JP3371295B2 - Information recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to data of a predetermined data amount.
At the beginning of each recording unit.
Information recording that records data with additional information
Regarding equipment, for example, record video signals with high efficiency coding
It is applied to a digital VTR to be reproduced. 2. Description of the Related Art Broadcast VTRs have already adopted the D1 system and the D2 system.
Digitization based on various digital standards such as D3 and D3
Tal VTR has been commercialized. Meanwhile, consumer VTRs
In addition, various types of digital VTR
A format has been proposed. [0003] For example, the present applicant shows in FIGS.
Proposing a digital VTR with such a format first
I have. In this digital VTR, for example, NTS
When recording a C-system video signal, one frame
Is recorded on ten tracks. Figure 4 is magnetic
Indicates the track format on the tape.
From the side where the pad starts contacting the magnetic tape (left side in the figure)
In order, the signals are arranged as follows. First 45
5 bytes and the last (the magnetic head moves away from the magnetic tape
The 455-byte period on the side of the
It is said. And, 16 between the two margin areas
Substantially data is recorded during a period of 089 bytes in length.
Will be obtained. After the first margin area, the T amble
Are recorded in 60 bytes. This amble is a magnetic head
Is generated immediately after the contact of the
A little longer than other ambles in consideration of L pull-in
Has been established. During the next 237-byte period, the AT
An area F1 is formed. This area contains trucks
Pilot signals f1, f2 and fN for
And the timing sync signal fT is recorded.
You. The first 6 x 6 bytes of the A channel track
The timing sync signal fT is recorded during the
, Pilot signals f1 and fN are recorded. On the other hand, B
In channel tracks, the first 6 x 10 bytes
The timing sync signal fT is recorded during the
The pilot signals f2 and fN are recorded in
I have. However, this pilot signal f2 has four tracks.
Recorded once, pilot on remaining 3 tracks
The signal fN is recorded. The timing sync signal fT is 6 bytes
Is recorded as one unit (one block), and the first one byte is recorded.
Is the sync data, the next 2 bytes are the ID data, and the next 1
The byte is a parity IDP of the TD. The remaining one
The byte is reserved for future use. The ID data is as shown in Table 1.
Data is recorded. [Table 1] [0009] That is, the SP mode is described as having a short recording time.
Flag (SP / L) indicating the distinction between the LP mode and the long recording time
P) or indicate video, audio or subcode distinction
Two bits of data (RTYPE1, RTYPE0)
It is being recorded. Also, 4-bit data
(SYNC0 to SYNC4), the timing
The position (sync number) from the beginning of the lock signal fT
Has been made. That is, for example, the timing sync signal
6 if the number of signals fT is A channel track, B channel
In the case of the channel, there are 10
It is indicated by the lock number. Next, the principle of tracking control will be described.
I will tell. A channel track and B channel track
Are alternately arranged, and the magnetic head is
When playing a rack, the pilot signal f1 is detected.
Is done. When this pilot signal f1 is detected,
After a predetermined time has passed since
The pilot signal f2 as a crosstalk component from
Is detected. The recording length of the pilot signal f1 is
A pilot signal f2 is generated from the B channel track
It is designed to be short when detected,
Pilot signal f2 from adjacent B channel track
Is set to be longer when is detected.
You. Therefore, the length of the pilot signal f1 is
By detecting, the subsequently detected pilot signal
The signal f2 is a crosstalk component from the right track.
Or the crosstalk component from the left track
Will be recognized. Right of pilot signal f2
The crosstalk component from the track on the side
It is sampled and held. Then, the next A channel
When playing back tracks, the B channel track adjacent to the left
Level detected as a crosstalk component from the
Sample is held. And both levels are equal
Thus, the tracking control is performed. Following the ATF1 region described above, 17
An amble area is formed for a period of 6 bytes. this
The predetermined period on the front side of the amble area is an IB of 131 bytes.
G (inter block gap) region. Rear side
In the preamble area, the next audio data recording
In the area, it is necessary to detect audio data.
The clock is recorded for a period of 45 bytes. Next to this amble area is 1274 bytes.
Audio data recording area (for audio data only)
Recording area). This audio data
Audio data that is not compressed is recorded in the recording area.
Recorded as is. That is, for example, a two-channel
48kHz sampling frequency for analog audio signal
The number of quantization bits is 16 bits.
