JP3774579B2 - AV bitstream recording / playback system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a time stamp giving system for giving a time stamp to packet data constituting an AV bit stream.With, AV bit stream recorded on a predetermined recording mediumRecordAV bit stream to playRecordPlayback systemInIt is related.
[0002]
[Prior art]
Conventionally, when an AV bit stream of a packet in which video and / or audio data is packetized according to, for example, the MPEG2 standard is recorded on a recording medium such as a magnetic tape using a recording device, the recording device has 27 MHz ± A unique vibrator that vibrates according to a frequency satisfying 30 ppm is provided in advance, and a time stamp indicating the reproduction timing of each packet is given to all or some of the packets using the vibration of the vibrator as a reference clock for recording. The method of doing is known.
[0003]
In addition, when the AV bit stream described above is recorded on a recording medium using an interface corresponding to IEEE 1394 in the transmission path of the AV bit stream, a time stamp indicating the reproduction timing of each packet using an interface-specific reference clock There is also known a method of recording by assigning to a corresponding packet.
[0004]
On the other hand, when reproducing the AV bit stream recorded on the recording medium in such a manner using a reproducing apparatus, the reproducing apparatus is previously provided with a unique vibrator that vibrates in accordance with a frequency satisfying 27 MHz ± 30 ppm. There is also known a method of reproducing each packet by using a time stamp given to the packet using the vibration of the vibrator as a reference clock.
[0005]
By the way, unlike what was mentioned above, for example, when a long drama of 10 hours is broadcast and it is going to record it, since recording time is long, it is difficult to record all on one magnetic tape. Therefore, when it is necessary to record a program for a long time, for example, two recording devices are prepared, and the first half of the program is recorded on a separate recording medium in each recording device so that overlapping scenes are generated. The second half will be recorded. When playing back programs recorded in this way, the first half is first played back and output, the first half and the second half are connected using the scenes recorded in duplicate, and the second half It is necessary to switch to playback so that is output. Further, not only when recording a program for a long time as described above, but also when the remaining recordable capacity of the recording medium is smaller than the capacity corresponding to the entire length of the program to be recorded, etc. A plurality of recording devices may be prepared, and the program may be divided and recorded so that a scene that is recorded redundantly occurs. In any case, when a program is divided and recorded on a plurality of recording media and played back, the divided ones are connected using the recorded scenes and the output is switched. Will play.
[0006]
Further, unlike the above-described two conventional examples, for example, when an AV bit stream according to the MPEG2 standard from a broadcasting station is recorded on a recording medium such as a magnetic tape using a recording device, the AV bit stream is directly recorded on the recording medium. There is known a method of temporarily storing digital data in a semiconductor RAM capable of recording without recording the data, outputting an AV bit stream from the semiconductor RAM, and recording the AV bit stream on a recording medium. Also, when reproducing and outputting an AV bit stream recorded on a recording medium such as a magnetic tape, the AV bit stream from the recording medium is temporarily output to the semiconductor RAM without being directly output, and the semiconductor RAM A method of outputting an AV bit stream is also known.
