JPH07302468A - Moving image and voice recording and reproducing device - Google Patents

Abstract

PURPOSE:To make an editting work efficient and easy by enabling reproducing continuously videos recorded in separated areas on a medium. CONSTITUTION:A video signal inputted to an A/D conversion part 1 is converted into digital data to be recorded in a recording part 2. Data read out from the recording part 2 are temporarily stored in a buffer part 3 and then outputted to a D/A conversion part 4 to be converted into a video signal. Then, at the time of reproducing data being discontinuous on the medium, data can be continuously reproduced without being timewisely interrupted by making a data reading speed faster than the speed required for a reproducing and by storing data in the buffer while performing the look-ahead of data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving image and audio recording / reproducing apparatus, and more particularly, to a video recording / reproducing apparatus for recording / reproducing a video signal on a randomly accessible medium, which has a data read speed. A video and audio recording / reproducing apparatus capable of continuously reproducing data recorded in a distant area on the medium by providing a buffer for storing the read data at a speed higher than that required for reproduction. Regarding

[0002]

2. Description of the Related Art Conventional VTR (Video Tape Recorder)
When performing editing on a tape medium such as, for example, it is necessary to repeat fast forward / rewind in order to search for a desired editing position. Further, the editing work is time-consuming because it is necessary to copy the original image tape to the editing tape. When recording video / audio data on a hard disk or magneto-optical disk, the random access function can be used to streamline the search, but if the playback data is not stored in a continuous area, Since it cannot be reproduced, the original work must still be copied to a new area.

A known document describing a conventional information recording / reproducing apparatus is, for example, Japanese Patent Laid-Open No. 5-36250. In this publication, in order to shorten the time for reading out a moving image such as video information using an optical disc, the address information of the information track and the address information of the image expressed in the form of a time code are mutually converted. As a result, data is input based on the address information of the image, and access to the optical information recording medium is performed based on the address information of the information track.

[0004]

As described above, in the conventional information recording / reproducing apparatus, when the temporally continuous data are recorded at positions distant from each other on the disc, the read head is moved to the next position. The data will be interrupted during the move to. Therefore, during that time, the screen cannot be updated, and the image stops or cannot be seen. Therefore, there is a problem that the data that should be continuously reproduced is reproduced intermittently. For example, in the above-mentioned Japanese Patent Application Laid-Open No. 5-36250, "a method for reading a moving image by an optical disc and an optical information recording / reproducing apparatus", the time code of the image and the track address of the optical disc are mutually converted to enable random access or high-speed search. However, when continuous moving images are recorded on discontinuous tracks, they cannot be continuously reproduced.

In addition, when editing is performed with such a device, a new area is created in order to extract necessary parts from the original series of image / audio data and reproduce them in a desired order. Must be copied continuously so that the edited data is recorded in a continuous area, the continuous reproduction is impossible. Therefore, it takes time to copy and a new disk area is required. To avoid this problem, it is possible to manage only the address of the data on the disk and manage the head address of the area connected by editing as a table, but with this, the read head of the disk manages the next area. Data cannot be read while moving to search,
There was a drawback that playback would be interrupted.

The present invention has been made in view of the above circumstances, and is a video recording / reproducing apparatus for recording / reproducing a video signal on / from a randomly accessible medium. An object of the present invention is to provide a moving image and audio recording / reproducing apparatus capable of continuously reproducing data recorded in a distant area on a medium by providing a buffer which is faster than the speed and stores read data. I am trying.

[0007]

In order to solve the above-mentioned problems, the present invention provides (1) conversion means for converting a moving image, a sound and a synchronization signal into digital data, and data converted by the conversion means. A video recording / reproducing apparatus comprising a recording means for recording on a randomly accessible medium and a reproducing means for reading data recorded by the recording means and reproducing a moving image / sound / synchronization signal. By reading the data from the device faster than the speed required for playback, and prefetching the data and storing it in the buffer, when playing discontinuous data on the medium, there is no interruption in time and continuous Being able to play, and (2)
Controlling recorded data using management data recorded in a special area provided in the medium, and further,
(3) In the above (2), a function for compressing / decompressing digital data obtained by converting a moving image / sound is provided, and position information of an intra-coded frame is used as management data. It is characterized by that.

