JPH08205080A - Method and device for recording and reproducing image data - Google Patents

Abstract

PURPOSE: To reproduce and display image data sorted in an optional block area selected from image data having a size in excess of a display format at a high speed. CONSTITUTION: A coding means 13 arranges a code dividing image data into blocks of a specific size in the code data to code image data and a file management means 17 is used to record the image data together with coordinates on the image data corresponding to the code position of the codes to a recorder 12 and when optional blocks sorted on the image data are reproduced and required code data are read at a high speed based on management information comprising coordinates and code position stored in the recording device 12, decoded by a decoding means 14 and displayed by a display means 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image data recording / reproducing method and apparatus for reproducing and displaying image data compressed and recorded as coded data.

[0002]

2. Description of the Related Art Generally, an image filing apparatus converts image data into a digital signal, compresses the image data using an image data compression technique such as JPEG system, records the image data in an external recording device, and retrieves arbitrary image data. ， It is intended for playback display.

Further, in the conventional image filing apparatus, the image data size to be filing is the image data of the size of the display format of the apparatus or smaller, for example, 1920 × 1035 image data and the like in the high definition still image filing apparatus. It is common to handle image data of the following sizes.

However, as the image data, horizontally or vertically long image data, or image data that exceeds the display size in both the vertical and horizontal two-dimensional directions, for example, a high-definition display size 6 planes as shown at 21 in FIG. There is image data of 5760 × 2070, which corresponds to the above, and when filing such image data, the following two filing modes are adopted.

As a first method, as shown in FIG. 2, the image data is divided into six on the basis of the display size, and the image data of the six sides are compressed and encoded as independent different files and recorded and retained. Is. In this case, it is necessary for each file to hold each correlation in the original image data as management information in each file.

At this time, when it is attempted to reproduce and display an arbitrary area of the image data that has been blocked, the specified area may extend over a plurality of files, and the code data is read and decoded to obtain the image data. It is necessary to repeat the same operation. Therefore, in addition to the image memory for display, the image memory for storing the decoded image data needs to store the decoded image data in the work image memory in advance and transfer the necessary area to the display image memory. Therefore, a separate work image memory is required, which is a factor of increasing the hardware scale of the image filing device.

The second method is to compress the image data,
There is a form in which it is encoded and recorded and held as a single file. For example, when the image data is compressed and encoded using the JPEG method and is recorded and held as one file, if the display size is adopted as a unit for blocking the image data, the horizontal display value 1920
A special code (restart marker) is arranged for each pixel, and in the vertical direction, it is a scan line unit, actually the scan start,
The encoded image data is managed by using the end code. With this, it is possible to reproduce and display a necessary area in the image data in display size units when decoding the coded data while encoding the image data and managing it in one file.

Further, by making the size of the image data into blocks small, that is, by arranging the restart markers in the horizontal direction closely, the degree of freedom in selection can be improved when reproducing and displaying an arbitrary area of the image data. be able to.

In the case of this method, as compared with the above-described mode in which the file is divided and recorded, the image memory required can be reproduced and displayed only by the image memory for display, and the code data is further stored in one file. Since it can be managed by, the processing for displaying the image is simple, which leads to the reduction of the reproduction time of the image data.

[0010]

In the second method described above, when the code data of the designated arbitrary blocked area is read and the image data is reproduced and displayed, it is necessary for decoding the image data. In order to obtain the coded data, it is necessary to sequentially read the filed coded data from the beginning and scan (scan) the start and end markers and restart markers of each scan.

When this scanning is performed, it is usually processed by software in the control unit including the file management means, so that there is a problem that software overhead is directly reflected in the reproduction time of the image data.

The present invention solves the above-mentioned conventional problems, and eliminates software overhead due to scanning of code data and records image data capable of reproducing and displaying an arbitrary block of image data at high speed. It is intended to provide a reproducing method and an apparatus thereof.

[0013]

In order to solve the above-mentioned problems, an image data recording / reproducing apparatus of the present invention comprises an image input means for inputting image data, an image storing means for holding the image data, and an image data compression means. When generating code data, an encoding unit that arranges a code that divides image data into blocks of a specific size in the code data, a recording device that records the code data, and the generated code data as a file. When recording, the code position in the code file and the corresponding coordinate value on the image data are managed and recorded in the recording device, and when reproducing the image data of any divided block, the code position and the coordinate File management means for reading the corresponding code data from the value from the recording device, decoding means for decoding the code data read from the file management means, and decoding means Display means for displaying after the image data decoded by the image storage means is held, and image data reproduced from the image data recorded as coded data in the recording device by designating a block size for dividing the image data An operation means for selecting, a designation of a block size for dividing the image data from the operation means, and information regarding selection of image data to be reproduced from image data recorded as coded data in the recording device,
For the image input means, control of start and end of input of image data and block size designation for dividing the image data, control of start and end of encoding operation with respect to the encoding means, and recording device with respect to the decoding means It has a configuration including control means for controlling the start and end of the decoding operation of the read code data and a control means for controlling the recording apparatus through the file management means.