[0007]
[Problems to be solved by the invention]
  However, in the first conventional example described above, that is, when an AV bit stream composed of a large number of packets is recorded on a recording medium with a time stamp added to the packet using a reference clock specific to the recording apparatus or interface. Since the reference clock is different for each recording device or for each interface, the reproduction timing of each packet is different even for the same AV bit stream. In other words, even with the same packet, time stamps having different reproduction timings are given. When reproducing the AV bit stream recorded on the recording medium in this way, the AV bit stream is reproduced using the time stamp given to each packet based on the reference clock unique to the reproduction apparatus. Unless the reference clock at the time of reproduction and the reference clock at the time of recording are substantially the same, each packet of the AV bit stream cannot be reproduced at substantially the same timing as at the time of recording. For example, in an AV bit stream according to the MPEG2 standard, it is determined that the AV bit stream is recorded or reproduced using the vibration of the vibrator oscillating according to a frequency satisfying 27 MHz ± 30 ppm as a reference clock, and exceeds the allowable range. When the AV bit stream recorded or reproduced using the vibration of the vibrator that vibrates according to the frequency as a reference clock is displayed on the monitor, there are many problems such as an image being disturbed. Therefore, when the reference clock at the time of reproduction and the reference clock at the time of recording are not substantially the same, both the reference clock at the time of recording and the reproduction are based on the vibration of the vibrator that vibrates according to the frequency satisfying 27 MHz ± 30 ppm. Even if it is a clock, the deviation of the reference clock at the time of recording is accumulated at the time of reproduction, so that each packet of the AV bit stream is reproduced using the vibration of the vibrator that vibrates according to the frequency satisfying 27 MHz ± 30 ppm as the reference clock. May not be possible. In addition, if the AV bit stream from the broadcasting station is recorded once and reproduced, the problem is that the image when the AV bit stream is displayed on the monitor is disturbed if substantially the same reference clock is used during recording and reproduction. However, if the recorded bit is reproduced and the AV bit stream is recorded on the recording medium using another recording device, the reference clock is different for each recording device and each reproducing device. , The deviation of the reference clock is accumulated and assigned to each packet of the AV bitstream.MuFor example, the stamp is not generated using the vibration of the vibrator that vibrates according to the frequency satisfying the allowable range of 27 MHz ± 30 ppm as a reference clock. As described above, when an AV bit stream is recorded or reproduced using a unique reference clock for each recording device, each interface, or each reproduction device, the AV bit stream is repeatedly recorded or repeatedly transferred. At the same time, deviations of the reference clock are accumulated and assigned to each packet of the AV bitstream.MuThe stamp is not generated using the vibration of the vibrator that vibrates according to the frequency satisfying the allowable range as a reference clock.
[0008]
Therefore, the present invention generates a substantially fixed reference clock based on time information recorded in advance in the AV bitstream, generates a time stamp according to the substantially fixed reference clock, and assigns it to each packet. The object is to provide a time stamping system. It is another object of the present invention to provide an AV bit stream reproduction system that reproduces each packet to which a time stamp is attached in accordance with the substantially fixed reference clock described above.
[0009]
By the way, unlike the above-described first conventional example, in the case of the second conventional example in which a certain program is divided and recorded on a plurality of recording media and reproduced, the scenes recorded in duplicate are reproduced. However, when the connection is displayed on the monitor, the image near the connection is disturbed. In order to solve the disturbance, it is conceivable to record each scene with a unique number added to each scene, and connect using that number during playback. If the AV data to be recorded is AV data in which each frame unit is not specified, for example, MPEG2-TS (Transport Stream), a scene recorded in duplicate cannot be specified. When displaying a nearby image, the image is disturbed. That is, in the conventional recording apparatus, for example, MPEG2-TS described above is not defined as a scene but for each predetermined unit such as a packet constituting MPEG2-TS, and the unit is clearly defined on a recording medium such as a magnetic tape. Since it cannot be recorded, it cannot be specified which unit and which unit should be connected when reproducing.
[0010]
  Therefore, the present inventionInventions related toConventionally, when an AV bitstream whose scene is not specified is divided and recorded on a plurality of recording media so as to generate an overlapping portion and reproduced, it cannot be accurately connected and reproduced. In consideration of the AV bit stream in which the scene is not specified, an AV bit stream recording system for recording the AV bit stream so that the AV bit stream can be accurately connected at the time of reproduction, and the AV bit stream is accurately connected. An object of the present invention is to provide an AV bit stream playback system for playback.
[0011]
Further, unlike the above-described two conventional examples, when the AV bit stream is temporarily stored in the semiconductor RAM when the AV bit stream is recorded or reproduced, the semiconductor RAM has a small capacity and capability. Cannot be played back and output in the order in which they were stored. By increasing the scale of the semiconductor RAM, it is possible to accumulate a large amount of data and to reproduce it quickly in the order of accumulation, but in that case, the scale of the recording device or the reproducing device increases.
[0012]
  Therefore, the present inventionInventions related toConsidering the problem that conventional recording devices and playback devices temporarily store a large amount of data, and cannot quickly reproduce and output the stored data in the order in which they were stored, temporarily store a large amount of data, It is an object of the present invention to provide an AV bit stream reproduction system and an AV bit stream recording system that can quickly reproduce and output the accumulated data in the order of accumulation.
