JP2001177794A - Time stamp information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently record a program signal when it is recorded in a tape recording and reproducing means by which recording is performed by a data rate being higher than that of the program signal. SOLUTION: A TS packet encoding part 1 collects a plurality of time stamps for restoring the packet interval of each packet in the incoming program signal, stores them in a time stamp packet with a data amount being the same as that of each packet of the program signal and outputs them. A disk recording and reproducing part 3 and a tape recording and reproducing part 4 copy the program signal between the parts 3 and 4 by exceeding the data rate of the program signal when they copy it since recording and reproducing are possible in the time stamp packet in the same way as that of each packet of the program signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to processing of time stamp information added to a program signal transmitted in packet units.

[0002]

2. Description of the Related Art As a tape recording / reproducing apparatus for recording / reproducing an MPEG transport packet, a D-VHS (registered trademark) digital VTR for recording a bit stream of the MPEG transport packet is known. I have. This digital VTR has a feature that a large-capacity video / audio signal can be recorded using a removable tape recording medium, but it takes time for random access to the recorded video / audio signal.

On the other hand, in recent years, a disk recording / reproducing apparatus for a video / audio signal using an HDD has appeared, but the recording / reproducing apparatus using the HDD has a feature that random access of a recorded video / audio signal can be performed quickly. However, since the recording time of the video / audio signal is short and the recording medium is not removable, there is a disadvantage that the video / audio signal cannot be recorded beyond the recording time that can be recorded on the recording medium provided inside the apparatus.

[0004] Under such circumstances, the disk recording / reproducing apparatus is used for recording and reproducing video and audio signals on a daily basis.
The tape recording / reproducing apparatus is considered to be used for storing video / audio signals when the recording capacity of the disk recording / reproducing apparatus is insufficient.

[0005] In this case, for example, a time stamp for restoring each packet interval is added to each MPEG transport packet composed of 188 bytes of data received by a set-top box or the like, and the time stamp is restored by a disk recording / reproducing apparatus. When the recording capacity of the disc is insufficient, the packet is reproduced so that each packet interval is restored based on the time stamp at which a part of the video / audio signal recorded on the disc is recorded. The packet is recorded by the tape recording / reproducing device.

[0006]

However, as described above, when copying a video / audio signal from a disk recording / reproducing apparatus to a tape recording / reproducing apparatus, for example, it is necessary to copy one hour of a video / audio signal of a program. It took time, and it was not possible to efficiently copy the video and audio signals.

[0007]

According to a first aspect of the present invention, there is provided a time stamp information processing apparatus comprising a predetermined number of pieces of time stamp information for restoring a packet interval of each packet of a program signal transmitted in a packet unit of a fixed data amount. A time stamp packet encoding unit that collects and generates and outputs a time stamp packet having the same data amount as each of the packets; and a time stamp packet decoding unit that separates the predetermined number of pieces of time stamp information from the time stamp packets. It is characterized by the following.

[0008] In the time stamp information processing apparatus according to claim 2, the time stamp packet encoding means converts the predetermined number of packets in which time stamp information is stored in the time stamp packet into the time stamp packet. 2. The method according to claim 1, further comprising: outputting, at the beginning of the time stamp packet, identification information for identifying the time stamp packet from each of the packets and information indicating the predetermined number.
Is a time stamp information processing apparatus.

The time stamp information processing apparatus according to claim 3, when recording the program signal by a tape recording / reproducing means capable of performing recording / reproduction at a data rate higher than the data rate of the program signal, 3. The time stamp information processing apparatus according to claim 2, wherein the time stamp packet output from the time stamp packet encoding unit and each of the packets are recorded at a data recording rate higher than a data rate of the program signal. .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A time stamp information processing apparatus according to the present invention has a data rate which a program signal has when a program signal is copied from a disk recording / reproducing means connected to the inside or outside to a tape recording / reproducing means. It is characterized in that it can be copied at a higher data recording rate, and will be described in detail below.

FIG. 1 is a diagram for explaining a time stamp information processing apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a time stamp packet encoding unit (hereinafter, referred to as a TS packet encoding unit); A stamp packet decoding unit (hereinafter, referred to as a TS packet decoding unit); 3, a disk recording / reproducing unit using a hard disk as a recording medium;
Reference numeral 4 denotes a D-VHS tape recording / reproducing unit using a magnetic tape as a recording medium.