The recorded data is recorded as it is (32k
Hz, 12 bits, 4 channel data
Wear). Next to the audio data recording area,
An amble area for a period of 182 bytes is formed. this
The amble area is 6 bytes following the audio data area
Postamble period and the subsequent video data recording area
Area contains a preamble period of 45 bytes
I have. And, between the two amble areas, 13
A 1-byte IBG area is formed. The video data recording area is 13377 bytes.
And the length of the In this video data recording area
Is obtained by, for example, DCT (discrete cosine transform) processing.
In addition to recording video data compressed by
Audio data compressed by PCM etc.
It is to be recorded. Next to the video data recording area, 18
An amble area for a period of 2 bytes is formed. this
The amble area is also formed on the start point side of the video data recording area
As in the amble area being post
The amble area (6 bytes) and the preamble area (45 bytes)
And an IBG region (131 bytes) is formed between them.
Site) is formed. Postamble area is video
Following the data recording area, the next preamble area
The area precedes the subcode recording area. The subcode recording area has a period of 144 bytes.
It is set between. This area is necessary for high-speed access.
Video data recording area for important data and time code
Or video recorded in the audio data recording area
Record sub-code attached to data and audio data
It is supposed to be. Next to the subcode recording area, 220
An amble area for a byte period is formed. This
The postamble area also follows the subcode recording area.
File area (44 bytes) and the pre-ATF2 area
It is divided into an amble area (45 bytes), and
An IBG area (131 bytes) is formed. The ATF2 area has a duration of 237 bytes.
Here, the same as in the case of the ATF1 area described above is used.
One data is recorded. Further, the video data recording area,
In the audio data recording area and the subcode recording area
The data format will be described. FIG. 5 shows the video data recording area.
3 shows a data format. This video data
In the recording area, a 91-byte long sync block
Is the unit of record. At the beginning of each sync block
Records a 2-byte sync and a 3-byte identification information ID
And during the next two bytes,
Audio data (Embedded AUDI
O) is recorded. This audio file
The video data is recorded for a period of 76 bytes following the data.
The parity is arranged in the last 8 bytes. The 2-byte audio data, 76 bytes
Video data and 8-byte parity are 49 bytes
Link blocks and form a product code.
Have been. By configuring the product code in this way, the horizontal
High definition by horizontal paridi C1 and horizontal paridi C2
Error correction is possible. Here, 45 Sync Bro
Audio data and video data, and 4
The sync block is used for Paridi C2.
ing. This (78 + 8) × 49 bytes (= 421)
4 bytes) is a 13377 byte video in FIG.
3 blocks (12642 bytes) in the data recording area
Minutes are arranged. Remaining part of video data recording area
The sync SYNC and the discrimination information ID are arranged in the
And FIG. 6 shows the audio data recording area.
3 shows a data format in the present embodiment. It is shown in the figure
In this audio data recording area, FIG.
As in the video data recording area shown, the length is 91 bytes.
Data is recorded in units of sync blocks.
The first two bytes are sync and the next three bytes are discriminating information.
Information ID. And the next 78 bytes are
Dio data. Here, high-quality audio
Data is recorded. After the 78 bytes of data, 8 bytes
Parity is allocated. The 78 bytes of audio data and 8 bytes
Parity for bytes is collected for 14 sync blocks.
To form a product code. And this o
In the case of audio data, as shown in FIG.
The parity C1 in the horizontal direction is arranged at the right end, for example, and
The direction parity C1 is arranged at the center. FIG. 7 shows an example of the data recorded in the subcode recording area.
3 shows the data format of the subcode to be used. Sa
The subcode is a sync block with a length of 12 bytes.
Is recorded as The first two bytes are synced,
Are the discrimination information ID. And follow it
5 bytes are data, and subcode is recorded here.
Is done. Then, the last two bytes are used as parity. This subcode is equivalent to 12 sync blocks.
It is arranged to form a product code. However,
Only the horizontal parody C1 is used. Here, the video data recording area,
In the audio data recording area and the subcode recording area
The discrimination information ID data includes data as shown in Table 2.
