JPH09214881A - Video data recording method, video data recorder and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend recording time by conducting deframing recording for each certain frame interval. SOLUTION: When a moving image recording stop key is not depressed after video data are stored to the capacity of a hard disk, a system control section switches a moving image recording mode to a 1/2 de-framing recording mode and overwrites frame data deframed by 1/2 at an interval of one frame onto full frame data 1, 2, 3,...X-1 recorded before. Furthermore, when th stop key is not yet depressed even after the recording above, frame data with 1/4 de-framing are overwritten onto the frame data 1, 3, 5,...X-5, X-3, X-1,...Y-4, Y-2, Y with 1/2 de-framing and recorded before at an interval of 3 frames. Furthermore, when th stop key is not yet depressed even after the recording above, the operation mode is switched into the 1/8 de-framing recording mode and the recording is continued similarly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for recording compression-encoded video data or the like on a recording medium such as a magnetic disk, and more particularly to a technique for extending the recording time by dropping frames. .

[0002]

2. Description of the Related Art Hard disk devices are widely used as auxiliary storage devices for computers. A hard disk, which is a medium used in a hard disk device, is formed by stacking a plurality of magnetic disks each having a flat substrate coated with a magnetic material according to the capacity and rotating the disk at several thousand rpm.

Concentric recording tracks are set on the recording surface of the magnetic disk. And in each recording track,
Data is recorded in a unit called a sector (normally 512 bytes) in which a track is divided into sectors. A sector address is provided in each sector, and the data recording / reproducing position can be designated by designating this sector address.

The zone bit recording method is adopted in the hard disk. As shown in FIG. 8, in zone bit recording, the surface of a magnetic disk is concentrically divided into a plurality of zones, and the outer zone has a high sector density and the inner zone has a high sector density. By lowering the signal transfer speed for each zone stepwise and averaging the recording density on the surface, the density is increased. Such a method is a conventional C
AV (Constant Angler Veloc
ZCAV (Zoned Const)
It is called the ant Angular Velocity) method.

In a hard disk, such Z
Since the CAV method is adopted, the read / write transfer rate in the outer zone is high, and the read / write transfer rate gradually decreases toward the inner zone. Therefore, the read / write transfer rate in the innermost zone is the lowest.

Further, the sector address of a sector, which is a unit for exchanging data with an external system, is assigned from the outer zone to the inner zone. The start sector address is the outermost zone and the end sector address is the outermost zone. It exists in the inner zone.

[0007]

With the increase in capacity and cost of hard disks and the development of data compression technology, video data has been compressed and recorded and reproduced on the hard disk.

Conventionally, since a hard disk has been used as a data storage medium for computer use, no matter how the sector address is arranged on the hard disk and how the data is arranged, the external host system even knows the position. It is important to be able to read and write data accurately and accurately.
No attention has been paid to the write transfer rate or to which data is located at which sector address.

Therefore, when recording continuous data such as video data, the continuous data is divided on the actual magnetic disk due to the file system of the operating system of the microcomputer that manages the hard disk drive. It was often recorded.

However, if such continuous data is divided and recorded, a seek for moving the magnetic head onto a target track and a waiting for rotation until the target sector come directly under the magnetic head are made. It happens frequently while recording and reproducing data. Therefore, there is a problem in that the average data transfer rate is lowered and the recording and reproducing of data on the external host system side cannot be performed in time.

Further, since the video data can be recorded only by the capacity of the magnetic disk, it is necessary to set the recording time in advance according to the capacity of the magnetic disk.
Therefore, when the video data of which the duration is unknown is recorded in advance, there is a problem that the capacity that can be actually recorded is exceeded on the way and the video data of the portion to be recorded cannot be recorded.

The present invention has been made in view of the above problems, and provides a video data recording method, a video data recording apparatus, and a recording medium capable of extending the recording time.

[0013]

In order to solve the above-mentioned problems, a video data recording method according to the present invention has a capacity of a predetermined recording area of a recording medium when recording the video data on the recording medium. All the frames of the video data are recorded until the recording is finished, and then the frame skip recording is performed.

Here, the frame does not mean a frame for a field of interlaced video data such as an NTSC video signal.
It means one image. Therefore, recording all either one of the odd field and the even field of the NTSC video signal is also a full-frame recording of the video data.

