JPH03162789A - Recording and reproducing device for digital signal - Google Patents

Abstract

PURPOSE:To have no influence upon an original picture signal even at the time of overlapping of a track of a new signal by providing a track where only a parity signal constituting the recording signal of one unit is recorded and rewriting signals with the position of this track as a sign at the time of editing. CONSTITUTION:The parity signal corresponding to digital recording signal tracks of one unit is added, and a tape is provided with a track where only the parity signal should be recorded. A discrimination signal to discriminate whether the recorded signal is a picture signal or the parity signal is recorded on each track, and the track where the parity signal is recorded is used as the sign of an editing point to perform editing recording. Thus, original picture signal tracks are not affected even at the time of the difference of track bend, and a satisfactory reproduced picture is obtained even after editing.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a digital video table recorder (hereinafter referred to as r
Regarding digital signal recording and reproducing apparatuses such as DVTRJ, etc., it specifically relates to the structure of digital signals that facilitates continuous shooting and insert editing, and the track pattern for recording the signals. [Prior Art] One way to obtain good tracking in a digital signal recording and reproducing device is to provide a control track and record a control signal (hereinafter referred to as rCTL signal) according to a vertical synchronization signal using a fixed head. play,
There is a method that uses this regenerated CTL signal. Fourth
The figure shows the track pattern. (1) is the magnetic tape, (2l) is the recording track, (22) is the control track, and (23) is the CTL signal. In a magnetic recording/reproducing device that employs the CTL signal system, a control track (
For example, Japanese Patent Application Laid-Open No. 60-79550 discloses a means for recording a continuous and uniform track pattern by controlling the tape feed using the CTL signal (23) recorded in 22). It is shown. [Problems to be Solved by the Invention] In the conventional digital signal device as described above, for example, as shown in FIG. When editing during recording and playback, for example, even if there is a track bend, the track bend of the original signal and the track bend of the new signal are generally similar, so the tracks of the original signal and the new signal Tracks have little influence on each other, allowing for relatively good editing. However, when editing tape 2 that has already been recorded, using another compatible machine rather than the same one used for recording, the track distortion of the original signal may occur, for example, as shown in Figure 5(b). Because the track curvature of the new signal and the new signal are different, the tracks overlap at the edit point, causing a situation where the original signal is lost. In particular, when tracks become narrower with a track pitch of several micrometers, as is expected to be implemented in DVTRs, the amount of bending d may be larger than the track pitch, and in such a case, the loss may occur. It is extremely difficult to restore the signal that has been lost. This invention was made to solve the above problems, and even if the original signal is lost due to overlapping new signal tracks during editing, the original image signal will not be affected. The object of the present invention is to obtain a digital signal recording and reproducing device that does not cause any problems.

[Means to solve the problem]

The digital signal recording and reproducing apparatus according to the present invention adds a parity signal for one unit of digital recording signal track, and also provides a track on the tape for recording only the parity signal, and furthermore, in each track, the recording signal is recorded as an image. The present invention is characterized in that an identification signal for identifying whether it is a signal or a parity signal is recorded, and editing and recording is performed using the track in which this parity signal is recorded as a guide for an editing point.

(Function) In this invention, the position of the track where only the variation signal is recorded is identified by the identification signal, and various edits are performed using this position as a guideline for the editing point, so even if the track curvature is different, the original signal will not be lost. do not have. [Embodiment of the Invention] An embodiment of the invention will be described below. In the recording track pattern in this embodiment, a signal for one frame (two fields) is recorded on tracks Nos. 1 to 3, and a parity signal for the signal for one frame is recorded on track No. 4. In other words, there is one variation track for every three tracks. Now, considering the current magnetic recording technology, if the tape width is 8 mm, the slant angle of the track (21) is about 5 degrees, and the track pitch is narrow, 10 μm or less, then the shortest recording wavelength is 0. If we consider it to be about 5 μm, a signal with a bit rate of about 20 Mbps can be recorded. For example, if the recording signal is a 4:2:2 component signal, the bit rate is approximately 218 Mbps, so the signal may be compressed to approximately 1/10 during recording.

A conceptual diagram of the block structure of the signal recorded on the track (21) is shown in Fig. 2(a). The image signal is divided into multiple sync blocks, and each sync block receives a synchronization signal (S
ync), index signal (I
) is recorded on the track (21) as shown in FIG.