Data is recorded. [Table 2] That is, the frame ID (FRID), other
(OTHERS) indicating the format of the record
2-bit data (RTYPE
1, RTYPE0) is recorded. Ma
4-bit data (SYNC11 to SYNC8)
Indicates a track number, and 1-byte data (SYN
C7 to SYNC0), the sync number in one track
Has been made to show. The above recording type 2
The bit data (RTYPE1, RTYPE0) is
As shown in FIG. 3, video data (VIDEO),
Data (AUDIO), subcode (SUB C)
ODE) and pilot signal (ATF)
I can do it. [Table 3] [0033] By the way, as described above,
After in digital VTR adopting format
-When recording, usually with a digital VTR
Is based on the position where the timing sync is detected,
Recording start position of audio data, recording of video data
Calculate the start position and subcode recording start position, and
Recording is performed, but was recorded earlier
There is a concern that data may be left unerased. For example, before performing after-recording
The recording pattern in the normal recording state as shown in FIG.
On the other hand, the IBG pattern is the shortest as shown in FIG.
The first after-recording is performed in the
FIG. 8C shows the state in which the IBG pattern is the longest.
If the second after-recording is performed
Is the data erasure remaining as shown by hatching in FIG.
Will occur. In particular, the subcode has a block length
Since it is short, unerased parts are likely to occur. Generally, in a digital VTR,
Remaining data erased by coding remains as it is during playback
Or it will be reproduced as error data
You. In particular, sub-codes with short block lengths are left unerased.
This erased data may malfunction during high-speed search operation.
It will cause the work. Accordingly, the present invention provides a conventional digital communication system as described above.
In consideration of the problems in the Tal VTR,
You can do after-recording without any
The purpose of the present invention is to provide an information recording device
You. Means for Solving the Problems The above-mentioned problems are solved.
Therefore, the present invention requires the
Position reference information is added at the beginning of each configured recording area
And divide each recording area into multiple recording sections,
The position discrimination information for specifying the recording section at each predetermined position is
Information to record multiple types of inserted data in each recording section
An information recording device that rewrites previously recorded data
The recording area including the recording section of the rewrite data
From the position reference information reproduced from the
Identify the recording segment to be played from the recording segment before the recording segment
Offset of the recording position based on the
Offset calculation means for calculating the rewrite data
Record segment obtained by reproducing the record segment before the record segment of
Record of the recording section based on the position determination information specifying the
Recording end position calculating means for calculating an end position;
Offset calculated by the set calculation means and the above record
The recording end position calculated by the end position calculation means
The recording for calculating the recording start position of the rewriting data
Equipped with head position calculation means, each position
Rewrite data based on different information
It is assumed that. According to the first aspect, data of a predetermined data amount is recorded.
In each recording area as a unit, a reference position is placed at the beginning of each recording unit.
Information recording device that records data with additional information
The data recorded in the recording area
Before the recording, the recording head position calculation means
Rewrite data based on the position reference information reproduced from the area
Calculate the recording start position of the data and rewrite the data.
U. Further, in the second invention, data of a predetermined data amount
Each recording area with data as a recording unit is divided into multiple recording sections.
Divided into predetermined data with discrimination information inserted at predetermined positions.
Multiple types of data with each data amount as a recording unit.
In an information recording device configured to record in a recording section,
When rewriting previously recorded data,
By the position calculation means, the data before the recording
Rewrite based on discrimination information obtained by reproducing the recorded section
Calculate the recording start position of data and rewrite data
Do. Further, in the third invention, a predetermined data amount
Each recording area with data as the recording unit has a leading
In addition to adding reference position information to the head, multiple recording areas
And discriminating information is inserted at predetermined positions.
Multiple types of data with a specified amount of data
Information record that records data of each kind in each record section
When rewriting previously recorded data in the
Recording of rewriting data by offset calculation means
Based on the reference position information reproduced from the recording area including the section
Of the recording section before the recording section of the rewriting data
Calculate the offset of the recording position, and
By means of the position calculating means,
The recording is performed based on the discrimination information obtained by reproducing the recording section.
Calculate the recording end position of the recording section and calculate the offset
Offset calculated by stepping and the above recording end position calculation
From the recording end position calculated by the output unit,
The position of the recording head of the rewriting data is calculated by the position calculating means.
Calculate and rewrite the data. Hereinafter, an embodiment of the information recording apparatus according to the present invention will be described.
Will be described in detail with reference to the drawings. An information recording apparatus according to the present invention
It is configured as follows. The information recording device of this embodiment is
The recording format shown in FIGS. 4 to 7 was adopted.