Further, the video data recording apparatus according to the present invention comprises a first means for recording the video data on the recording medium and a second means for managing the video data recorded by the first means. The second means is characterized in that all the frames of the video data are recorded until the recording of the capacity of the predetermined recording area of the recording medium is completed, and then the frame-down recording is performed. .

Here, the recording device is a device having at least a recording function. Therefore, it has a recording and reproducing function,
A so-called recording / reproducing device is included.

According to the present invention, when the video data to be recorded does not exceed the capacity of a predetermined area on the recording medium, it is recorded as a full frame, and when it exceeds the capacity, it is previously recorded by frame skipping. The frame data is updated with frame data of a new image at a certain frame interval.

This makes it possible to record video data longer than the time actually recorded in a full frame when the recording time of the video data is unknown or when it is desired to extend the recording time midway. As a result, the video to be recorded is not interrupted halfway due to the recording capacity limit of the recording medium, and all the video data to be recorded can be recorded.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [1] Configuration of a hard disk recording / reproducing device to which the present invention is applied [2] Operation of a hard disk recording / reproducing device to which the present invention is applied (1) 1) Recording of video data (2) Reproduction of video data [3] Configuration of removable disk recording / reproducing apparatus to which the present invention is applied [4] Operation of removable disk recording / reproducing apparatus to which the present invention is applied (1) System initialization (2) Recording of video data (3) Reproduction of video data will be described in detail.

[1] Configuration of Hard Disk Recording / Reproducing Apparatus to which the Present Invention is Applied FIG. 1 is a block diagram showing the configuration of a hard disk recording / reproducing apparatus to which the present invention is applied.

As shown in this figure, this hard disk recording / reproducing apparatus has a hard disk drive 1, a compression encoder 2 for compressing and coding frame data of an image input to the hard disk drive 1, and an image output from the hard disk drive 1. A decoding decoder 3 for decompressing and decoding the frame data of, and an image memory 4 for temporarily storing the frame data of the image input to the compression encoder 2 or the frame data of the image output from the decoding decoder 3. An A / D conversion circuit 5 that digitizes an input image and sends it to the image memory 4 and a D / A conversion circuit 6 that obtains an output image by analogizing the image read from the image memory 4 are provided.

Further, the hard disk recording / reproducing apparatus comprises a user interface key 7 and a system controller 8 for controlling the entire apparatus according to the input information of the user interface key 7. The user interface key 7 is provided with a moving image reproduction key 71, a moving image recording start key 72, and a moving image recording stop key 73.

The hard disk drive 1 comprises a hard disk interface 11, a hard disk internal control device 12, a magnetic head 13 and a magnetic disk 14. Then, by issuing a sector address and a read / write command from the external system side through the hard disk interface 11, data recording / reproduction is performed.

[2] Recording / reproducing operation of hard disk recording / reproducing apparatus to which the present invention is applied (1) Recording of video data FIG. 2 shows a recording pattern when the video data to be recorded does not exceed the capacity of the hard disk (full frame recording). Show. Then, (1) of FIG. 3 shows a pattern when the video data to be recorded exceeds the capacity of the hard disk once (1/2 frame-drop recording), and (2) of FIG. 3 shows a pattern when it exceeds twice (1/4). The pattern of time-lapse recording) is shown. In addition,
The arrow in the recording direction in FIG. 3 indicates the order of frames of video data after recording.

When the moving picture recording start key 72 of the user interface key 7 is pressed, the system controller 8 causes the A / D
The conversion circuit 5 and the image memory 4 are controlled to temporarily store the video data of the input image digitized by the A / D conversion circuit 5 in the image memory 4. Here, the input image is, for example, an NTSC video signal.

Next, the video data read from the image memory 4 is compression-encoded by the compression encoder 2 and passed to the hard disk interface 11. Here, before passing the compression-encoded video data to the hard disk interface 11, the system control device 8 beforehand
The hard disk internal control device 12 in the hard disk drive 1 is instructed to move the magnetic head 13 to the track at the start address of the magnetic disk to make the video data recordable.

As described above, the compression-encoded video data input from the hard disk interface 11 is recorded on the magnetic disk 14. When the video data does not exceed the hard disk capacity, the video data is continuously recorded in full frames as shown in FIG. As shown in FIG. 2, video data for one frame is recorded at consecutive sector addresses on the hard disk.

When the moving image recording stop key 73 of the user interface key 7 is pressed, the system controller 8
A stop command is sent to the A / D conversion circuit 5, the image memory 4, the compression encoder 2, and the hard disk drive 1,
Stop movie recording.