FIG. 1 is a block circuit diagram showing an embodiment of a digital signal recording/reproducing apparatus for carrying out the present invention. When recording a signal, an analog image signal is inputted from an input terminal (7), and a recording side low-pass filter is used. (8), the signal is converted into a digital image signal by an analog/digital converter (9), and the signal is input to the recording side digital signal processing circuit (lO). This circuit performs error correction encoding, signal compression, modulation, etc., as well as interleave processing between the digital image signal and the parity signal, and then creates a recording track (21).
The digital image signal and parity signal are distributed according to the Further, a track number adding circuit (11) repeatedly generates track numbers 1 to 4 and adds them to the recording signal for each track. The IA Risa signal is sent to the recording amplifier (l2
), and the recording head (5) is amplified via the switch (13).
＾) and the recording head (6B), and the magnetic tape (1
). When reproducing a signal, the signal is read from the magnetic tape (1) by a reproducing head (3^) and a reproducing head (4B) that can move in the track width direction, and then the reproducing amplifier (l4) reads the signal from the magnetic tape (1).
After amplification, the reproduction side digital signal processing circuit (15)
Manpower is used. This circuit (15) demodulates the reproduced signal,
Performs processing such as deinterleaving and error correction decoding,
The processed signal is converted into an analog image signal by the digital/analog converter (l7), and then passed through the playback side low-pass filter (
18) and is output from the output terminal (19). In addition, various clock signals and timing signals are handled by sequence circuits (
20) Given by e. Here, the rotation speed of the rotating drum (2) is set to 3600 rpm.
Also, the playback head (3^) and the recording head (5^)
The playback head (4B) and recording head (6B) are each installed at a 90" angle.Next,
In this example, consider the case where one frame worth of insert editing is performed using a compatible machine instead of self-recording and playback. The track pattern at this time is shown in Figure 3. In the figure, track D4 is the original signal track, track P! and P
2 is the parity track of the original signal, track DI
+D2. D3 is a new signal track, and track P is a new signal parity track. In other words, DI, D
2, DS. Four tracks of Ps are used to generate one new frame's worth of signals. In actual operation, first, track numbers 1 to 4 generated by the track number addition circuit (11) are recorded in each track in advance, for example, in the ID signal section.
<． Track No.4J in the m3 diagram is the parity track. In the apparatus shown in FIG. 1, the switch <<l3> is first turned on to the reproduction side, and the original signal is reproduced. At this time, the position of the frame where you want to perform insert editing is searched using the time code signal or field address. Then, when one frame before the frame to be edited is played back, number "4" of parity track P1 is played back by the playback head (3A) or playback head (4B), and this playback signal is sent to the track number detection circuit ( l6), the switch (13) is switched to the recording side at that timing, a new signal for one frame is recorded by the recording head (5A) or the recording head (6B), and the switch (13) is switched to the recording side again. Switch to the side. At this time, since each recording head is at a position shifted by 90' from each reproduction head, the scanning start position of the recording head is exactly halfway between the variation track P and the following signal track D4. If you perform insert editing in this way, the original parity track P
, and P2 are destroyed, but the new track D+. If the track bend, such as D2, is less than half the track pitch, it will not affect the original image signal track, and a good reproduced image can be obtained even after editing. In the above embodiment, the recording signal is a digital image signal, but other signals such as a digital audio signal may be used. Further, the number of parity tracks can be arbitrarily selected as long as there is one or more tracks in one location, and the arrangement thereof can be arbitrarily set, and the same effects as in the above embodiment can be obtained. (Effects of the Invention) As described above, according to the present invention, a track for recording only a parity signal constituting one unit of recording signal is provided,
Since the position of this track is used as a guideline for rewriting when editing, there is no need to follow the track during insert recording, etc., and the configuration is simple, editing is easy, and the magnetic recording system provides good playback quality even after editing. This has the effect of providing a recording/playback device.

[Brief explanation of the drawing]

′! Fig. J1 is a block circuit diagram showing a digital signal recording/reproducing device according to an embodiment of the present invention, Fig. 2 is a schematic diagram showing a block configuration of a recording signal on a track in this embodiment, and Fig. 3 is a block circuit diagram showing a block configuration of a recording signal on a track in this embodiment. A schematic diagram showing the track pattern after insert editing. Figure 4 is a schematic diagram of the conventional track pattern. '! Figure J5 is a schematic diagram showing the state of track bending after editing in the conventional example. (3^), (4B)...playback head, (5^), (
8B)...recording head, (11)...track number addition circuit, (l3)...switch, (16)...
・Track number detection circuit. In each figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) In a digital signal recording and reproducing device that records digital signals on a medium with a rotating head, when recording, one unit of digital information and its parity signal are recorded in one track using only the parity signal, in multiple tracks. and a means for recording an identification signal attached to each track, and at the time of editing recording, a track in which a parity signal is recorded is identified from the reproduced identification signal, and editing recording is started using this track position as a reference for an editing point. A digital signal recording and reproducing device characterized by comprising: means.