The present invention is applied to a digital VTR. In this embodiment, in the recording system, the input video
The video signal is digitized by the A / D converter 1 and
For example, from 4: 2: 2 to 4: 1: 1 by the number conversion circuit 2
After being converted to a signal of the basic rate, the block forming circuit 3
Processing unit (block) for block coding described later
, For example, into 8 × 8 pixel data.
In addition, the image block data that has been
The orthogonal transform such as DCT (discrete cosine transform)
Conversion and quantization are performed, and furthermore, the framing circuit 5
Image data of the frame structure on the tape recording
Is converted to And image data of frame structure
Is the parity for error correction by the parity generator 6.
After being added, it is supplied to the recording unit 8 via the multiplexer 7.
Be paid. An multiplexer (not shown) is provided to the multiplexer 7.
When audio data is supplied from the audio processing unit
In both cases, the input from the servo control system controller 9 is
SYNC, ID generated based on the imaging data and
Both of the subcodes generated by the subcode generation circuit 10
The parity code is used for parity correction by the parity generator 11.
Is added and supplied. And this multiple
The kusa 7 switches and synthesizes the above various data.
To generate recording data of the actual recording format.
It is supplied to the recording unit 8. In the information recording apparatus of this embodiment,
During after-recording, the playback system described below
Recording obtained by the provided recording start position detection unit 24
The multiplexer 7 is controlled by the start position pulse.
It is supposed to be. In the reproducing system, the reproduced data is reproduced by the reproducing unit 12.
For the reproduced signal, the time axis correction circuit 13
To remove jitter components while reproducing
Work. The image data from which the jitter component has been removed is
Whether error correction processing has been performed by the error correction circuit 14
The frame on the tape recording by the deframing circuit 15.
From image data with a system structure to a data series that can perform inverse orthogonal transformation
Returned to the decoder 16,
Is restored to the original image block data by
The image data is converted into image data of the screen
It is. Then, the error correction processing circuit 14
-Data that could not be corrected is in the error correction circuit 18.
Is corrected by interpolation, and
D / A conversion after being converted to 4: 2: 2 video signal
It is output as an analog video signal via the device 20. The audio from which the jitter component has been removed
The audio data is stored in an audio processing unit (not shown).
Initial processing is performed. The sub-core from which the jitter component has been removed is
The code is subjected to error correction processing by the error correction circuit 21.
After that, the subcode generation
System controller 23 for servo control via path 22
Given to. Further, the recording start position detecting section 24
Is the timing sync signal obtained in the playback system
The recording destination of the rewrite data based on fT and the discrimination information ID
The head position is calculated, and a recording start position pulse is generated. In this embodiment, the recording start position detection is performed.
The output unit 24 includes, as shown in FIG.
1. End position calculation circuit 42 and recording start position calculation circuit 4
3 in the reproducing section 12 of the reproducing system.
Output from the magnetic head 32 to the
33, amplifies the current and demodulates the output signal of the amplifier 33.
Demodulated by the path 34 and included in the obtained reproduced signal.
Timing sync signal for detecting the timing sync signal fT
The timing sync signal fT is output from the
While being supplied to the offset calculation circuit 41,
Detected by the SYNC detection circuit 35 included in the read / write signal
The identification information ID of the sync block to be used is the offset
It is supplied to the calculation circuit 41 and the end position calculation circuit 42.
Swelling. The offset calculating circuit 41 records the
In rewriting the sub-code,
As described above, the recording section of the rewrite data, that is, the subcode recording
The above is reproduced from the recording area for one frame including the area.
The rewriting data is rewritten based on the timing sync signal fT.
Recording section before the data recording section, that is, video data recording.
The offset of the recording position of the recording area is
Discrimination information I of the sync block obtained by reproducing the recording area
Calculated based on D. Further, the end position calculating circuit 42
Recording section before recording section of rewrite data, ie, video
The sync block obtained by reproducing the data recording area
Based on the discrimination information ID of the video data recording area.
Calculate the recording end position of the area. Then, the recording head position calculation circuit 43
Is the record calculated by the recording end position calculation circuit 42.
Recording start position of the above subcode calculated from the recording end position
The offset is calculated by the offset calculation circuit 41.
Set the actual subcode recording start position and
I do. As described above, the recording end position calculation circuit 4
2 is calculated from the recording end position calculated in Step 2.
