JPH1011893A - Magnetic recording and reproducing device and magnetic reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent malfunction of a decoder, etc., even when a consecutive recording part is reproduced, by resetting a packet output control circuit of the decoder and the reproducing device at a consecutive joint when a consecutively recorded medium is reproduced. SOLUTION: When a start flag 67 is detected by a flag detecting circuit 22 during reproduction of a track, this is outputted as a flag detecting signal 114 to a system controller 27. Since packet output timing of an editing point part is delayed, for instance, by eleven tracks, a packet output control signal 100 is once turned into L before and after the editing point output timing by the system controller 27, and an output of the output control circuit 26 is stopped, and is reset by control of a buffer 25. Thus, the packet output is stopped before and after the editing point, and a packet of discontinuity on time base is prevented from being outputted as it is to the decoder, and the output control circuit 26 is reset to its initial state, so that malfunction of an overflow of the buffer, etc., can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the recording and reproduction of digital compressed video signals for home use, and more particularly to a magnetic recording and reproducing apparatus and a magnetic reproducing apparatus suitable for recording and reproducing digital compressed signals having a packet structure. .

[0002]

2. Description of the Related Art As a device for recording and reproducing a digital compressed video signal, there is a digital information reproducing device described in Japanese Patent Application Laid-Open No. 7-272414. This apparatus records the input compressed digital information signal as it is, and outputs the same compressed digital information signal to a decoder or the like at the time of reproduction to a decoder or the like at the time of reproduction, and decompresses the decoder into, for example, a video signal and an audio signal. Had become.

As a compression technique, for example, MPEG (Movi)
ng Picture Expert Grope) is known. The MPEG system is a system for transmitting a difference signal with respect to a reference frame using correlation between frames. For this reason, the data amount of each frame is different, and the frame of the recording / reproducing apparatus and the frame of the video cannot be synchronized.

In some cases, a digital information signal is transmitted in a packet structure as shown in FIG. In the figure, 40 is a packet, 41 is a header added to the head of each packet, and 42 is a compressed information signal.

[0005] Each packet is transmitted in bursts, not at regular intervals. The time interval is added with information called a time stamp indicating a time difference from a certain time to the actual transmission. In FIG. 2, the time stamp 42 is shown as a 20-bit time stamp. The numbers 3, 4, 6,... Attached to each packet indicate the time stamp 42.

When a digital signal having the packet structure shown in FIG. 2 is recorded and reproduced, a time stamp 42 added to each packet 40 is recorded at the same time. It is necessary to output each packet 40 at the same time interval as the time.

[0007]

In a recording / reproducing apparatus for a digital signal having a packet structure having a time stamp as described above, when reproducing a recording medium on which editing such as a splicing recording is performed, before and after the editing point. The packets become discontinuous, and the continuity of the time stamp is also lost.

In the MPEG system, as described above, since the video frame and the frame of the recording / reproducing apparatus are asynchronous, it is possible to control where the break of the edit point (called the edit point) comes in the frame of the MPEG data. No, MPEG
Data of different frames are discontinuously connected in the middle of the data frame. For this reason, the MPEG decoder may malfunction, it may take time to obtain video and audio, or the system operation may not recover unless the worst reset is performed. Since the output timing of the packet is controlled, the time stamp suddenly becomes discontinuous at the editing point, so that a circuit for controlling the time stamp may cause an operation failure such as a buffer overflow.

In the above prior art, no consideration is given to the discontinuity of the packet and the discontinuity of the time stamp that occur when reproducing the portion of the edit point such as the joint recording.

It is an object of the present invention to provide a magnetic recording / reproducing apparatus and a magnetic reproducing apparatus in which a decoder or the like does not malfunction even when a joint recording portion is reproduced.

[0011]

In order to achieve the above object, an apparatus for recording and reproducing a digital signal transmitted in a packet structure in frame units together with a time stamp indicating transmission time information of the packet is provided. Input means for inputting, information adding means for adding recording start information indicating the start of recording to the digital signal input from the input means, and recording means for recording the digital signal with the recording start information added on a recording medium. A reproducing unit that reproduces the recording medium; an information detecting unit that detects the recording start information from the reproduced signal reproduced by the reproducing unit and outputs an information detection signal; and a storage unit that stores the reproduced signal. Time stamp detecting means for detecting the time stamp from a storage signal stored in the storage means; Output control means for generating a timing for reading a storage signal from the storage means based on time information indicated by the detection time stamp detected by the tamping detection means, and reset means for resetting the output control means based on at least the information detection signal; Output means for outputting a signal read from the storage means is provided.