The TS packet encoding unit 1 receives MPEG transport packets constituting a program, and the TS packet encoding unit 1 adds a time stamp to each packet therein as described later, The stamp is stored in a 188-byte time stamp packet (hereinafter, referred to as a TS packet) and output to the disk recording / reproducing unit 3 together with the transport packet. Then, the disk recording / reproducing unit 3 records the transport packet and the TS packet from the TS packet encoding unit 1.

On the other hand, when reproducing the transport packet and the TS packet from the disk recording / reproducing unit 3, these packets are output to the TS packet decoding unit 2 and
The S packet decoding unit 2 outputs each transport packet while restoring the packet interval of the transport packet based on the TS packet.

If the recording capacity of the disc in the disc recording / reproducing unit 3 is insufficient, the transport packets and TS packets of the program recorded on the disc are copied to the tape recording / reproducing unit 4, and the copying is completed. A transport packet and a TS packet of a new program are recorded in the area on the disk. Since both the transport packet and the TS packet are composed of 188-byte data packets, the tape recording and reproducing unit 4 The port packet and the TS packet can be packet-recorded as they are.

The tape recording / reproducing unit 4 uses a magnetic head provided on a drum rotating at a predetermined rotation speed,
The incoming packets can be packet-recorded at a predetermined data recording rate because the incoming packets are recorded in a bit stream while forming inclined tracks on the magnetic tape run at a predetermined running speed. When the transport packet and the TS packet are reproduced from the tape, the data reproduction rate is made to coincide with the data recording rate of the tape recording / reproducing unit 4 so that the program can be copied in a shorter time than the actual time of the program. .

For example, the tape recording / reproducing unit 4 has a data recording rate of 14 Mbps, and a program copied from the disk recording / reproducing unit 3 to the tape recording / reproducing unit 4 is a real-time video / audio signal having a data rate of 7 Mbps and 60 minutes. , The disc recording / reproducing unit 3 to the tape recording / reproducing unit 4
You can copy this program in about 30 minutes. Similarly, when the program is copied from the tape recording / reproducing unit 4 to the disc recording / reproducing unit 3, it can be performed in about 30 minutes.

Next, the internal configuration of the TS packet encoding unit 1 will be described with reference to FIG. In the figure, 1a is a packet memory for sequentially storing incoming transport packets, and 1b is a T which generates a time stamp for restoring the packet interval of each transport packet.
The S generator 1c is a TS memory for sequentially storing the time stamps generated by the TS generator 1b.

1d counts the number of incoming transport packets, starts reading control of the packet memory 1a and the TS memory 1c at the timing when the number reaches a predetermined number, and simultaneously controls the selecting unit 1e. Further, a timing generation unit that outputs the counted value to the ID addition unit 1f, 1f
Is an ID adding unit that adds an ID to the head of the time stamp read from the TS memory 1c and outputs it as a TS packet. 1e is based on the control of the timing generating unit 1d.
A selection unit that outputs either a TS packet output from the D addition unit 1f or a transport packet output from the packet memory 1a.

FIG. 3 is a diagram for explaining the operation of the TS packet encoding unit 1. When a transport packet arrives as shown in FIG. 3A, the incoming transport packet is written into the packet memory 1a. And T
The S generator 1b generates a time stamp for restoring the packet interval of the incoming packet. Then, the time stamp generated by the TS generator 1b is written into the TS memory 1c. The timing generator 1d counts up an internal counter each time one transport packet arrives.

Such transport packet writing and time stamp writing are performed for each incoming transport packet. For example, six transport packets are written to the packet memory 1a by the count value in the timing generator 1d. At this timing, the timing generator 1d outputs a read start pulse to the TS memory 1c.

At this time, in the TS memory 1c, time stamps TS1 to TS1 corresponding to each packet shown in FIG.
S6 is written, and the TS memory 1c that has received the read start pulse from the timing generator 1d reads out all the time stamps TS1 to TS6 written therein.

Then, the ID adding unit 1f adds an ID to the head of the time stamps TS1 to TS6 read from the TS memory 1c, and then adds the ID to the time stamps TS1 to TS6 as shown in FIG.
Output as an 88-byte TS packet. At this time, an identifier (2 bytes) for distinguishing a transport packet from a TS packet and the number of time stamps in the TS packet (2 bytes) are added as shown in FIG.