[0013]
[Means for Solving the Problems]
  According to a first aspect of the present invention (corresponding to claim 1), there is provided a packetized packet stream including video and / or audio data.LeaveThe time information indicating the playback timing isStoreAn input means for inputting the AV bit stream being processed;
  The time information of the AV bit stream input by the input means isStoreBased on a plurality of said time information of the packet beingAn oscillating means for oscillating a timing control signal whose oscillation period is controlled;
  A time for generating a reference clock using the timing control signal of the oscillating means and generating a time stamp indicating the reproduction timing of each packet of all the packets or at least all the packets in which the time information is not stored A stamp generating means;
  Time stamp giving means for giving the time stamp generated by the time stamp generating means to each packet corresponding to the time stamp;,
  HaveTime stamping systemIn addition,
Temporary storage means for inputting, temporarily storing and outputting the AV bit stream output from the time stamp assigning system in units of packets in order from the top of the AV bit stream;
  The output timing of the packet output from the temporary storage means is determined based on the time stamp given to all or part of the packets of the AV bitstream, and the timing control signal oscillated by the oscillation means is used. Control means for controlling to output from the temporary storage means in synchronization with the generated reference clock;
AV bit stream recording / playback system characterized by comprisingIt is.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0019]
  (Embodiment 1)
  First, the configuration of the time stamp assigning system and the AV bit stream reproduction system according to the first embodiment of the present invention will be described.The AV bit stream recording / reproducing system of the present invention is composed of a time stamp assigning system and an AV bit stream reproducing system described below.
[0020]
FIG. 1 shows a block diagram of a time stamp assigning system and an AV bit stream reproduction system according to Embodiment 1 of the present invention.
[0021]
The time stamp assigning system according to the first embodiment of the present invention includes an input unit 1, a time stamp generating unit 2, and a time stamp assigning unit 3. The time stamp generating means 2 includes a PCR extracting means 4, a counter 5, a difference calculating means 6, a filter means 7, and a VCO (Voltage Controlled Oscillator) 8.
[0022]
On the other hand, the AV bitstream reproduction system according to the first embodiment of the present invention includes a FIFO 9, a FIFO management unit 10, a time stamp extraction unit 11, a second counter 12, a first stamp memory 13, and a second stamp memory. 14, a stamp value difference calculating unit 15, a counter memory 16, a counter value difference calculating unit 17, and a difference comparing unit 18.
[0023]
In FIG. 1, storage means 19 and output means 20 are also displayed.
[0024]
The input means 1 is a means for inputting an AV bit stream from a broadcasting station according to the MPEG2 standard. The AV bit stream is composed of a large number of packets in which video and / or audio data is packetized. In a plurality of predetermined packets among the many packets, a PCR (Program Clock Reference, reference time signal) as time information indicating the reproduction timing of the predetermined plurality of packets is recorded. The PCR is recorded in the AV bit stream packet so that at least one exists in about 100 ms, and the vibration of the vibrator that vibrates according to a high-precision frequency of 27 MHz ± 3 ppm is used as a reference clock. It will be recorded. However, PCR is not expressed in units of date, minute, and second, but is information on the value obtained by counting the number of vibrations of the vibrator, and can generally be handled as equivalent to absolute time. It is. Further, PCR recording may be performed periodically, for example, every 50 ms, or may not be performed periodically. In short, the PCR only needs to be recorded in the AV bit stream packet so that at least one PCR exists in about 100 ms. Normally, an MPEG2 AV bitstream includes various tables and packets in which program information is packetized in addition to video and audio data packets. As shown in FIG. 2A, the AV bit stream is composed of a large number of packets in which only video data is packetized, and the PCR is periodically recorded in packets at intervals of 100 ms. Suppose that In FIG. 2, packets in which PCRs are recorded are indicated by diagonal lines, and in order to distinguish a plurality of PCRs, each PCR is designated as a first PCR, a second PCR, a third PCR,... In order from the beginning of the AV bitstream. , The first PCR, the second PCR, the third PCR,... Are recorded as the first PCR, the second PCR, the third PCR,.
[0025]
The time stamp generating means 2 detects the packet in which the PCR is recorded in the AV bit stream input by the input means 1 and extracts the PCR. Based on the plurality of PCRs, the reproduction timing of each of all the packets Is a means for generating a time stamp indicating. As described above, the time stamp generating unit 2 includes the PCR extracting unit 4, the counter 5, the difference calculating unit 6, the filter unit 7, and the VCO 8. The elements will be described later when the operation of the time stamp assigning system according to the first embodiment of the present invention is described.