When the recording start information is not recorded / reproduced, an ID adding means for adding frame information indicating the number of the frame to the digital signal input from the input means, and a reproduced signal reproduced by the reproducing means. An ID detecting means for detecting the frame information; and a continuity for outputting an ID discontinuity signal when the continuity of the detected frame information detected by the ID detecting means for each frame is detected and the frame is determined to be discontinuous. Sex detection means, and at least I
Reset means is provided for resetting the output control means in response to the D discontinuous signal.

Further, the reset means includes reset output means for outputting a reset request signal at least based on the information detection signal or the ID discontinuity signal and outputting the reset request signal generated by the reset means.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a digital VTR for home use according to the present invention. In the system configuration shown in FIG. 14, digital broadcasting compressed by, for example, MPEG or the like is converted into a packet structure to be described later. It is recorded and reproduced as it is.

In FIGS. 1 and 14, reference numeral 2 denotes a receiving device for receiving a compressed digital signal broadcast from a satellite or the like and decoding such as decompression, 1 denotes an antenna, and 3 denotes a receiving device 2.
A recording / reproducing apparatus for recording / reproducing the digital signal received by the device, 4 a receiving circuit, 5 a time stamp generating circuit, 6 a switch, 7 a decoder, 8 a recording packet output terminal,
9 is a recording packet input terminal, 10 is a reproduction packet input terminal, 11 is a reproduction packet output terminal, 14 is a video output terminal, 15 is a recording processing circuit, 16 is a flag addition circuit, 17
Is a recording amplifier, 18 is a rotary head, 19 is a magnetic tape,
20 is a reproduction amplifier, 21 is a reproduction processing circuit, 22 is a flag detection circuit, 23 is a storage circuit, 24 is a servo, 25 is a buffer, 26 is an output control circuit, and 27 is a system controller.

In the receiving apparatus 2, the M received by the antenna 1
The digital signal compressed by PEG or the like is subjected to demodulation processing, channel selection, descrambling processing and the like by the receiving circuit 4. When decoding the received signal in real time, the switch 6 selects a, performs processing such as decompression by the decoder 7, and converts the signal into a video signal and an audio signal.
Output from the video output terminal 14.

At the same time, the time stamp generation circuit 5
Thus, time axis information called a time stamp is added, and the signal is output from the recording packet output terminal 8 as a signal having the packet structure shown in FIG. In FIG.
Is a packet, 41 is a header added to the head of each packet, and 43 is a compressed information signal.

Each packet is transmitted in bursts, not at regular intervals. The time interval is added with information called a time stamp indicating a time difference from a certain time to actual transmission. In FIG. 2, the time stamp 42 is shown as a 20-bit time stamp.
The last 20 bits of the byte (32 bits) are used as the time stamp 42. The numbers 3, 4, 6,... Attached to each packet are time stamps 42.
Is shown. That is, for example, the time interval indicated by T is 1
When a certain time is set to 0, the transmission timing time of each packet is indicated as a time stamp 42.

When recording on the recording / reproducing apparatus 3, the time stamp 42 added by the time stamp generating circuit 5
Is input to the recording processing circuit 15 of the recording / reproducing apparatus 3 via the recording packet output terminal 8 and the recording packet input terminal 9.

FIG. 3 shows a recording format in the recording / reproducing apparatus 3, which shows one track recorded on the magnetic tape 19 by rotating the rotary head 18 by 180 °. In the figure, reference numeral 50 denotes a margin 1 and preambles 1, 5
1 is a subcode area, 52 is a postamble 1 and a preamble 2, 53 is a main area, 54 is a postamble 2 and a margin 2. Also, the main area 53
Among them, 55 is a compressed digital signal, and 56 is a parity for error correction. The parity 56 is added to the compressed digital signal 55 for six tracks, and is completed in six tracks.

FIG. 4A shows a format of a subcode recorded in the subcode area 51, and shows one block. In the figure, reference numeral 61 denotes a synchronization signal indicating the beginning of a block; 62, IDs 1 and 6 in which track numbers indicating the absolute number of tracks from the beginning of the magnetic tape 19 are recorded
Reference numeral 3 denotes IDs 2 and 6 in which a start flag and the like described later are recorded
4 is an IDP which is a parity for error detection of ID1 (62) and ID2 (63); 65 is pack data having additional information for a signal recorded in the main area 53;
Is a parity for error detection and correction of the pack data 65. (B) is a recording format of main data recorded in the main area 53, which indicates one block. In the figure, reference numeral 71 denotes a synchronization signal indicating the head of a block, 72 denotes SEQ77 and T indicating frame information and the like.
IDs 1 and 73 in which the PA 78 and the like are recorded are IDs 2 and 7 which are block addresses indicating the positions of the blocks in the track.
Reference numeral 4 denotes an IDP which is an error detection parity of ID1 (72) and ID2 (73); 75, main data such as a compressed video signal; and 76, an error detection and correction parity of the main data 75. In the lower part of FIG. 4 (b), reference numeral 180 denotes an unused area, and 79 denotes a block address indicating a block position. The number in parentheses indicates the number of bits.

