obtained by data-compressing the image data in the compression / expansion area having a size of 16 m × 8 n pixels is recorded on a recording medium.

Therefore, in the first embodiment, the image data of the non-designated area is dummy data added when the data is compressed, but in the second embodiment, the image data of the non-designated area is the dummy data of the designated area. It is data having image information included when image data is designated, and is different from dummy data (see FIG. 4). A case where the operator designates a desired area will be described below with reference to FIG. However, FIG.
1 and FIG. 1 have common functional blocks, the same blocks will be given the same reference numerals and redundant description will be omitted.

Similar to the first embodiment, a case will be described in which image data is constructed using a luminance signal (eg Y) and color difference signals (eg Pb, Pr). Therefore, the spatial block has 16 pixels in the horizontal direction and 8 pixels in the vertical direction. The scanner 11 can display any image size (for example, 2200 × 12).
The original image data of (00 pixels) is read, and the read original image data is output to the storage unit 4.

The designating means 12 has an 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 the designated area formed by operating the operating means. The frame information corresponding to is supplied to the video processing means 5. Therefore, the operator operates the operation means while changing the area size of the frame while watching the frame displayed in multiplex on the high-definition monitor, and specifies the area (designated area) represented by the frame.

Further, the designating means 12 judges whether or not the designated area has an image size of an integral number of spatial blocks, and when the designated area is not an image size of an integral number of spatial blocks,
An area (compression / expansion area) corresponding to an integral number of space 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 designating means 12 supplies the size information of the designated area and the compression / decompression area to the recording means 14.

The compression means 13 reads the image data of the compression / decompression area from the address designated by the designation means 12, compresses the image data in space block units, and generates 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 of the image data of the designated area (1590 × 795 pixels) and the size information of the image data of the compression / expansion area (1600 × 800 pixels)
Pixels) are recorded on the recording medium 1.

As described above, the compressed data and size information recorded on the recording medium 1 are reproduced in the same manner as in the first embodiment, the compressed data is expanded by the expansion means 3, and the compressed expansion area is outputted. The image data (image information) in the non-designated area is stored in the storage unit 4 in order to prohibit the area determination unit 7 from writing the image data in the non-designated area in the storage unit 4 based on the size information. Only the image data of the designated area is stored in the storage unit 4 without being stored in the storage unit 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 of the non-designated area may exist at any of the four corners of the image data of the designated area. If the image data in the designated area has an image size of an integer number of spatial blocks, the image data in the compression / decompression area does not need to include the image data in the non-designated area, and the image data in the designated area is compressed / decompressed. It goes without saying that the image data is. Further, in this case, it goes without saying that the image data write prohibition function in the area determination means 7 does not operate.

Furthermore, the compression / expansion area is not limited to the area of the smallest number of the space blocks including the designated area, but may be any area as long as the area includes the designated area and the area of the integral number of the space blocks. It goes without saying that it is good. In the second embodiment, Y and Pb and Pr sub-sampled in the horizontal direction at a frequency half the sampling frequency of Y have been described.
r may be sampled at any sampling frequency (eg, sampled at the same sampling frequency as Y, eg, subsampled at a quarter of the Y sampling frequency), and so on. It goes without saying that 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 first and second embodiments described above, the storage unit 4 is supplied with the image data of the compression / expansion area, but the area determination unit 7 supplies the image data corresponding to the pixels belonging to the non-designated area (designation Since the writing signal is not generated for the image data of the outer area), the image data of the non-designated area is not stored in the storage means 4, but only the image data of the designated area is stored in the storage means 4. Four
It is needless to say that the configuration in which only the image data of the designated area is supplied is not limited to this, and the following configurations may be included, and such a configuration is included in the present invention.

FIG. 5 is a functional block diagram of the essential parts of the configuration described below. For example, the first gate means 15 is provided at the output destination of the decompression means 3, and the second gate means 16 is provided on the branch line of the pixel corresponding signal supplied from the decompression means 3. When the pixel corresponding signal is supplied from the decompressing unit 3, the area determining unit 7 causes the pixel corresponding to each of the image data in the compressed and decompressed area, which is decompressed and supplied to the first gate unit 15, to belong to the designated area. It is determined whether the pixel belongs to a non-designated area.

When it is determined that the pixel belongs to a non-designated area, the area determining means 7 sends 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. Supply to. When it is determined that the pixel belongs to the designated area, the area determining unit 7 supplies the first gate unit 15 and the second gate unit 16 with a generation signal indicating that the image data corresponding to the pixel is generated.

The first gate means 15 closes the gate when the inhibition signal is supplied and does not pass the image data, and opens the gate only when the generation signal is supplied and passes the image data. Only the image data of the designated area is output from the first gate means 15. The second gate means 16 closes the gate when the inhibition signal is supplied, does not pass the pixel corresponding signal, and opens the gate only when the generation signal is supplied, and allows the pixel corresponding signal to pass.
The second gate means 16 outputs only a pixel corresponding signal indicating a pixel belonging to the designated area.

The area determining means 7 supplies only the write enable signal to the write signal generating means 8 and the pixel detecting signal to the write address generating means 9. The write signal generation means 8 supplies the write signal to the storage means 4 for each pixel (pixel in the designated area) indicated by the pixel corresponding 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 corresponding 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. The function (circuit) blocks of the above-described embodiments may be configured by software or hardware as necessary, and it goes without saying that the present invention includes some aspects. .

Furthermore, the above-mentioned two embodiments are merely examples of the present invention, and various modifications can be made if necessary, and the present invention described in the claims includes all those modifications. It is a thing.

[0044]

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

[Brief description of 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 of a second embodiment of the present invention.

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

[Explanation of symbols]

 1 recording medium 3 expansion means 4 storage means 7 area determination means

Claims (1)

[Claims] 1. In an image processing apparatus for decompressing data in a spatial block unit of M × N (where M and N are natural numbers) pixels, image data of a non-designated area is arbitrarily converted to image data of a designated area of an arbitrary size. A recording medium for compressing image data of a compression / expansion area formed by an integer number of the spatial blocks added with the data in advance in units of the spatial blocks, and recording the generated compressed data; and a recording medium read from the recording medium. Decompressing means for decompressing the compressed data in spatial block units, and determining whether or not the pixels corresponding to each of the image data output in a predetermined order by the decompressing means belong to a designated area or a non-designated area. Area determining means for prohibiting writing of image data corresponding to the pixels belonging to, and the image data of the designated area based on the determination of the area determining means. An image processing apparatus that is configured by arranging storage means for storing only data.