[0026]
The time stamp giving means 3 is a means for giving the time stamp generated by the time stamp generating means 2 to each packet corresponding to the time stamp.
[0027]
Next, the storage unit 19 is an HDD (Hard Disk Drive) that stores the AV bit stream to which the time stamp is added by the time stamp adding unit 3. The FIFO 9 is a means for inputting and temporarily storing the AV bit stream stored in the storage means 19 for each packet and outputting it for each packet in accordance with an instruction from the difference comparison means 18.
[0028]
The FIFO management unit 10 is a unit that controls the storage unit 19 to input the AV bit stream stored in the storage unit 19 to the FIFO 9 for each packet in order from the head of the AV bit stream.
[0029]
The time stamp extraction unit 11 is a unit that extracts a time stamp given to each packet input from the storage unit 19 to the FIFO 9.
[0030]
The second counter 12 is means for counting a predetermined value based on a timing control signal from the VCO 8 of the time stamp generating means 2. The timing control signal will be described later.
[0031]
The first stamp memory 13 and the second stamp memory 14 are means for temporarily recording the time stamp extracted by the time stamp extracting means 11.
[0032]
The stamp value difference calculation means 15 is a means for calculating a difference between time stamp values recorded in the first stamp memory 13 and the second stamp memory 14.
[0033]
The counter memory 16 is means for temporarily recording the value of the second counter 12 in accordance with an instruction signal from the difference comparison means 18.
[0034]
The counter value difference calculation means 17 is a means for calculating a difference between the value recorded in the counter memory 16 and the value of the second counter 12.
[0035]
The difference comparison means 18 compares the difference calculated by the stamp value difference calculation means 15 with the difference calculated by the counter value difference calculation means 17 and sends a predetermined packet from the FIFO 9 at a timing when both substantially coincide. This is a means for controlling to output the value and to record the value of the second counter 12 at the timing described above in the counter memory 16.
[0036]
The output unit 20 is a unit that outputs a packet from the FIFO 9.
[0037]
  It should be noted that the present invention of claim 1AV bitstream recording and playbackIn the system, input means 1 as input means, time stamp generation means 2 as time stamp generation means, and time stamp assignment means 3 as time stamp assignment meansVCO8 as oscillation means, FIFO9 as temporary storage meansWas used. Also,As a control means,Time stamp extraction means 11,First2 counter 12,A first stamp memory 13, a second stamp memory 14, a stamp value difference calculating means 15, a counter memory 16, a counter value difference calculating means 17,Difference comparison means 18 was used.
[0038]
Next, operations of the time stamp assigning system and the AV bitstream reproduction system according to Embodiment 1 of the present invention will be described.
[0039]
First, the operation of the time stamping system will be described.
[0040]
First, the input means 1 inputs an AV bit stream from the broadcasting station shown in FIG.
[0041]
Next, the time stamp generation means 2 detects the packet in which the PCR is recorded in the AV bit stream input by the input means 1 and extracts the PCR. Actually, the PCR extraction means 4 extracts the PCR. In order to distinguish a plurality of PCRs as described above, each PCR is designated as a first PCR, a second PCR, a third PCR,... In order from the head of the AV bitstream.
[0042]
When the PCR is first extracted, the PCR extraction unit 4 sets the same value as the value of the first PCR in the counter 5 at substantially the same timing as the extraction of the first PCR. Here, for convenience of the following description, the value of the first PCR is assumed to be “0”, and the value of “0” is set in the counter 5 at the same timing as the timing at which the first PCR is extracted by the PCR extracting means 4. And The counter 5 counts one by one based on the timing control signal from the VCO 8 and outputs the count value (integrated value) to the difference calculating means 6 and the time stamp giving means 3. The VCO 8 has a vibrator that vibrates in accordance with a frequency in the vicinity of 27 MHz, and oscillates a timing control signal each time the vibrator vibrates once.
[0043]
When the time stamp giving means 3 inputs the count value from the counter 5, every time the count value is inputted, the header of each packet of the AV bit stream transmitted from the input means 1 at the input timing, As shown in black in FIG. 2B, the count value from the counter 5 is given as a time stamp and output. Then, the packet from the time stamp assigning means 3 is accumulated in the accumulating means 19.