The recording and reproducing operations in the recording and reproducing device 3 will be described.

At the time of recording, the signal of the packet structure shown in FIG. 2 inputted from the recording packet input terminal 9 is added with a parity 56, a parity 76, etc. by the recording processing circuit 15,
ID1 (72), ID2 (7
3), the IDP (74) is added, and the synchronization signal 71
Are added, modulation processing is performed, and the data is recorded in the main area 53 of the magnetic tape 19 by the rotary head 18 via the recording amplifier 17. Further, the pack data 65 is input from the system controller 27 to the flag adding circuit 16, and the pack data 65 is input to the flag adding circuit 16 by ID1 (62),
ID2 (63) and IDP (64) are added, and a synchronization signal 61 is added by the recording processing circuit 15, and the recording amplifier 1
The recording data is recorded in the subcode area 51 of the magnetic tape 19 by the rotary head 18 via.

At the time of reproduction, the magnetic tape 19 is
8 and reproduces the reproduced signal via the reproduction amplifier 20.
It is sent to the reproduction processing circuit 21. In the reproduction processing circuit 21,
The head of the block is detected by the synchronization signals 61 and 71,
It is stored in the storage circuit 23. The signals stored in the storage circuit 23 are converted by the reproduction processing circuit 21 into parities 56 and 76.
, An error is detected and corrected in the main data 75, and an error is detected and corrected in the pack data 65 using the parity 66. The flag detection circuit 22 detects ID1 (62) and ID2 (63) in the subcode area 51,
Error detection using the DP 64
D1 (72), ID2 (73) detection, and error detection using IDP74 are respectively performed, and output to the system controller 27 together with the pack data 65.

The error detection and correction using the parity 66 and the parity 76 are completed in one block, and may be performed before the data is stored in the storage circuit 23.

Error correction and detection by parity 56 (C2
Since the decoding is completed for six tracks, it is performed after reproducing six tracks. After C2 decoding for 6 tracks,
Through the output control circuit 26, a time stamp temporarily stored in the buffer 25 and included in the main data 75 is detected, and each packet is read out from the buffer 25 at a time interval indicated by the time stamp. 11 is output.

FIG. 5 shows a track timing at the time of reproduction. 90 is a head switching signal indicating the rotation cycle of the rotary head 18, 91 is a reproduction signal input to the reproduction processing circuit 21, and 92 is a parity 56. , 93 is a packet output signal output from the output control circuit 26. As shown in the figure, the hatched reproduction signal 94 for six tracks is subjected to C2 decoding in the next approximately four tracks 95, and is output between six tracks 96 after one track. Therefore, the signal reproduced from the magnetic tape 19 is output as a packet after 11 tracks.

When the receiving apparatus 2 processes the reproduced video of the recording / reproducing apparatus 3, the signal input from the reproduced packet input terminal 10 is sent to the decoder 7 by selecting the switch 6 to b and subjected to decoding processing and the like. To obtain a video signal and an audio signal.

Next, the operation of the output control circuit 26 will be described with reference to the block diagram shown in FIG. 6 and the timing chart shown in FIG. 6, reference numeral 80 denotes an input address generation circuit for controlling an address when a signal read from the storage circuit 23 is temporarily stored in the buffer 25, and reference numeral 81 denotes an output address generation for controlling an address when a signal is read from the buffer 25. A circuit 82, a time stamp detection circuit for detecting the time stamp 42; 84, a time stamp counter for generating a time serving as a reference for the time stamp 42;
Is a comparison circuit for detecting whether or not the time stamp 102 detected by the time stamp detection circuit 82 and the time 103 generated by the time stamp counter 84 match. 7, reference numeral 100 denotes a packet output control signal for controlling the output of a packet, 101 denotes an output address generated by an output address generation circuit, 102 denotes a time stamp detected by a time stamp detection circuit 102,
03 is time axis information generated by the time stamp counter 84.

