JPH07226902A - Picture data recording medium and recording and reproducing device - Google Patents

Abstract

PURPOSE:To easily attain random access of an image without need of lots of memories. CONSTITUTION:Heads of a 1st frame of a still picture 104 or a moving picture are arranged at an equal interval, and the head of the 1st frame of the still picture 104 or the moving picture is arranged just after a header including a sector address 103, and when the still picture 104 is finished on the way of a sector, dummy data 105 are filled up to the end of the sector and a sector address 101 representing a position of the head of a 1st frame of the first moving picture is stored in a specific disk management area to implement random access of a picture with less memory quantity.

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 medium of a storage medium system (disk, tape, etc.) and a recording / reproducing apparatus for recording / reproducing image information.

[0002]

2. Description of the Related Art In recent years, multimedia devices for mixing and digitizing still images, moving images, voices, characters, etc. and recording or reproducing them on tapes, disks, etc. have begun to spread.

A conventional image data recording / reproducing apparatus will be described below by taking a disk as an example.

FIG. 3 shows a structure of a reproducing apparatus for reproducing arbitrary images by accessing arbitrary image data according to a designated image number. First, the image number is given by a manual input operation or application software, and decoded by the address decoder 301 into a sector address on the disk. According to the decoded address, the read sector control unit 302 relatively calculates the current position and the position of the address to be accessed and repeats until the designated address is reached. If you can access the specified address, read the data and read the signal 30
4, the header of the image data is detected and the image data is taken out. The extracted image data is subjected to decoding processing of compressed data or decoding processing such as interpolation processing by the image decoding means 305. The decoded data is output as image data.

Next, the address decoder 30 shown in FIG.
1 will be described in detail. FIG. 4 shows a format for managing image data by the conventional table management method. A table of sector addresses of each image on the recording medium is stored in a management area for managing data on the recording medium, and this table is loaded into the memory of the image reproducing apparatus when the disc is started. Further, the recording medium is divided into areas of a predetermined size in advance, which are generally called sectors. At the beginning of each divided sector, a synchronization signal and a portion called a header in which the attribute information of the sector is stored are formed. Image data and various data (voice, characters, etc.)
, The image data starts in the middle of the sector or ends in the middle of the sector, as shown in FIG.

Next, an image access method based on the table management method will be described. First, when the apparatus is activated, the information in the management area on the medium in FIG. 4 is read and stored in, for example, the memory on the microcomputer. At that time, the sector address table representing the position information of the image is also stored in the memory at the same time. Now, when the image number is manually input or given by the application software, the desired address is accessed by referring to the sector address table expanded on the memory as shown in FIG. You can read the data.

[0007]

However, in the above-mentioned conventional configuration, the sector address table of each image must be stored in the memory when the disk is started, and a large amount of memory is required. For example, if the sector address is 2
If the image number is represented by 4 bits and the image number is from 0 to 99, a total of 2400 bits of memory is required.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to easily enable random access to an image without requiring a large amount of memory.

[0009]

In order to achieve this object, a recording medium and a recording / reproducing apparatus of the present invention provide still images or moving image sequences with heads arranged at equal intervals, and still images or , The beginning of the moving image sequence is a sector synchronization signal,
It is placed immediately after the header, and when the image data ends in the middle of a sector, it is filled with dummy data until the end of the sector, and the still image data of the first frame or the first frame of the first moving image sequence By storing the information indicating the position of the head in a specific management area, it is possible to randomly access an image with a small memory amount.

[0010]

According to the present invention, with the above configuration, it is possible to perform random access to an image with a small memory amount.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings when a disk is used as a recording medium.

FIG. 3 shows a structure of a reproducing apparatus for reproducing arbitrary images by accessing arbitrary image data according to a designated image number. First, the image number is given by a manual input operation or application software, and decoded by the address decoder 301 into a sector address on the disk. According to the decoded address, the read sector control unit 302 relatively calculates the current position and the position of the address to be accessed and repeats until the designated address is reached. If you can access the specified address, read the data and read the signal 30
4, the header of the image data is detected and the image data is taken out. The extracted image data is subjected to decoding processing of compressed data or decoding processing such as interpolation processing by the image decoding means 305. The decoded data is output as image data.

Next, the address decoder 30 shown in FIG.
1 will be described in detail. FIG. 1 shows a format configuration of an image data recording medium in an embodiment of the present invention. In FIG. 1, the first frame of the still image or the first frame of the first moving image sequence among the images on the recording medium is included in the management area for managing the data on the recording medium. The sector address is stored,
Each image is accessed based on this address. Further, the recording medium is divided into areas of a predetermined size. They are generally called sectors. At the beginning of each divided sector, a synchronization signal and a portion called a header in which the attribute information of the sector is stored are formed. When storing image data and various data (sound, characters, etc.), as shown in FIG. 1, the beginnings of the image data are arranged at equal intervals, and the beginning of the image is immediately after the sector synchronization signal and the header. When the image data ends in the middle of a sector, the still image data or the moving image sequence extends over a plurality of sectors, and the dummy data is filled up to the end of the finished sector.

Next, an image access method based on the arithmetic method will be described. First, when the device is started,
The information in the management area on the medium is read and stored in, for example, the memory on the microcomputer. At that time, the sector address indicating the position information of the first frame of the still image or the first frame of the first moving image sequence is also stored in the memory at the same time. Now, when the image number is manually input or given by application software, as shown in FIG. 2, the image number and each frame of a predetermined still image or the first image of each moving image sequence Is multiplied by the interval of the sector unit of the frame by the multiplier 201, and the result is multiplied by the sector address of the first frame of the still image stored in the memory or the first frame of the first moving image sequence. A desired sector address is calculated by adding by the adder 202. Then, by the calculated sector address, it is possible to access the target disk and read the image data.

[0015]

As described above, according to the present invention, the heads of images are arranged at equal intervals, and the head of a still image or the head of each moving image sequence is placed immediately after a sector synchronization signal and a header. And when the image data ends in the middle of the sector,
By filling up to the end of the finished sector with dummy data and storing still image data of the first frame or information indicating the position of the beginning of the first frame of the first moving image sequence in a specific management area , Random access of images can be performed with a small memory amount.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining a format of a recording medium in an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an address decoder which obtains a sector address of an image to be accessed from an image number in the embodiment.

FIG. 3 is a block diagram showing a configuration of an image data reproducing device for designating an image number and reading image data on a disc in a conventional example.

FIG. 4 is an explanatory diagram for explaining a format of a recording medium in a conventional example.

FIG. 5 is a block diagram showing a configuration of an address decoder for obtaining a sector address of an image to be accessed from an image number in a conventional example.

[Explanation of symbols]

 101 Sector address of the first image 102 Synchronous signal 103 Sector address 104 Image data 105 Dummy data

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location H04N 5/93 (72) Inventor Tatsuya Murata 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Wataru Masuno 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A recording medium having a header storing a sync signal and its address, wherein the heads of still image data and moving picture data start from the head of a data area after the sync signal and the header. Image data recording medium. 2. In a packet including a sync signal, a header and a data area, when still image data and moving image data end in the middle of the packet, pad up to the end of the data area of the completed packet with dummy data. The image data recording medium according to claim 1, wherein 3. A plurality of still images or a moving image sequence,
A frame of a still image or a first frame of a moving image is continuously arranged at a certain place so that the heads of the first frame are arranged at equal intervals, and the first frame of the still image, or
An image data recording medium characterized in that information indicating the position of the beginning of the first frame of the first moving image sequence is stored in a specific management area. 4. A recording / reproducing apparatus for recording or reproducing the image data recording medium according to claim 1 or 3.