[0044]
By the way, the VCO 8 oscillates a timing control signal in the vicinity of 27 MHz, that is, based on a frequency different from the above-mentioned 27 MHz ± 3 ppm. Therefore, at the same timing as the timing at which the first PCR is extracted by the PCR extracting means 4, Even if a value of “0” is set to “0”, the integrated value of the counter 5 is counted based on a reference clock according to a highly accurate frequency of 27 MHz ± 3 ppm obtained from the AV bit stream input by the input means 1. Will deviate from this value.
[0045]
Therefore, in order to make the integrated value of the counter 5 substantially coincide with the count value based on the reference clock according to the highly accurate frequency of 27 MHz ± 3 ppm obtained from the AV bit stream input by the input means 1, the following operation is performed. Do.
[0046]
First, the PCR extracting means 4 detects a PCR next to a packet in which the first PCR is recorded, that is, a packet in which the second PCR is recorded, and extracts the second PCR. As described above, in the first embodiment, for convenience of explanation, since the PCR is periodically recorded in the packet at 100 ms intervals, the value of the second PCR is “27000”. Then, the PCR extraction unit 4 outputs the extracted second PCR value “27000” to the difference calculation unit 6. Next, the difference calculating means 6 inputs the second PCR value “27000” from the PCR extracting means 4 and also inputs the count value (integrated value) from the counter 5 and calculates the difference between the two. Thereafter, the filter means 7 controls the voltage of the VCO 8 so that the difference becomes 0 (zero). That is, the oscillation period of the timing control signal that the VCO 8 oscillates is controlled. More specifically, the vibration frequency of the vibrator included in the VCO 8 is controlled. For example, if the count value (integrated value) of the counter 5 is “27010”, the difference obtained by subtracting the second PCR value “27000” from the PCR extracting means 4 from the count value of the counter 5 is “+10”. For example, if the count value (integrated value) of the counter 5 is “26990”, the difference is “−10”, so that the vibration frequency of the vibrator of the VCO 8 is advanced. The filter means 7 controls the voltage of the VCO 8.
[0047]
Thus, since the filter means 7 controls the period in which the VCO 8 oscillates the timing control signal, the integrated value of the counter 5 has a highly accurate frequency of 27 MHz ± 3 ppm obtained from the AV bit stream input by the input means 1. Accordingly, the count value based on the reference clock is substantially matched. That is, the time stamp given by the time stamp giving means 3 is generated and given so as to indicate the timing determined by the broadcasting station and substantially matching the timing at which each packet should be reproduced. .
[0048]
As described above, each PCR after the third PCR and each PCR are extracted so that the VCO 8 is controlled so that the second PCR and the value of the counter 5 when the second PCR is extracted are substantially equal. When the value of the counter 5 is controlled by controlling the VCO 8 so that the value of the counter 5 at that time is substantially equal, all the time stamps given by the time stamp giving means 3 are determined by the broadcasting station. Each packet is generated and assigned to indicate a timing that substantially matches the timing at which each packet is to be reproduced. That is, the time stamp is generated and given using the vibration of the vibrator that vibrates according to a high-accuracy frequency of 27 MHz ± 3 ppm obtained from the AV bit stream from the broadcasting station input by the input means 1 as a reference clock.
[0049]
Next, the operation of the AV bit stream playback system will be described.
First, the FIFO management means 10 controls the storage means 19 so that a predetermined number of FIFO bits of packets of the AV bit stream stored in the storage means 19 are sequentially received from the head of the AV bit stream. To input. Then, the FIFO 9 inputs the packet from the storage means 19 for each packet and temporarily stores it.
[0050]
At that time, the time stamp extraction means 11 extracts the time stamp given to each packet input from the storage means 19 to the FIFO 9. Here, for convenience of the following description, the packets input from the storage means 19 to the FIFO 9 are designated as the first packet, the second packet, the third packet,..., And the first packet, the second packet,. The time stamps assigned to the third packet,... Are the first time stamp, the second time stamp, the third time stamp,. At this time, first, the time stamp extracting means 11 extracts the first time stamp from the first packet and extracts the second time stamp from the second packet. Then, the time stamp extracting means 11 temporarily records the first time stamp in the first stamp memory 13 and the second time stamp in the second stamp memory 14 respectively.