At the start of packet output, a packet output control signal 100 rises from the system controller 27. The output control circuit 26 is initialized based on the rise of the packet output control signal 100, and the operation starts. First, the first time stamp 104 (in FIG. 7, “3”) detected by the time stamp detection circuit 82 is loaded into the time stamp counter 84. Hereinafter, the time stamp counter 84 is a 20-bit counter, and has a prescribed frequency (for example, 27 MHz).
Repeats the count-up operation. After the output of the first packet, the output address advances, the time stamp of the next packet is read from the buffer 25, and the comparison circuit 83 determines whether or not it matches the time 103 indicated by the time stamp counter 102. If they match, the packet is read from the buffer 25 and output. If they do not match, the process waits until the value 103 of the time stamp counter matches the detection time stamp 102, and when they match, reads out the packet from the buffer 25 and outputs it.

As a result, it is possible to output packets at the time interval input at the time of recording.

Next, connection recording according to the present invention will be described.

In the splicing recording, recording is continuously performed on an already recorded portion. For example, during recording,
This corresponds to the case where the pause button (REC PAUSE) is pressed, and the recording stop is released to resume the recording.
A problem arises when reproducing the medium recorded in this way, especially in the case of a digital compressed signal.

FIG. 12 shows a conventional recording / reproducing apparatus.
FIG. 13 shows the reproduction timing of a connection portion (hereinafter referred to as an edit point), and FIG. 13 shows the operation timing of the output control circuit 26 at that time. In both figures, data before the edit point 140 is hatched. The editing points are shown in FIG.
In the case where the C2 decoding comes to the end of the 6 tracks as shown in FIG. 2, continuous playback is performed in the joint recording, and no error is detected by the error detection using the parity 76 or the C2 decoding. At the discontinuity 141
The packet output 93 is output to the receiving device 2 in a state where the continuity is lost. For this reason, the decoder 7 of the receiving device 2 malfunctions, generates a large noise on the video and audio, hangs up, takes a long time to obtain the video and audio, and cannot recover without the worst reset. In some cases.

As shown in FIG. 13, the output control circuit 2
In FIG. 6, before and after the discontinuity point, the detection time stamp 10
2 is lost and the values before and after the edit point have no correlation. Therefore, the value 103 of the time stamp counter 84 cannot be matched, the output from the buffer 25 cannot be guaranteed, and an overflow state occurs. A reset may be required.

In the conventional device, since no error is detected,
This discontinuity cannot be detected, and it is impossible to prevent malfunctions on the recording / reproducing device side and the receiving device side.

Therefore, in the present invention, a start flag is recorded on the magnetic tape 19 for a fixed time at a recording start portion (including a start from a recording pause), and the start flag is used during reproduction. , The editing point is detected, and the recording / reproducing device 3 and the receiving device 2 are reset.

As shown in FIG. 4A, the start flag is written in the MSB 1 bit (67) of ID2 (63). At the start of recording, the start flag is recorded, for example, over 300 tracks. It is used for.

FIG. 8 shows the reproduction timing when reproducing the recording medium in which the start flag 67 is recorded at the edit point. Here, for the sake of simplicity, the start flag 67 indicates 30 tracks (track 112 to track 1) at the start of recording.
13). FIG.
Similarly to the above, the data portion before the edit point is hatched. During reproduction of the track 112, the flag detection circuit 22
When the start flag 67 is detected, a flag detection signal 114 is output to the system controller 27.
Since the packet output timing of the edit point portion is delayed by 11 tracks as described above, the system controller 6
7 is before and after the edit point output timing 117 (115 to 11).
In 6), the packet output control signal 100 is set to L once, the output of the output control circuit 26 is stopped, and the control of the buffer 25 is reset. As a result, the output of the packet is stopped before and after the edit point, and the packet that is not continuous on the time axis is prevented from being output to the decoder 6 as it is. The circuit 26 can be reset to the initial state, thereby preventing an operation failure such as a buffer overflow.

In the packet output stop section, if the packet is applied to the entire start flag detection section, the packet stops for a long time. Therefore, the time from the detection start track is determined as shown in FIG. Only stop. The actual output of the packet may be stopped just from the output timing of the edit point.

Note that the start flag 67 is the IDP 64
Error detection is performed, and the reliability is generally low. Therefore, if the start flag 67 recorded for each block is continuously matched or majority matched within one track, the reliability can be improved. In addition, the reliability can be further improved by obtaining continuous matches over several tracks. In FIG. 8, by detecting the start flag for three consecutive tracks, it is determined that the editing point is set. This match detection processing may be performed by either the flag detection circuit 22 or the system controller 27.

On a recording medium on which the start flag 67 is not recorded, an edit point cannot be detected. Therefore, in the present invention, a method of using the frame information recorded in ID1 (72) in the main area 53 can be considered.

In the ID1 (72) in the main area 53, the TPA7 which increases from 0 to 2 every two tracks is provided.
8 or SE that increases every 6 tracks from 0 to 15
Frame information Q77 is recorded. Therefore, at the editing point, there is a possibility that these pieces of frame information will not be continuous.