The recording start position of the subcode is determined by the offset calculating circuit 41.
Correction with the offset calculated by
The above process of calculating the recording head position
By performing in the circuit 43, the actual sub-code
Record start position can be specified with extremely high accuracy
You. Here, compared with the above-mentioned subcode recording area,
Video data recording area with a long sync length
-When performing recording,
In the output circuit 43, the rewrite data, that is, the video data
Recording section before the recording section of the data, ie audio data
Sync block discrimination information obtained by reproducing the recording area
Sufficient recording start position of video data based on ID
Can be calculated with high accuracy, and
Video data can be rewritten. Note that, in this case, too,
Similarly, re-recording is performed from the recording area including the recording section of the rewrite data.
Based on the generated timing sync signal fT,
The recording section before the recording section of the rewrite data,
The offset of the recording position of the
Calculated by the set calculation circuit 41 to record the video data.
By correcting the recording start position, the recording start position
In the output circuit 43, the recording start position of the actual video data
Position can be specified with extremely high accuracy. Further, compared with the above subcode recording area,
And the sync length is long, and after recording
The timing sync signal fT used as a reference when
Audio closest to the recorded ATF1 recording area
Perform after-recording on the data recording area
In this case, the recording head position calculation circuit 43
Audio data based on the timing sync signal fT.
Data recording start position with sufficient accuracy.
Write audio data without leaving any
Replacements can be made. As described above, according to the present invention,
Start of each recording area consisting of data of constant data volume
Location information and add each recording area to multiple
Recording section, and the recording section is
Each type of data with the position determination information
An information recording device that records information in a recording section,
When rewriting the written data,
Position reference information reproduced from the recording area including the recording section;
Reproduction from the recording section before the recording section of the rewrite data
On the basis of the position determination information specifying the recording section to be recorded,
Offset calculation means for calculating the offset of the recording position
And the recording section before the recording section of the rewrite data
Based on position discrimination information that specifies the record categories obtained
The recording end position for calculating the recording end position of the recording section
Calculated by the position calculating means and the offset calculating means.
Calculated by the recording end position calculating means.
From the recording end position
A recording head position calculating means for calculating a head position;
Write data based on each position determination information that specifies the minute
Data writing with higher accuracy
Can be changed.
Record that is located away from the discrimination information
For the recording category, there is no
Data can be rewritten with high accuracy. Therefore, according to the present invention, data erasure remains
After-recording without any distortion
An information recording device capable of performing the above-described operations can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a configuration of a digital VTR to which the present invention has been applied. FIG. 2 is a block diagram showing a main configuration of the digital VTR. FIG. 3 is an explanatory diagram of an offset of a video data recording area by after recording in the digital VTR. FIG. 4 is an explanatory diagram of a format of a magnetic tape in the digital VTR. FIG. 5 is an explanatory diagram of a data format of a video data recording area in the format of the magnetic tape. FIG. 6 is an explanatory diagram of a data format of an audio data recording area in the format of the magnetic tape. FIG. 7 is an explanatory diagram of a data format of a subcode recording area in the format of the magnetic tape. FIG. 8 is an explanatory diagram of data remaining after erasing by after recording. [Explanation of Symbols] 7... Multiplexer 8... Recording unit 10... Sub-data generation circuit 12... Reproduction unit 24. Calculation circuit 42 Recording end position calculation circuit 43 Recording start position calculation circuit

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 20/10

Claims (1)

(57) [Claim 1] Position reference information is added to the beginning of each recording area composed of data of a predetermined data amount, and each recording area is divided into a plurality of recording sections. An information recording apparatus for recording a plurality of types of data, each having a position identification information for specifying a recording section at a predetermined position, in each recording section. In rewriting the previously recorded data, the recording section of the rewritten data Offset calculation for calculating the offset of the recording position based on the position reference information reproduced from the recording area including the recording area and the position determination information for specifying the recording section reproduced from the recording section before the recording section of the rewrite data. Means, and recording of the recording section based on position determination information for specifying the recording section obtained by reproducing the recording section before the recording section of the rewrite data. Recording end position calculating means for calculating an end position, and a recording head for calculating a recording head position of the rewritten data from the offset calculated by the offset calculating means and the recording end position calculated by the recording end position calculating means. An information recording device comprising a position calculating means, wherein data is rewritten based on each piece of position determination information for specifying a recording section.