If the moving picture recording stop key 73 is not pressed even if the video data of the hard disk capacity has been recorded, the system control unit 8 switches the moving picture recording mode to the half frame dropping recording mode, Figure 1 (1)
As shown in, the previously recorded full-frame data 1, 2, 3, ..., X-2, X-1, X are overwritten with frame data dropped every other frame by 1/2 frame. To go. Here we recorded previously 2, 4, 6,
..., X + 1, X + 3, X on X-4, X-2, X
+5, ..., Y-4, Y-2, and Y frame data are recorded. Here, whether or not the hard disk capacity has been recorded is identified by monitoring the write sector address.

Further, if the moving picture recording stop key 73 is not pressed even after the half-frame dropping recording is completed and the recording is finished, the system controller 8 sets the moving picture recording mode to 1/4 this time. The frame data is switched to the frame drop recording mode, and as shown in (2) of FIG. 3, the frame data 1, 3, 5, ...
5, X-3, X-1, X + 1, X + 3, X + 5, ...
・, Y-4, Y-2, Y is 1 / third every 3 frames
Overwrite the frame data with 4 frames dropped.
Here, the previously recorded X + 3, X + 7, X + 11,
..., Y-8, Y-4, Y on top of Y + 2, Y + 6, Y
Frame data of +10, ..., Z-8, Z-4, Z are recorded.

If the moving image recording stop key 73 is not pressed even after the recording has been completed after the 1/4 frame dropping recording, the system controller 8 sets the moving image recording mode to 1 /
Switching to the 8-frame drop recording mode and continuing recording in the same manner. However, in the case of moving image data, the movement of the image becomes unsmooth when the interval between the frames to be recorded becomes long. Therefore, the recording may be stopped when the frame interval becomes longer to some extent.

By thus increasing the frame dropping interval, the recording time of the video data can be extended without increasing the capacity of the hard disk. Also, by recording one frame of video data in consecutive sector addresses of the hard disk, the average data transfer rate can be improved.

(2) Playback operation of video data FIG. 4 shows a playback pattern (full frame playback) in the case where the recorded video data does not exceed the hard disk capacity (full frame recording shown in FIG. 2). And FIG.
Indicates that the recorded video data exceeds the capacity of the hard disk once (1 / 2-frame drop recording shown in (1) of FIG. 3)
6 shows a reproduction pattern in the case of (1 frame skipping reproduction), and FIG. 6 shows reproduction when the recorded video data exceeds the hard disk capacity twice (1/4 frame skip recording shown in (2) of FIG. 3). A pattern (1/4 frame drop reproduction) is shown.

When the moving image reproduction key 73 of the user interface key 7 is pressed, the system controller 8 determines whether the recorded image data is recorded in full frame or in frame skipping. In order to reproduce, the hard disk internal control device 12 of the hard disk drive 1 is notified of the reproduction start address of the desired video data via the hard disk interface 11.

The hard disk internal control device 12 reproduces the video data compressed and encoded from a desired sector address and passes the data to the decoding decoder 3 via the hard disk interface 11. The decoding decoder 3 decodes and expands the compression-coded video data at a timing that follows it according to whether it was recorded in a full frame or in a frame skipping mode, and temporarily stores it in the image memory 4. The decoded and decompressed video data stored in the image memory 4 is D / A converted via the D / A conversion circuit 6 and becomes an output image.

The above operation is continued until the reproduction of the video data of the time recorded on the hard disk is completed. That is, in the case of the full frame reproduction shown in FIG. 4, the frames 1, 2, 3, ... X-2, X-1, X are reproduced in this order. In this case, the reproduction is completed in one round of the magnetic disk.
Further, in the case of the 1/2 frame skipping reproduction shown in FIG.
Frames 1, 3, 5, ..., X-3, X-1 are reproduced on the second lap, and X + 1, X + 3, X + 5, ..., Y are reproduced on the second lap.
-4, Y-2, Y are reproduced. Further, 1 / shown in FIG.
In the case of 4-frame drop playback, frame 1,
5, 9, ..., X-7, X-3 are reproduced, and X is reproduced on the second lap.
+1, X + 5, ..., Y-6, Y-2 are reproduced, and Y + 2, Y + 6 ,.