For example, as shown in FIG.
When the joint recording is performed at 2, SEQ77 becomes discontinuous. In the case of the edit point 123, the TPA is discontinuous. If the flag detection circuit 22 detects the discontinuity between SEQ and TPA, the flag abnormality detection circuit 22 outputs an ID abnormality signal 121 to the system microcomputer 27. The system microcomputer 27 is shown in FIG.
Similarly to the above, the packet output control signal is dropped to L, the packet output is stopped, and the output control circuit 26 is initialized.

These SEQ77 and TPA78 are IDP
Since only the error detection by 74 is performed, the reliability is low similarly to the start flag 67. Therefore, as in the case of the start flag, reliability can be improved by detecting coincidence in a track, majority decision, coincidence detection in continuous tracks, and the like. In FIG. 9, when two tracks are detected consecutively, the ID abnormal signal 1
21 is output to the system microcomputer 27.

As described above, the editing point can be detected even on a medium in which the start flag is not recorded. However, since the TPA 78 and the SEQ 77 may accidentally continue at the editing point, the start flag 67 is set. It is more reliable to use.

In the above description, the output stop and initialization in the recording / reproducing apparatus 3 have been described. However, this alone has a problem of packet discontinuity. That is,
For example, in FIG. 8, the packets before the timing 115 and the packets after the timing 116 are not continuous on the time axis, and there is a risk that the decoder 7 of the receiving apparatus 2 may malfunction if the packets are not changed. Therefore, as shown in the block diagram shown in FIG. 10 and the timing diagram shown in FIG. 11, in the packet suspension section (115 to 116), the system controller 27 outputs the reset request signal 131 to the receiving device 2, and By resetting to 7, a malfunction can be reliably prevented, and a correct video signal and audio signal can be obtained immediately after editing. In FIG.
Is a request signal output terminal, and 13 is a request signal input terminal.

The length of the packet suspension section (115 to 116) may be a time interval enough to cover the transmission time of the reset request signal 131 and the time required for resetting the decoder 7.

In the above description, the processing by the start flag and I
D has been described separately.
If either of the discontinuities of D is detected, it may be determined as an edit point.

Although a magnetic tape has been used in the above description, the present invention can be implemented with a recording medium such as a magnetic disk.

The time stamp 42 indicates that the examination device 2
However, this may be added by the recording / reproducing device 3 for recording. In this case, the recording / reproducing apparatus 3 may be provided with the time stamp generating circuit 5. Further, in the mode in which the input data includes the time stamp, the input time stamp is recorded. In the mode in which the input data does not include the time stamp, the time stamp generation provided in the recording / reproducing apparatus 3 is provided. The time stamp generated by the circuit 5 may be recorded.

In FIG. 2 and the like, for the sake of simplicity, the time stamp step is set to the minimum interval between packets.
7 MHz), the spacing between packets is much wider.

In FIG. 1 and FIG. 10, the recording packet and the reproduction packet are transmitted from different terminals through different signal lines, respectively, but are transmitted from the same terminal using the same signal line for both input and output. May be. In FIG. 10, the request signal 1
Although 31 is transmitted using independent signal lines and terminals, it may be transmitted by multiplexing it on a packet signal line.

As data to be recorded on the recording medium,
When a general digital signal other than the compressed digital signal is used, the output control circuit is initialized, but the packet output need not necessarily be stopped.

[0056]

According to the present invention, in an apparatus for recording / reproducing a compressed digital signal having a packet structure, a recording medium recorded by splicing (for example, when recording is temporarily stopped and recording is restarted again). When playing back, at the joint (edit point), reset the decoder and the packet output control circuit of the playback device to prevent malfunction, prevent video and audio noise at the edit point, and prevent decoder hang-up. And the video and audio after the editing point can be obtained immediately.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a magnetic recording / reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing a format of a packet of a compressed digital signal.

FIG. 3 is a diagram showing a track format of the magnetic recording / reproducing apparatus.

FIG. 4 is a diagram showing a block format of the magnetic recording / reproducing apparatus.

FIG. 5 is a timing chart showing a reproduction timing of the magnetic recording / reproducing apparatus.

FIG. 6 is a block diagram of an output control circuit in the magnetic recording / reproducing device.

FIG. 7 is a timing chart showing operation timings of the output control circuit.

FIG. 8 is a timing chart showing a first operation at an edit point of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 9 is a timing chart showing a second operation at an edit point of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 10 is a block diagram showing another embodiment of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 11 is a timing chart showing operation timings of another embodiment of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 12 is a timing chart showing a conventional operation at an editing point of the magnetic recording / reproducing apparatus.