[0014]

According to the present invention, in the above structure, for example, when image data having a size larger than the display format is recorded, a code for dividing the image data into blocks of a specific size is arranged in the code data and Image data is encoded, the code position of the code is recorded in the recording device together with the coordinate value on the image data corresponding to the code,
When reading the required code data from the coordinate value and the code position recorded in the recording device, without sequentially scanning the code data in the file,
By obtaining the code position of the required code data in the file from the code position and the coordinate value recorded in advance in the file, the reproduction display of the image data can be performed at high speed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an image data recording / reproducing apparatus according to an embodiment of the present invention, which will be described.

In FIG. 1, 11 is an image input means for inputting image data having a size larger than the display format, 13 is an encoding means for encoding the image data to generate code data, and 14 is an image for decoding the code data. Decoding means for generating data, 12 a recording device for recording coded data, 15 for storing image data input from the image input means 11 and image data read from the recording device 12 and decoded by the decoding means 14. An image memory, 16 is a unit for displaying the image data read from the image memory 15, and 17 is a control for writing and reading the code data generated by the encoding unit 13 or the decoding unit 14 in the recording device 12. A file management means having a function of adding file management information together with code data, and 18 divides image data Selection of the image data to be specified and reproduced lock of size, is an operation unit used to specify the playback area. A control unit 19 controls the recording device 12, the encoding unit 13, the decoding unit 14, the image memory 15, and the operation unit 18 in cooperation with the file management unit 17.

The control unit 19 designates a block size for dividing the image data from the operating means 18, selects image data to be reproduced from the image data recorded as the code data in the recording device 12, and inputs an image. Means 11
For the control of the start and end of the input of the image data and the designation of the image data size, the encoding means 13 controls the start and the end of the encoding of the image data stored in the image memory 15, and the recording means 12 for the decoding means 14. Control of the start and end of the decoding of the code data read from the storage device 12 and control of the recording device 12 through the file management means 17 are performed.

An image data recording procedure and an image data reproducing / displaying procedure in the image data recording / reproducing apparatus configured as described above will be described. In the following description, the image data size is 5760 × 207 as an example of the image data.
The image data 21 having 0 is used as a block size of the image data of 1920 × 1035. Further, the JPEG method will be used as a method for compressing and encoding image data.

First, the image data recording procedure will be described. The image input means 11 is a means for digitizing a film or a video signal, and the image data can be obtained by this means. The input image data is transferred to the image memory 15.

The image data is stored in the image memory 15 and sequentially encoded by the encoding means 13. In the JPEG system, the digitized two-dimensional image data used in this example is divided into an appropriate number of samples, in this embodiment, 8 × 8 (unit is pixel), orthogonal transformation is performed, quantization is performed, and then encoding is performed. . As shown in FIG. 3, when the upper left corner of the image data is the origin coordinate, the horizontal direction is encoded in units of 8 × 8 pixels, and the horizontal direction is 5760 pixels and the vertical direction is 8 pixels (the number of divisions is 720).
Is one scan line. After this, coordinates (X, Y)
When the image data is displayed with, X is the horizontal direction and Y is the vertical direction.

A restart marker can be arranged for each number of pixels specified here (however, the size of the number of samples, 8 pixels are the minimum unit that can be specified). In the case of this example, 192
A restart marker is arranged at 0 pixel (that is, every 240 divisions). FIG. 4 shows an example of code data for one scan line. The data of one scan line starts from the scan start marker 41 in FIG. 4 and ends with the code data body 42 and the scan end marker 44. Further, restart markers 43 are arranged for every designated number of pixels (horizontal direction).
By repeating this in the vertical direction for every sample pixel number (8 pixels) in the vertical direction, a total of 260 scan line encoded data is generated. The points to note here are
Vertically 103 as the block size of image data
Since 5 (pixels) is set, it cannot be divided by 8 pixels, which is the number of sample pixels in the vertical direction, and therefore pseudo data is added for adjustment on the 130th scan line and the 260th scan line. The code is composed of the scan start marker and the restart marker.