As described above, by playing back the frame-recorded video data by frame-by-frame reproduction, the recorded video data can be viewed quickly. If each frame of the video data recorded with frame skipping is reproduced a plurality of times according to the frame skipping interval, it can be reproduced at the time interval of the input video data.

In the above description, the entire capacity of the hard disk is recorded, but it is also possible to record on a continuous part of the total capacity of the hard disk.

[3] Structure of Removable Disk Recording / Reproducing Apparatus to which the Present Invention is Applied FIG. 7 is a block diagram showing the structure of a removable disk recording / reproducing apparatus to which the present invention is applied. Here, the removable disk drive 1'and the control device work memory 9
Since the other parts are the same as those in FIG. 5, the same numbers are given. The description of the configuration of the above parts is omitted. As for the removable disk drive 1 ', the same numbers and "'" are attached to the portions corresponding to the hard disk drive 1 in FIG.

The removable disk drive 1'includes a removable disk interface 11 ', a removable disk internal controller 12', and a removable disk reader 13 '. Then, the removable disk 14 'is inserted into the removable disk drive 1'and used.

The removable disk 14 'is provided with a removable disk information recording area 15 for zoning information of the removable disk (total capacity, total number of sectors, start sector address and end sector address,
It holds the capacity per sector, etc.).

Although the removable disk information recording area 15 is arranged at the outermost circumference in the figure, it may be at the innermost circumference. Further, it may be an area in which only reproduction of the disc is possible or an area in which recording and reproduction are possible. Further, it may be stored in a semiconductor memory (RAM or ROM) provided separately from the disk. Further, a hole or the like may be provided in the housing of the removable disk 14 'so that the system control device 8 can identify it.

When the removable disk 14 'is inserted into the removable disk drive 1', the removable disk information is passed to the system controller 8 via the removable disk interface 11 '. Data is recorded / reproduced by issuing a sector address and a read / write command from the external system side via the removable disk interface 11 '.

The control work memory 9 is a work memory used by the system controller 8 and is also used for temporary storage of management data.

[4] Operation of Removable Disk Recording / Reproducing Apparatus to which the Present Invention is Applied (1) System Initialization Next, an operation example of the apparatus shown in FIG. 6 will be described. First, an example of system initialization will be shown. When the removable disk 14 'is inserted into the removable disk drive 1', the system controller 8 issues a removable disk information read command to the removable disk drive 1 '.

Removable disk internal controller 12 '
When receiving the removable disk information read command, moves the removable disk reading device 13 ′ to the removable disk information recording area 15 and reads the removable disk information.

The removable disk information is sent to the system controller 8 via the removable disk interface 11 'and stored in the controller work memory 9.

From the received removable disk information, the system control unit 8 calculates the data size of one frame of the video data to be recorded on this removable disk, the number of recordable frames, and the sector address corresponding to this one frame, and controls it. The data is stored in the device work memory 9.

(2) Recording of video data Movie recording start key 7 of the user interface key 7
When 2 is pressed, the system controller 8 controls the A / D conversion circuit 5 and the image memory 4 to convert the video data of the input image digitized by the A / D conversion circuit 5 into the image memory 4
To be stored temporarily.

Next, the video data stored from the image memory 4 is compression-encoded by the compression encoder 2 and passed to the removable disk interface 11 '. Here, before passing the compression-encoded video data to the removable disk interface 11 ′, the system control device 8 previously sets the removable disk drive 1 ′.
The start address is notified to the removable disk internal controller 12 'therein. Then, the removable disk drive 1 ′ moves the removable disk reading device 13 ′ to the track having the start address so that video data can be recorded.

As described above, the compression-encoded video data input from the removable disk interface 11 'is recorded on the removable disk 14'.
The recording method is the same as the case of recording on the hard disk described with reference to FIGS.

That is, when the video data does not exceed the removable disk capacity, the frame data of the video data is continuously recorded in full frames. Then, the video recording stop key 73 of the user interface key 7
When is pressed, the system controller 8 sends a stop command to the compression encoder 2 and the removable disk drive 1 ', and stops moving image recording.

If the moving image recording stop key 73 is not pressed even if the image data corresponding to the capacity of the removable disk has been recorded, the system controller 8 shifts the moving image recording mode to the half frame drop recording mode. Switching is performed, and the previously recorded full frame data is overwritten with frame data obtained by dropping 1/2 frame every other frame.