FIG. 13 is a timing chart showing a conventional operation at an editing point of the output control circuit.

FIG. 14 is a system diagram showing a system configuration of a magnetic recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

2 receiving apparatus, 3 recording and reproducing apparatus, 5 time stamp generating circuit, 15 recording processing circuit, 16 flag adding circuit, 21 reproducing processing circuit, 22 flag detecting circuit, 25
... Buffer, 26 ... Output control circuit, 27 ... System controller, 42 ... Time stamp, 67 ... Start flag, 77 ... SEQ, 78 ... TPA, 80 ... Input address generation circuit, 81 ... Output address generation circuit, 82 ... Time stamp Detection circuit 83 ... comparison circuit 84 ... time stamp counter 100 ... packet output control signal 120
... ID abnormality detection, 131 ... Reset request signal

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoshio Yamada 1410 Inada, Hitachinaka-shi, Ibaraki Pref., Hitachi, Ltd. Visual Information Media Division (72) Inventor Nobutaka Amada 1410 Inada, Hitachinaka-shi, Ibaraki Hitachi, Ltd. Information Media Division (72) Inventor Hiroo Okamoto 1410 Inada, Hitachinaka City, Ibaraki Prefecture Hitachi, Ltd. Visual Information Media Division

Claims (22)

[Claims] An apparatus for recording and reproducing a digital signal transmitted in a packet structure together with a time stamp indicating transmission time information of the packet, an input means for inputting the digital signal, and a digital signal input from the input means. Information adding means for adding recording start information indicating a recording start point to the recording medium; recording means for recording a digital signal to which the recording start information is added on a recording medium; reproducing means for reproducing the recording medium; Information detecting means for detecting the recording start information from the reproduced signal reproduced by the means and outputting an information detection signal; storage means for storing the reproduced signal; and detecting the time from the stored signal stored in the storage means. A time stamp detecting means for detecting the stamp; and a time stamp detected by the time stamp detecting means. Output control means for generating a timing for reading a storage signal from the storage means based on time information to be output, reset means for resetting the output control means at least based on the information detection signal, and outputting a signal read from the storage means The information adding means adds the recording start information only for a predetermined time when the recording means starts recording on the recording medium, and the reset means detects the recording start information by at least the information detecting means. A magnetic recording / reproducing apparatus, wherein the output control means is reset when it is performed. 2. The reset means outputs a discontinuity detection signal indicating that there is a temporally discontinuous packet in an output packet output from the output means, at least in accordance with the information detection signal. Comprising a control signal output means for outputting the discontinuity detection signal generated in
At least when the recording start information is detected by the information detecting means, it indicates that an external or internal system has a temporally discontinuous packet in an output packet output from the output means. The magnetic recording / reproducing apparatus according to claim 1. 3. The information detection means outputs the information detection signal when the recording start information is detected m times (m is a natural number of 2 or more) consecutively. Or a magnetic recording / reproducing apparatus according to claim 2. 4. The output control means includes reference time stamp generating means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detecting means, and the reset means includes at least the information 4. The magnetic device according to claim 1, wherein said reference time stamp generating means is reset by initializing said reference time stamp generating means with a detection time stamp detected by said time stamp detecting means. Recording and playback device. 5. An apparatus for recording and reproducing a digital signal transmitted in a packet structure together with a time stamp indicating transmission time information of the packet on a recording medium, wherein the frame having a fixed time unit is provided. Frame generating means for generating a cycle, input means for inputting the digital signal, and ID adding means for adding frame information indicating the number of the frame generated by the frame generating means to the digital signal input from the input means Recording means for recording the digital signal to which the frame information has been added on a recording medium in frame units; reproducing means for reproducing the recording medium; and reproducing the frame information from the reproduced signal reproduced by the reproducing means. ID detecting means for detecting, and the file of the detected frame information detected by the ID detecting means. Continuity detecting means for outputting an ID discontinuity signal when the continuity of each of the frames is detected and it is determined to be discontinuous; storage means for storing the reproduced signal; and storage means for storing the storage means. A time stamp detecting means for detecting the time stamp from the signal; an output control means for generating a timing for reading out a storage signal from the storage means based on time information indicated by the detected time stamp detected by the time stamp detecting means; Reset means for resetting the output control means by the ID discontinuity signal, and output means for outputting a signal read from the storage means, wherein the reset means
A magnetic recording / reproducing apparatus, wherein the output control means is reset when the frame information detected by the ID detection means is discontinuous. 6. The reset means outputs a discontinuity detection signal indicating that there is a temporally discontinuous packet in an output packet output from the output means, based on at least the ID discontinuity signal. Comprising a control signal output means for outputting the discontinuity detection signal generated in
At least when the frame information detected by the ID detection means is discontinuous, it indicates that there is a temporally discontinuous packet in an output packet output from the output means in an external or internal system. Claim 5