[0008]

According to the present invention, the converting means for converting the moving image, the sound and the synchronizing signal into digital data, the recording means for recording the data converted by the converting means in a randomly accessible medium, and the recording means. Since there is a reproducing means for reproducing the moving image / sound / synchronous signal by reading the data recorded by, there is a discontinuous area on the disc during the reproduction of the video, and the search is performed to the next area. while,
Even when data cannot be read from the disk, the data read up to that point and stored in the buffer is played back, so that data can be played back without interruption during the search time.

[0009]

Embodiments will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining an embodiment of a moving image and audio recording / reproducing apparatus according to the present invention. In the figure, 1 is an A / D conversion unit for converting input data into a digital signal, 2
Is a recording unit for recording data, 3 is a buffer unit (buffer memory) for storing data read from a medium, 4 is a D / A conversion unit for converting data into analog, and 5 is a control unit for performing overall control. The video signal input to the A / D conversion unit 1 is converted into digital data here and recorded in the recording unit 2. The data read from the recording unit 2 is temporarily stored in the buffer unit 3 and output to the D / A conversion unit 4 to be converted into a video signal.

In this embodiment, for example, as shown in FIG. 2, in the case where temporally continuous data is written continuously from the area A to the area B, the data written in the area A is After reading, a seek operation of moving the read head to the area B is required. At this time, the data read speed can be doubled by doubling the rotation speed of the disk, for example. The read data is reproduced via the buffer memory 3. By doing this, while the data exists in the buffer memory 3,
It becomes possible to access the following areas.

Further, when recording on a disc, information indicating how one temporally continuous video data is arranged and recorded on the disc is also recorded. For this information, an area for management data is provided in an area different from the area of the data on the medium, and the position information of each area is recorded therein as shown in FIG. This management data area should be placed at the outermost or innermost position depending on whether the standby position of the read head is the outermost or innermost position of the medium so that it can be read easily when the medium is mounted on the recording / reproducing apparatus. desirable.

Two types of management data are prepared and used. One is for management of a data area used for recording, and the other is for management of an unused area which is not yet used for recording. By reading and storing this in advance by the control unit 5, the area can be prefetched. The position information stored in this area may be a logical address attached to the entire disk or a physical address physically indicating the position.

Editing using these methods will be described below. 4A and 4B are views showing management data. In the state where no data is recorded at all, the management data in the recorded area is empty, and all the data areas are registered in the unused area management data as shown in FIG. 4B. When recording, an area address is taken out from the head of the unused area management data and the data is recorded in the area on the medium indicated by the address. Then, the address is registered in the recorded area management data. Registering means adding new data after the area pointed to by the tail pointer of the recorded area management data, and updating the data pointed by the tail pointer to the one just added. Further, the data of the used area is deleted from the unused area management data. Deletion means updating the data pointed to by the first pointer to point to the next data. Also, editing using this can be performed as follows.

(1) When inserting data at an arbitrary position FIGS. 5A and 5B are diagrams showing a case where data is inserted at an arbitrary position. In this case, first, data in a required area is extracted from the unused data area. This is to take in order from the data pointed to by the head pointer of the unused area management data, and change the head of the remaining data so that the head pointer points. Write data to the address of the area on the media obtained from this,
Further, the data of this recorded area is added to the recorded area management data. This addition looks like this: First, as shown in FIG. 5A, the pointer indicating the position to be inserted in the recorded area management data is changed to point to the beginning of the area just recorded. Next, as shown in FIG. 5B, the last pointer of the connection of the management data indicating the area just recorded is changed to point to the management data located at the inserted position.

(2) When deleting data from an arbitrary position FIGS. 6A to 6D are diagrams showing a case where data is deleted from an arbitrary position. In this case, first,
As shown in FIG. 6A, the pointer pointing to the beginning of the area to be deleted is changed to point to the first data next to the area to be deleted, as shown in FIG. 6B. The data indicating the deleted area is added to the end of the unused area management data, as shown in FIGS. 6 (c) and 6 (d). As a result, the unnecessary area can be used again for recording. By these operations, the basic work of editing can be performed, and repeated insertion / deletion can be performed.

When such editing work is repeated, a series of video data is arranged in a discontinuous area on the medium. However, by rotating the disc at a high speed, the reading speed is increased and the buffer is temporarily stored. By storing, it is possible to search and read the distant area during the time for reproducing the data stored in the buffer. As a result, the data recorded in the distant area on the disc can be continuously reproduced.