If the moving image recording stop key 73 is not pressed even after the recording is completed after the half frame is dropped, the system controller 8 drops the moving image recording mode by 1/4 frame. The mode is switched to the recording mode, and the frame data in which quarter frames have been dropped every three frames is overwritten on the previously recorded data in which half frames have been dropped.

(3) Reproduction of video data When the moving picture reproduction key 71 of the user interface key 7 is pressed, the system control device 8 records whether the recorded video data is recorded in full frame or in time-lapse recording. According to the above, the removable disk interface 11 'for reproducing the recorded video data.
The removable disk internal control device 12 'of the removable disk drive 1'is notified of the reproduction start address of the desired video data via.

Removable disk internal controller 12 '
Reproduces the compression-encoded video data from the notified desired sector address, and passes the data to the decoding decoder 3 via the removable disk interface 11 '.

The decoding decoder 3 decodes and expands the compressed and encoded video data at a timing that follows it according to whether it is recorded in a full frame or in a frame skipping mode, and temporarily stores it in the image memory 4. Remember. The decoded and expanded video data stored in the image memory 4 is D
The image is D / A converted via the / A conversion circuit 6 and becomes an output image.

The above operation is continued until the video data of the time recorded on the removable disk is reproduced.
The reproducing method is the same as the case of reproducing the hard disk described with reference to FIGS. That is, the video data recorded in full frame is reproduced in full frame, the video data recorded in 1/2 frame drop is played in 1/2 frame drop, and the video data recorded in 1/4 frame drop is 1/4 frame. Play with dropped frames.

In the above description, the entire capacity of the removable disk is recorded, but it is also possible to record on a continuous part of the total capacity of the removable disk. In this case, the zoning information of the removable disk may be configured to have a recording area of video data, and the system control device 8 may be configured to read it.

Further, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention. For example, instead of halving the first frame drop,
The value may be smaller than 1/2 such as 1/3, 1/4, 1/5. On the contrary, it may be set to a value larger than 1/2 such as 2/3 (2 frames are recorded in 3 frames), 3/4, or the like. Moreover, the video data to be recorded and reproduced in the present invention may be uncompressed. Further, the recording medium is not limited to the magnetic disk, but may be a magneto-optical disk, a phase change type optical disk, a magnetic tape, or a semiconductor memory. And the video data is NT
For interlaced data such as an SC video signal, a field image may be recorded.

[0061]

As described above in detail, according to the present invention, even when video data is recorded in a full frame for a predetermined capacity of a recording medium, frame-by-frame recording is performed at a certain frame interval. The recording time can be extended by. Therefore, it is useful when it is desired to record video data whose recording time exceeds the full capacity of the recording medium, or when recording video data whose recording time is unknown.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a hard disk recording / reproducing apparatus to which the present invention is applied.

FIG. 2 is a diagram showing a pattern of full frame recording.

FIG. 3 is a diagram showing patterns of ½ frame dropping and ¼ frame dropping recording.

FIG. 4 is a diagram showing a pattern of full frame reproduction.

FIG. 5 is a diagram showing a 1 / 2-frame dropping reproduction pattern.

FIG. 6 is a diagram showing a 1/4 frame dropping reproduction pattern.

FIG. 7 is a block diagram showing a configuration of a removable disk recording / reproducing device to which the present invention is applied.

FIG. 8 is a diagram showing the concept of zone bit recording in a hard disk.

[Explanation of Codes] 1 ... Hard disk drive, 1 '... Removable disk drive, 7 ... User interface key, 8
... system control device, 14 ... magnetic disk, 14 '... removable disk

Claims (6)

[Claims] 1. When recording video data on a recording medium, all frames of the video data are recorded until recording of a capacity of a predetermined recording area of the recording medium is completed, and then frame-lapse recording is performed. A method for recording video data, which is characterized by performing. 2. A frame-dropped record is dropped by 1/2 frame.
The video data recording method according to claim 1, wherein the / 4 frame dropping is performed in order. 3. The recording medium is a magnetic disk.
Video data recording method described in. 4. The video data recording method according to claim 1, wherein the predetermined recording area is a recording area of at least a part of a recording medium. 5. A first means for recording video data on a recording medium, and a second means for managing the video data to be recorded on the first means, wherein the second means is the recording means. A video data recording apparatus, characterized in that all the frames of the video data are recorded until the recording of the capacity of a predetermined recording area of the medium is finished, and then the frame-down recording is performed. 6. A recording medium having at least information indicating a recording area of video data.