The magnetic recording and reproducing apparatus according to claim 1. 7. The output control means includes reference time stamp generating means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detecting means. 7. The magnetic recording / reproducing apparatus according to claim 5, wherein the reference time stamp generating means is reset by initializing the reference time stamp generating means with the detected time stamp detected by the time stamp detecting means in response to an ID discontinuity signal. apparatus. 8. An apparatus for recording and reproducing a digital signal transmitted in a packet structure along with a time stamp indicating transmission time information of the packet on a recording medium, wherein the frame having a fixed time unit is provided. Frame generating means for generating a cycle, input means for inputting the digital signal, information adding means for adding recording start information indicating a recording start point to the digital signal input from the input means, and input from the input means. ID adding means for adding frame information indicating the number of the frame generated by the frame generating means to the digital signal; and recording the recording start information or the digital signal added with the frame information on a recording medium in units of the frame. Recording means for recording, reproduction means for reproducing the recording medium, and reproduction means Information detection means for detecting the recording start information from the generated reproduction signal and outputting an information detection signal; ID detection means for detecting the frame information from the reproduction signal reproduced by the reproduction means; and ID detection means Continuity detecting means for detecting continuity of the detected frame information detected for each frame in each frame and outputting an ID discontinuity signal when it is determined that the frame is discontinuous; storage means for storing the reproduced signal; A time stamp detection unit for detecting the time stamp from the storage signal stored in the storage unit, and a timing for reading the storage signal from the storage unit based on time information indicated by the detection time stamp detected by the time stamp detection unit. Output control means for generating, and at least the output control means by the information detection signal or the ID discontinuity signal. Reset means for resetting, and output means for outputting a signal read from the storage means, wherein the reset means is provided when at least the recording start information is detected by the information detecting means, or when the ID detecting means is used. And resetting the output control means when the frame information detected in step (1) is discontinuous. 9. The reset means outputs a discontinuity detection signal indicating that there is a temporally discontinuous packet in an output packet output from the output means at least by the information detection signal or the ID discontinuity signal. And a control signal output means for outputting the discontinuity detection signal generated by the reset means, wherein at least the recording start information is detected by the information detection means or
When the frame information detected by the D detection means is discontinuous, it indicates that an external or internal system has a temporally discontinuous packet in an output packet output from the output means. A magnetic recording / reproducing apparatus according to claim 8. 10. The output control means includes reference time stamp generation means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detection means, and the reset means includes at least the reset time means. By the information detection signal or the ID discontinuity signal,
10. The magnetic recording / reproducing apparatus according to claim 8, wherein the reference time stamp generating means is reset by initializing with the detected time stamp detected by the time stamp detecting means. 11. The magnetic recording / reproducing apparatus according to claim 1, wherein said time stamp is inputted from said input means. 12. The digital signal having the packet structure described above,
11. The apparatus according to claim 1, further comprising a time stamp generating circuit for measuring a time input from the input means, wherein the time stamp is a generated time stamp generated by the time stamp generating circuit. A magnetic recording / reproducing apparatus according to any one of the preceding claims. 13. The digital signal having the above-mentioned packet structure,
A time stamp generation circuit for measuring a time input from the input means, a first mode for inputting a time stamp from the input means, and a second mode for not inputting the time stamp from the input means; In the first mode, the input time stamp input from the input means is recorded on the recording medium, and in the second mode, the generation time stamp generated by the time stamp generation circuit is recorded on the recording medium. The magnetic recording / reproducing apparatus according to any one of claims 1 to 10, wherein: 14. An apparatus for reproducing a recording medium on which a digital signal transmitted in a packet structure, a time stamp indicating transmission time information of the packet, and recording start information indicating recording start are reproduced. Reproducing means, information detecting means for detecting the recording start information from the reproduced signal reproduced by the reproducing means and outputting an information detection signal, storage means for storing the reproduced signal, and information stored in the storage means. Time stamp detection means for detecting the time stamp from the stored signal, and output control means for generating a timing for reading the storage signal from the storage means based on time information indicated by the detected time stamp detected by the time stamp detection means Resetting means for resetting said output control means by at least said information detection signal. Output means for outputting a signal read from the storage means, wherein the reset means resets the output control means when at least the recording start information is detected by the information detection means. Magnetic playback device. 