FIG. 7 is a diagram showing another embodiment of the moving picture and audio recording / reproducing apparatus according to the present invention. In the figure, 11 is a compression section, 12 is an expansion section, and other operations are the same as in FIG. The parts are given the same reference numerals. A compression unit 11 and an expansion unit 12 are added to the configuration of the embodiment shown in FIG. The data flow is the same operation as the embodiment shown in FIG. 1, except that the data is compressed before recording and decompressed before D / A conversion.

MPEG, which is an international standard for moving picture compression
In the (Moving Picture Expert Group) method, it is divided into three types of frames depending on the frame used for compression. The first is to perform compression using only the data of the frame currently being compressed.
Call it a picture. The second is to compress using the data of the past frame and the data of the current frame.
-It is called a picture. The third is a B-picture that is compressed using data of past and future frames and data of the current frame.

FIG. 8 shows I-pictures, P-pictures and B-pictures.
-Figure showing a picture. In the figure, I1 is an I-picture, B2, B3, B5, B6 are B-pictures, P4, P
7, ... PX is a P-picture. Similarly, when decompressing, the data of another frame is referred to. These frames are arranged in order such as IBBPBB.
If you number these and call them I1B2B3P4B5B6 ..., P4 will use I1 to perform compression / expansion, and B2B
3 performs compression / expansion using I1 and P4. The next appearing P uses P4. From one I-picture to the next I-
The GOP (Group of
Picture). In this GOP unit, since P and B refer to the frames before and after, it cannot be cut in the middle, so it is GOP to cut for editing etc.
It will be done in units.

By making the area information on the disk indicated by the management data in the embodiment shown in FIG. 1 point to the head of this GOP, that is, the area in which the I-picture is recorded, compression / expansion by the MPEG system is performed. Editing can be performed in a recording / reproducing apparatus that performs. Moreover, the efficiency of the editing work can be improved by the method shown in the embodiment shown in FIG.

[0021]

As is apparent from the above description, according to the present invention, data is read from the medium faster than the data rate required for reproduction, and is temporarily stored in the buffer for reproduction, so that the medium is separated from the medium. The data recorded in the discontinuous area can be continuously reproduced without interruption. As a result, the editing work can be performed only by controlling the management data of the area without copying the data on the medium. Therefore, it is not necessary to use a new medium area for editing, and the editing work can be instantaneously performed only by controlling the management data.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a moving image and audio recording / reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing that data is recorded separately on a time-sequential data disk according to the present invention.

FIG. 3 is a diagram showing that management data according to the present invention manages a distant area on a disc.

FIG. 4 is a diagram showing configurations of unused area management data and recorded area management data in the present invention.

FIG. 5 is a diagram showing insertion of area management data in the present invention.

FIG. 6 is a diagram showing deletion of area management data in the present invention.

FIG. 7 is a diagram showing another embodiment of a moving image and audio recording / reproducing apparatus according to the present invention.

FIG. 8 is a diagram showing three types of frames used for compression in the present invention.

[Explanation of symbols]

1 ... A / D conversion unit, 2 ... recording unit, 3 ... buffer unit (buffer memory), 4 ... D / A conversion unit, 5 ... control unit.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location H04N 5/937 (72) Inventor Yoichi Fujiwara 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Shares In-house (72) Inventor Hiroyuki Katata 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture

Claims (3)

[Claims] 1. A conversion means for converting a moving image, a sound and a synchronization signal into digital data, a recording means for recording the data converted by the conversion means on a randomly accessible medium, and a recording means for recording the data. A video recording / reproducing apparatus comprising a reproducing means for reading data and reproducing a moving image / sound / synchronous signal, wherein a data reading speed from a recording medium is made faster than a speed necessary for reproducing and the data is pre-read. Then, the moving picture and audio recording / reproducing apparatus is characterized in that when the discontinuous data is reproduced on the medium, the data can be continuously reproduced without interruption in time by storing the data in a buffer. 2. The moving image and audio recording / reproducing apparatus according to claim 1, wherein the recorded data is controlled by using management data recorded in a special area provided in the medium. 3. A function for compressing / decompressing digital data obtained by converting a moving image / sound, and using position information of an intra-coded frame as management data. The moving image and audio recording / reproducing apparatus according to claim 2.