[0051]
Then, the stamp value difference calculating means 15 calculates the difference between the value of the first time stamp recorded in the first stamp memory 13 and the value of the second time stamp recorded in the second stamp memory 14. .
[0052]
On the other hand, the second counter 12 counts one by one based on the timing control signal from the VCO 8 of the time stamp generating means 2. That is, it counts like the counter 5 of the time stamp generating means 2. When the first packet is output from the FIFO 9 to the output unit 20 at a predetermined timing, the second counter 12 temporarily records the count value of the output timing in the counter memory 16.
[0053]
Thereafter, the counter value difference calculating means 17 calculates the difference between the value recorded in the counter memory 16 and the real time value of the second counter 12, and the difference comparing means 18 is calculated by the counter value difference calculating means 17. The difference calculated and the difference calculated by the stamp value difference calculation means 15 are compared, and the second packet is output from the FIFO 9 to the output means 20 at the timing when the former substantially matches the latter. At the same time, the count value at the timing when the difference between the former and the latter substantially coincides is recorded from the second counter 12 to the counter memory 16. Further, the difference comparison means 18 causes the first stamp memory 13 to input the third time stamp from the third packet extracted by the time stamp extraction means 11.
[0054]
Then, the stamp value difference calculation means 15 calculates the difference between the value of the third time stamp recorded in the first stamp memory 13 and the value of the second time stamp recorded in the second stamp memory 14. The counter value difference calculating means 17 calculates the difference between the value recorded in the counter memory 16 and the real time value of the second counter 12, and the difference comparing means 18 is calculated by the counter value difference calculating means 17. And the difference calculated by the stamp value difference calculating means 15 are compared, and the third packet is output from the FIFO 9 to the output means 20 at the timing when the former substantially matches the latter. At the same time, the count value at the timing when the difference between the former and the latter substantially coincides is recorded from the second counter 12 to the counter memory 16. Further, the difference comparison unit 18 causes the second stamp memory 14 to input the fourth time stamp from the fourth packet extracted by the time stamp extraction unit 11.
[0055]
Similarly, the FIFO 9 causes the output means 20 to output packets one by one.
[0056]
In this way, the vibration of the vibrator that vibrates according to the reference clock based on the timing control signal from the VCO 8 of the time stamp generating means 2, that is, the high-accuracy frequency of 27 MHz ± 3 ppm obtained from the AV bit stream from the broadcasting station. Each packet is regenerated using a time stamp given to each packet as a reference clock.
[0057]
By the way, when the FIFO 9 outputs one packet to the output unit 20, the information to that effect is output to the FIFO management unit 10, and when the FIFO management unit 10 inputs the information, the FIFO 9 excludes what has already been input to the FIFO 9. Thus, one packet from the storage means 19 is input to the FIFO 9 in order from the beginning of the AV bitstream.
[0058]
In the first embodiment described above, as shown in FIG. 1, the second counter 12 counts based on the timing control signal from the VCO 8 of the time stamp generating means 2, but as shown in FIG. As an alternative to the second counter 12 of FIG. 1, a third counter 21 having a unique vibrator may be provided, and the third counter 21 may count according to a reference clock based on the vibration of the vibrator. Then, the packet may be output from the FIFO 9 to the output means 20 using the count value.
[0059]
In the first embodiment described above, the time stamp assigning system assigns a time stamp to all packets including packet data in which PCR is recorded when giving a time stamp to each packet of the AV bit stream from the broadcasting station. However, a time stamp may not be assigned to a packet in which a PCR is recorded.
[0060]
In the first embodiment described above, the time stamp assigning system uses PCR to assign each packet of the AV bit stream from the broadcast station in order from the first packet data. The time stamp in which the count value is integrated is added to the time stamp. However, the time stamp may be information on the difference between the count value of the packet to which the time stamp is to be added and, for example, the previous packet. . Alternatively, the time stamp may be relative information corresponding to a time interval at the time of reproduction between a packet to which the time stamp is to be assigned and, for example, the previous packet. In short, the time stamp only needs to be information indicating the reproduction timing when each packet is reproduced.