As described above, since the data amount of the ID is 4 bytes and the data amount of each time stamp is 4 bytes, 188
A maximum of 46 time stamps can be stored in a byte TS packet. Here, the TS packet is composed of an ID, six time stamps, and dummy data.

[0024] The TS packet thus configured has an ID of ID.
The signal is output from the addition unit 1f, and at this time, the selection unit 1e receives the T from the ID addition unit 1f based on the control of the timing generation unit 1d.
Selectively output S packets. Then, when the TS packet is output, the timing generation unit 1d subsequently sets each of the transport packets 1 to 6 in the packet memory 1a.
Is read out, and a readout start pulse is output to the packet memory 1a so as to be output from the selection unit 1e, and the selection unit 1e is controlled.

As described above, as shown in FIG.
The packet and each transport packet are output from the TS packet encoding unit 1, and thereafter, similarly, a TS packet storing six time stamps and six transport packets storing time stamps in the TS packet are sequentially output. You. These buckets are recorded by the disk recording / reproducing unit 3 as described above.

FIG. 4 is a diagram for explaining the internal configuration of the TS packet decoding unit 2, and the disk recording / reproducing unit 3
The transport packet and the TS packet reproduced in step (1) come in. In the figure, reference numeral 2a denotes an ID discriminating unit for discriminating whether a packet is a transport packet or a TS packet based on a leading portion of each incoming packet, and 2b denotes a packet discriminating result of the ID discriminating unit 2a. The incoming packet is stored in the packet memory 2d based on the
Alternatively, it is a selection unit for selectively outputting to any one of the TS memories 2c.

[0027] Further, 2c is a TS memory for holding TS packets output from the selection unit 2b, 2d is a packet memory for sequentially holding transport packets output from the selection unit 2b, and 2e is an ID discrimination unit 2a. Based on the number of time stamps in the output TS packet and the packet interval information from the TS decoding unit 2f, the packet memories 2d and T
This is a timing generator for controlling the S memory 2c. A TS decoding unit 2f generates packet interval information based on the time stamp output from the TS memory 2c.

When a transport packet and a TS packet arrive in the TS packet decoding unit 2 configured as described above, the ID discriminating unit 2a determines whether the packet is a transport packet based on the head of each packet. Is determined, and the selector 2b is controlled so that the transport packet is written in the packet memory 2d and the TS packet is written in the TS memory 2c. If the incoming packet is a TS packet,
The number of time stamps stored in the TS packet is output from the ID determination unit 2a to the timing generation unit 2e.

When all the six transport packets shown in FIG. 3C are written to the packet memory 2d, the timing generator 2e outputs a read start pulse to the TS memory 2c, and the TS memory 2c Are sequentially output to the TS decoding unit 2f. TS
The decoding unit 2f generates packet interval information based on the time stamp, and outputs this to the timing generation unit 2e.

[0030] Then, the timing generator 2e, based on the packet interval information from the TS decoder 2f, stores the packet memory 2d.
Is read from the TS packet decoder 2, and the TS packet decoding unit 2 outputs the transport packet with the packet interval restored.

As described above, in the time stamp information processing apparatus according to the present invention, a plurality of time stamps added to each transport packet are collected and stored in a TS packet having the same data size as the transport packet.
Since this can be recorded and reproduced in the same manner as the transport packet, when the tape recording and reproducing unit 4 records this TS packet, it can be recorded in the same manner as the transport packet.

Therefore, when the tape recording / reproducing means is used for storing the video / audio signal, not only can the time for copying the video / audio signal from the disk recording / reproducing section 3 to the tape recording / reproducing section 4 be shortened, but also the tape The amount of magnetic tape used in the recording / reproducing unit can be reduced, and video / audio signals can be stored very efficiently.

In the embodiment described above, an example is shown in which a TS packet is generated by the TS packet encoding unit 1 and then recorded by the disk recording / reproducing unit 3 together with a transport packet, as shown in FIG. , A TS packet encoding unit may be provided between the disk recording and reproducing unit and the tape recording and reproducing unit.