Next, the generated code data is recorded and held in the recording device 12 under the control of the file management means 17. Figure 5
Shows the data structure on the file. Reference numeral 51 denotes a file management header required for file management on the control unit 19,
Reference numeral 53 is a JPEG header, and 54 is a code data main body, which is a general file structure of an image filing apparatus adopting the JPEG system.

In the present invention, in addition to the file structure, the scan start marker generated when the image data is encoded and the code position of the restart marker arranged to block the image data (bytes from the beginning of the file) (Represented by a number), and management information 52 including coordinate values on the image data is added.

Here, the management information 52 will be described by taking the lower left block of the image data 21 as an example. This block is composed of code data surrounded by restart markers that appear next from the scan start marker of each of the 131st to 260th scan lines of the code data obtained by encoding the image data. Also, the code data from the scan start marker of the 131st scan line to the restart marker that appears next is coordinates (0, 1035), (191) on the image data.
9,1035), (0,1043), (1919,10)
It corresponds to the partial area represented by 43). The coordinate value in this partial area is (0,1035).

The upper left coordinate value (0, 103) of this partial area
5) and the code position as a pair, the management information 52 of this block is composed of a total of 130 pairs of coordinate values on the image up to the 260th scan line and the code position. This management information 52
Is generated for each block, and in the case of the present embodiment, is composed of a total of 6 blocks of management information 52.

Next, the procedure for reproducing the image data will be described. The control unit 19 reads out the file management header selected from the recording device 12 by the file management unit 17 and the management information 52 of the block in order to reproduce the block area of the image data selected by the operation unit 18, The code position for reading each code data forming the blocked area is obtained.

Next, the file management means 17 seeks the code data required from the code position from the head of the code data at high speed from the recording device 12 and reads it out and transfers it to the decoding device 14. The image data decoded by the decoding device 14 is stored in the image memory 15 and displayed on the display means 16.

As described above, according to the present embodiment, when the image data having a size larger than the display format is encoded, the code position of the scan start code or the restart marker code arranged in the code data is set. , By managing the coordinate values on the image data to which the respective codes face each other in the file, the code data necessary for playback display can be obtained.
It is possible to directly seek and read from the beginning of the file without sequentially scanning, and it is possible to reproduce and display the image data at high speed.

[0030]

As described above, according to the present invention, when image data is encoded and recorded as a file, the code position in the file of the code arranged for blocking the image data corresponds to the image data. By managing the coordinate values together and additionally recording them in a file and recording them in the recording device, it is possible to reproduce and display the selected arbitrary blocked image data at high speed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an image data recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a structural diagram of image data

FIG. 3 is an explanatory diagram of a procedure for encoding image data.

FIG. 4 is an explanatory diagram of code data.

[Figure 5] File structure diagram

[Explanation of symbols]

 11 Image Input Means 12 Recording Device 13 Encoding Means 14 Decoding Means 15 Image Memory 16 Display Means 17 File Management Means 18 Operating Means 19 Controller 21 Image Data 41 Scan Start Markers 42 Code Data Main Body 43 Restart Markers 44 Scan End Markers 51 File Management Header 52 Management Information 53 JPEG Header 54 Code Data Main Body

Claims (2)

[Claims] 1. When recording image data, a code for dividing the image data into blocks of a specific size is arranged in the code data to encode the image data, and the code position of the code is set to the When the image data is recorded in the recording device together with the coordinate value on the image data corresponding to the code and the image data is reproduced, the necessary code data is read from the coordinate value and the code position recorded in the recording device. However, an image data recording / reproducing method characterized by decoding. 2. An image input means for inputting image data,
An image storage unit for holding the image data; and an encoding unit for arranging a code for dividing the image data into blocks of a specific size in the code data when the image data is compressed to generate the code data. A recording device that records the code data, and when recording the generated code data as a file, manages the code position in the file along with the corresponding coordinate value on the image data, and stores the code data in the recording device. When reproducing image data of an arbitrary block that has been recorded and divided, a file management unit that reads corresponding code data from the code position and the coordinate value from the recording device, and read from the file management unit. Decoding means for decoding the coded data, and image data decoded by the decoding means is displayed after being held in the image storage means. Display means to perform, operation means for designating a block size for dividing the image data and selecting image data to be reproduced from the image data recorded as the code data in the recording device, and the operating means Information regarding selection of a block size for dividing the image data and selection of image data to be reproduced from the image data recorded as the code data in the recording device is received, and the image input unit inputs the image data. Control of the block size designation for dividing the start and end of the image data, the start and end of the encoding operation with respect to the encoding means, and with respect to the decoding means of the code data read from the recording device. Control of the start and end of the decryption operation, and the recording device through the file management means. Image data recording and reproducing apparatus, characterized in that a control means for controlling the.