[0061]
  Furthermore, in the first embodiment described above, when reproducing the AV bit stream recorded in the storage means 19, the time stamp extraction means 11 extracts the time stamp from each packet, and the first stamp memory 13 or the second stamp Although each memory 14 is temporarily recorded, a register capable of recording a time stamp may be used instead of the first stamp memory 13 or the second stamp memory 14. At that time, a two-stage register is used so as to correspond to the first stamp memory 13 and the second stamp memory 14.
  In the first embodiment described above, the second counter 12 operates based on the timing control signal from the VCO 8, but may not operate based on the timing control signal. That is, the operation may be performed based on a unique reference clock. Further, when the AV bit stream input by the input means 1 is an AV bit stream using a reference clock having a period exceeding an allowable range such as 27 MHz ± 30 ppm, the second counter 12 receives the timing from the VCO 8. Disable operation based on the control signal. That is, the operation is performed based on a specific reference clock.
[0062]
  (Embodiment 2)
  Next, the present inventionInventions related toThe configurations of the AV bit stream recording system and the AV bit stream reproduction system according to the second embodiment will be described.
[0063]
  In FIG.FruitFIG. 4 shows a block diagram of an AV bit stream recording system and an AV bit stream reproduction system according to the second embodiment.
[0064]
  FruitThe AV bit stream recording system according to the second embodiment includes an input unit 22, a divided storage unit 23, an HDD (Hard Disk Drive) 24, and a tape recording device 25.
[0065]
  On the other handFruitThe AV bit stream playback system according to the second embodiment includes an HDD 24, a tape recording device 25, and connection means 26. The connection unit 26 includes a first semiconductor buffer 27, a second semiconductor buffer 28, and a connection control unit 29.
[0066]
The input means 22 is means for inputting an AV bit stream according to the MPEG2 standard. As described in the first embodiment, the AV bit stream is composed of a large number of packets in which video data is packetized, and a plurality of packets have PCR as time information indicating reproduction timing. Suppose that it is recorded. For convenience of explanation, it is assumed that the PCR is recorded in the first packet of the AV bit stream and each tenth packet from the packet as shown in FIG. That is, it is assumed that the PCR is recorded in the first packet, the eleventh packet, the twenty-first packet, the thirty-first packet,... Of the AV bit stream. In FIG. 5, as in FIG. 2, the packet in which the PCR is recorded is indicated by diagonal lines, and the first packet, the 11th packet, the 21st packet, the 31st packet,. The PCRs recorded in (1), (1), (2) PCR, (3) PCR, (4) PCR,.
[0067]
The division storage unit 23 controls the HDD 24 to store the first half including at least one predetermined packet in which the PCR of the AV bitstream input by the input unit 22 is recorded. It is means for controlling to store in the tape recording device 25 at least the latter half of the recorded AV bit stream after the last packet of the packets in which the PCR stored in the HDD 24 is recorded.
[0068]
The HDD 24 is means for accumulating the first half of the AV bit stream in accordance with the control of the division storing means 23.
[0069]
The tape recording device 25 is means for accumulating the latter half of the AV bit stream in accordance with the control of the division storing means 23.
[0070]
  The connection means 26 uses the packet in which the overlapping PCR of the AV bit stream stored in the HDD 24 and the tape recording device 25 is recorded, and the AV bit stream stored in the HDD 24 and the tape recording device 25. Means for connecting the received AV bitstream. As described above, the connection unit 26 includes the first semiconductor buffer 27, the second semiconductor buffer 28, and the connection control unit 29. The components of the connection unit 26 will be described later.FruitThe operation of the AV bit stream reproduction system according to the second embodiment will be described.
[0071]
  In addition,The first related to the present invention to be described laterInventionAV bitstream recordingIn the system, the HDD 24 and the tape recording device 25 are used as storage means, the input means 22 is used as input means, and the divided storage means 23 is used as control means.
[0072]
  Then like thisFruitThe operations of the AV bit stream recording system and the AV bit stream reproduction system according to the second embodiment will be described.
[0073]
First, the operation of the AV bitstream recording system will be described.
[0074]
First, the input means 22 inputs the AV bit stream shown in FIG.
[0075]
Next, the division storage unit 23 controls the HDD 24 to store the first half including at least one predetermined packet in which the PCR of the AV bitstream input by the input unit 22 is recorded. For convenience of the following description, from the AV bit stream shown in FIG. 5, the fifth bit packet after the packet in which the (n + 2) -th PCR is recorded from the first packet in which the first PCR is recorded is the AV bit stream. In the first half, the split storage unit 23 controls to store the first half in the HDD 24.