[0034] As shown in FIG.
When the S-packet decoding unit is provided between the disk recording / reproducing unit and the tape recording / reproducing unit, a time stamp is added to each transport packet when recording a transport packet in disk recording / reproducing. When copying a program recorded on the disc recording / reproducing unit 7 to the tape recording / reproducing unit 4, the disc recording / reproducing unit 7
, A time stamp is output together with each transport packet, and the TS packet encoding unit 5 packetizes the time stamp output from the disk recording / reproducing unit 7.

FIG. 6 is a diagram for explaining the internal configuration of the TS packet encoding unit 5. In the figure, reference numeral 5a denotes a TS determination unit for determining a time stamp portion in a time-stamped transport packet, and 5b denotes T
Based on the information from the S discriminator 5a, the selector outputs the time stamp portion of the incoming transport packet with the time stamp to the TS memory 5c and outputs the transport packet portion to the packet memory 5d. .

Reference numeral 5c denotes a TS memory for sequentially holding the time stamp output from the selection unit 5b, and 5d denotes a selection unit 5b.
5e sequentially counts the number of incoming transport packets, and starts reading control of the packet memory 5d and the TS memory 5c when the number reaches a predetermined number. At the same time, it is a timing generation section that controls the selection section 5f and outputs the value obtained by the coefficient to the ID addition section 5g.

An ID adding unit 5g adds an ID to the head of the time stamp read from the TS memory 5c and outputs the packet as a TS packet. 5f denotes a timing generating unit 5e.
Is a selection unit that outputs either the TS packet output from the ID addition unit 5g or the output transport packet from the packet memory 5d based on the control of.

When a transport packet with a time stamp is input to the TS packet encoding unit 5 configured as described above, the TS discriminating unit 5a discriminates the time stamp part, and controls the selecting unit 5b to determine the time. The stamp is written in the TS memory 5c and the transport packet is written in 5d. The timing generator 5e counts up its internal counter each time one transport packet arrives.

The above-described processing is performed for each incoming transport packet. For example, at the timing when six transport packets are written in the packet memory 5d based on the count value in the timing generator 5e, the timing generator 5e A read start pulse is output to the TS memory 5c. Then, the ID adding unit 5g adds an ID to the head of the time stamp read from the TS memory 5c, and outputs this as a 188-byte TS packet.

When such a TS packet is output from the ID adding unit 5g, the selecting unit 5f selects and outputs the TS packet from the ID adding unit 5g under the control of the timing generating unit 5e. Then, when the TS packet is output, the timing generator 5e reads out each transport packet in the packet memory 5d subsequently, and outputs a read start pulse to the packet memory 5d so that the transport packet is output from the selector 5f. Output and controls the selection unit 5f.

As described above, as shown in FIG.
The S packet and each transport packet are output from the TS packet encoding unit 1 and recorded by the tape recording / reproducing unit 4.

On the other hand, FIG. 7 is a diagram for explaining the internal configuration of the TS packet decoding unit 6, in which the TS packets reproduced by the tape recording / reproducing unit 4 and each transport packet are received. In the figure, reference numeral 6a denotes an ID discriminating unit for discriminating whether a packet is a transport packet or a TS packet based on a leading portion of each incoming packet, and 6b denotes a packet discriminating result of the ID discriminating unit 6a. Packet memory 6d based on incoming packets
Alternatively, it is a selection unit for selectively outputting to any one of the TS memories 6c.

Further, 6c is a TS memory for holding TS packets output from the selection unit 6b, 6d is a packet memory for sequentially holding transport packets output from the selection unit 6b, and 6e is an ID discrimination unit 6a. The packet memory 6d and the TS memory 6c are controlled based on the number of timestamps in the TS packet to be output, and the selection unit 6f
Is a timing generator for controlling the timing. 6f is a packet memory 6d based on the control of the timing generator 6e.
This is a selector that performs a switching operation to output a time stamp from the TS memory 6c corresponding to the transport packet immediately before the transport packet output from.

When the TS packet and the transport packet arrive in the TS packet decoding unit 6 configured as described above, the ID discriminating unit 6a determines whether the packet is a transport packet according to the head of each packet. Is determined, and the selector 6b is controlled so that the transport packet is written in the packet memory 6d and the TS packet is written in the TS memory 6c. If the incoming packet is a TS packet,
The number of time stamps stored in the TS packet is output from the ID determination unit 6a to the timing generation unit 6e.