15. The reset means outputs a discontinuity detection signal indicating that there is a temporally discontinuous packet in an output packet output from the output means at least in accordance with the information detection signal. And a control signal output means for outputting the discontinuity detection signal generated in the step (a). When at least the recording start information is detected by the information detection means, an output output from the output means to an external or internal system. 15. The magnetic reproducing apparatus according to claim 14, wherein the packet indicates that there is a temporally discontinuous packet. 16. The output control means includes reference time stamp generating means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detecting means, and the reset means includes at least the information 16. The magnetic reproducing apparatus according to claim 14, wherein a reset signal is reset by initializing the reference time stamp generation means with a detection time stamp detected by the time stamp detection means in response to a detection signal. 17. A recording medium on which a digital signal transmitted in a packet structure, a time stamp indicating transmission time information of the packet, and frame information indicating a frame number composed of a fixed time are recorded in units of the frame. A reproducing unit that reproduces the recording medium; an ID detecting unit that detects the frame information from a reproduction signal reproduced by the reproducing unit; and the frame of the detected frame information detected by the ID detecting unit. Continuity detecting means for outputting an ID discontinuity signal when the continuity of each is detected and it is determined that the signal is discontinuous; storage means for storing the reproduction signal; and storage signals stored in the storage means. A time stamp detecting means for detecting the time stamp, and a detection time stamp detected by the time stamp detecting means. Output control means for generating a timing for reading out a storage signal from the storage means based on the time information shown in (1), reset means for resetting the output control means at least by the ID discontinuity signal, and read out from the storage means Output means for outputting a signal,
The magnetic reproducing apparatus, wherein the reset means resets the output control means when the frame information detected by the ID detection means is discontinuous. 18. The apparatus according to claim 18, wherein said reset means includes at least one of
A discontinuous detection signal indicating that there is a temporally discontinuous packet in the output packet output from the output unit is output by the D discontinuous signal, and the discontinuous detection signal generated by the reset unit is output. A control signal output unit that outputs a packet that is temporally discontinuous in an output packet output from the output unit to an external or internal system when at least the frame information detected by the ID detection unit is discontinuous. 18. The magnetic reproducing apparatus according to claim 17, wherein the magnetic reproduction device indicates that there is. 19. The output control means includes reference time stamp generation means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detection means, and the reset means includes at least the reset time means. 18. The method according to claim 17, wherein the reference time stamp generation unit is reset by initializing the reference time stamp generation unit with a detection time stamp detected by the time stamp detection unit in response to an ID discontinuity signal.
9. The magnetic reproducing apparatus according to 8. 20. A digital signal transmitted in a packet structure, a time stamp indicating transmission time information of the packet, recording start information indicating recording start, and frame information indicating a frame number composed of a fixed time are frame units. Device for reproducing the recording medium recorded in
A reproducing unit that reproduces the recording medium; an information detecting unit that detects the recording start information from the reproduced signal reproduced by the reproducing unit and outputs an information detection signal; and a reproducing unit that reproduces the information from the reproduction signal reproduced by the reproducing unit. ID for detecting frame information
Detection means; continuity detection means for detecting continuity of the detected frame information detected by the ID detection means for each frame and outputting an ID discontinuity signal when it is determined that the information is discontinuous; , A time stamp detecting means for detecting the time stamp from the storage signal stored in the storing means, and a storing means based on time information indicated by the detected time stamp detected by the time stamp detecting means. Output control means for generating a timing for reading a storage signal from the memory, reset means for resetting the output control means at least by the information detection signal or the ID discontinuity signal, and outputting a signal read from the storage means An output unit, wherein the reset unit is configured to output the recording start information by at least the information detection unit. When detected, or magnetic reproducing apparatus, characterized in that the frame information detected by the ID detection means for resetting said output control means when the discontinuity. 21. The reset means, at least by the information detection signal or the ID discontinuity signal, outputs a discontinuity detection signal indicating that there is a temporally discontinuous packet in an output packet outputted from the output means. And a control signal output means for outputting the discontinuity detection signal generated by the reset means, wherein at least the recording start information is detected by the information detection means or by the ID detection means. 21. The magnetic reproducing apparatus according to claim 20, wherein when the frame information is discontinuous, an external or internal system indicates that there is a temporally discontinuous packet in an output packet output from the output unit. . 22. The output control means includes reference time stamp generating means for generating a reference time stamp for comparison with the detected time stamp detected by the time stamp detecting means, and the reset means includes at least the reset time stamp. By the information detection signal or the ID discontinuity signal,
22. The magnetic reproducing apparatus according to claim 20, wherein the reference time stamp generation unit is reset by initializing the reference time stamp generation unit with a detection time stamp detected by the time stamp detection unit.