Then, the ID discriminating section 6a is connected to the timing generating section 6
When all the transport packets of the number of timestamps output to e are written to the packet memory 6d, the timing generator 6e outputs a read start pulse to the TS memory 6c and then outputs a read start pulse to the packet memory 6d. 6f switches the input so that the transport packet from the packet memory 6d is output immediately after the time stamp output from the TS memory 6c under the control of the timing generator 6e.

The timing generator 6e repeats the above operation by the number of transport packets held in the packet memory 6d, and outputs all transport packets together with a time stamp to the disk recording / reproducing unit 7, and The recording / reproducing unit 4 records the time stamp and the transport packet from the TS packet decoding unit 6.

As described above, the time stamp is packetized before recording the program in the disk recording / reproducing unit 3, and is recorded in the disk recording / reproducing unit 3. Thereafter, the program is transmitted together with the packetized time stamp. Even when recording is performed by the tape recording / reproducing unit 4, or when the time stamp reproduced from the disk recording / reproducing unit 7 is packetized and then recorded by the tape recording / reproducing unit 4, the copy time is reduced and the magnetic time is reduced. Tape usage can be reduced.

In the above embodiment, a hard disk drive is used as the disk recording / reproducing unit 2. However, if a recording / reproducing apparatus capable of reproducing at a variable data rate is used, for example, a semiconductor memory or the like may be used. You can use it.

[0049]

According to the present invention, since the time stamp information to be added to each packet is stored in the time stamp packet having the same data amount as the packet forming the program signal, the signal is recorded and reproduced in packet units. In the tape recording / reproducing means, there is an effect that the time stamp packet can be recorded / reproduced in the same manner as the packet forming the program signal.

[0050] Also, since identification information for identifying a packet constituting a program signal is stored at the head of the time stamp packet, the time stamp information is separated from the time stamp packet using this identification information. Becomes possible.

When a program signal is recorded by the tape recording / reproducing means capable of recording / reproducing at a data rate higher than the data rate of the program signal, the tape recording / reproducing means uses a data rate higher than the data rate of the program. Therefore, the recording time of the program signal can be reduced, and the amount of use of the magnetic tape can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a time stamp information processing apparatus according to the present invention.

FIG. 2 is a diagram illustrating an example of a configuration of a TS packet encoding unit.

FIG. 3 is a diagram for explaining the operation of a TS packet encoding unit.

FIG. 4 is a diagram illustrating an example of a configuration of a TS packet decoding unit.

FIG. 5 is a block diagram for explaining another embodiment of the time stamp information processing apparatus according to the present invention.

FIG. 6 is a diagram illustrating another configuration of the TS packet encoding unit.

FIG. 7 is a diagram illustrating another configuration of the TS packet decoding unit.

[Explanation of symbols]

 1, 5... TS packet encoder 1a, 2d, 5d, 6d... Packet memory 1b... Time stamp generator 1c, 2c, 5c, 6c... Time stamp memory 1d, 2e, 5e, 6e. 5b, 5f, 6b, 6f: selecting unit 1f, 5g: ID adding unit 2a, 6a: ID discriminating unit 2f: time stamp decoding unit

Claims (3)

[Claims] 1. A method for collecting a predetermined number of time stamp information for restoring a packet interval of each packet of a program signal transmitted in a packet unit of a fixed data amount, and generating a time stamp packet having the same data amount as each packet. A time stamp information processing apparatus comprising: a time stamp packet encoding means for outputting; and a time stamp packet decoding means for separating the predetermined number of pieces of time stamp information from the time stamp packets. 2. The time stamp packet encoding unit outputs the predetermined number of packets in which time stamp information is stored in the time stamp packet, following the time stamp packet, and outputs the packet at the beginning of the time stamp packet. The time stamp information processing apparatus according to claim 1, wherein identification information for identifying the time stamp packet from each of the packets and information indicating the predetermined number are stored. When recording the program signal by a tape recording / reproducing means capable of recording and reproducing at a data rate higher than the data rate of the program signal, the time stamp output by the time stamp packet encoding means 3. The time stamp information processing apparatus according to claim 2, wherein a packet and each of the packets are recorded at a data recording rate higher than a data rate of the program signal.