[0076]
In addition, the division storage unit 23 stores, in the tape recording device 25, at least the second half of the AV bit stream input by the input unit 22 after the last packet of the packets recorded in the HDD 24. Control to do. For the convenience of the following description, the division storing unit 23 stores the second half of the AV bit stream after the packet in which the n-th PCR is recorded, in the first half of the AV bit stream described above, in the tape recording device 25. Shall be controlled. That is, the portion from the packet in which the n-th PCR is recorded to the packet five times after the packet in which the (n + 2) -th PCR is recorded is accumulated in the HDD 24 and the tape recording device 25. Here, for convenience of the following description, a packet group that is stored in the HDD 24 and the tape recording device 25 is referred to as an overlapping area.
[0077]
Next, the operation of the AV bit stream playback system will be described.
[0078]
First, the connection control means 29 of the connection means 26 inputs the AV bit stream stored in the HDD 24 to the first semiconductor buffer 27 in order from the first packet, temporarily stores it, and outputs it for each packet in the order of storage. . For convenience of the following description, as shown in FIG. 6, the first semiconductor buffer 27 has 10 data storage spaces so that, for example, 10 packets can be temporarily stored for each packet. Suppose you are. Also, first to tenth addresses are assigned to each data storage space. Now, each packet of the AV bit stream from the HDD 24 is temporarily stored for each packet in each data storage space on the first semiconductor buffer 27 under the control of the connection control means 29. For example, each packet is stored in each data storage space so that the first packet is stored in the first data storage space and the second packet is stored in the second data storage space. When, for example, eight packets are temporarily stored in the first semiconductor buffer 27, the connection control means 29 moves the address pointer for outputting the packets to the first data storage space, and the first The first packet temporarily stored in the data storage space is output. Next, the address pointer is moved to the second data storage space, and the second packet is output. Thereafter, in this way, the connection control means 29 moves the address pointer from one data storage space to another data storage space, thereby outputting the packets stored in each data storage space one by one. Further, when the connection control unit 29 outputs the packets one by one, the connection control unit 29 temporarily accumulates the packets from the HDD 24 one by one in each data storage space on the first semiconductor buffer 27. For example, when the first packet is output from the first data storage space, the ninth packet is temporarily accumulated in the ninth data storage space, and when the second packet is output from the second data storage space, The tenth packet is temporarily stored in the data storage space. Further, when the connection control unit 29 outputs the third packet from the third data storage space, the connection control unit 29 inputs the eleventh packet from the HDD 24 to the first data storage space and is stored in the first data storage space until then. The eleventh packet is overwritten on the first packet, and the eleventh packet is accumulated so as to remain in the first data storage space. As described above, the connection control unit 29 inputs the AV bitstream stored in the HDD 24 to the first semiconductor buffer 27 in order from the first packet, temporarily stores it, and outputs it for each packet in the stored order. .
[0079]
Then, the connection control means 29 inputs at least the ((first) overlapping area of the overlapping area near the tail of the AV bit stream stored in the HDD 24 to the first semiconductor buffer 27 and temporarily stores it. n + 2) Any packet in which the nth PCR, the (n + 1) th PCR, or the (n + 2) PCR is temporarily stored in the first semiconductor buffer 27 at that time before the packet in which the PCR is recorded is output. In addition, control is performed so that packets after the packet are input from the tape recording device 25 to the second semiconductor buffer 28 and temporarily stored. The second semiconductor buffer 28 is the same as the first semiconductor buffer 27 as shown in FIG. 6, and 10 packets can be temporarily stored for each packet. Assume that data storage spaces are provided. First to tenth addresses are assigned to the respective data storage spaces. Now, specifically, the connection control means 29 uses, for example, a packet in which the (n + 1) th PCR in the overlapping area is recorded in the first data storage space on the first semiconductor buffer 27 at a predetermined timing. Is temporarily stored, and then the packet in which the (n + 1) th PCR is recorded is output. Before the output, the packet in which the (n + 1) th PCR is recorded is transferred to the tape recording device. 25 and temporarily stored in any data storage space on the second semiconductor buffer 28. Further, the connection control means 29 causes the tape recording device 25 after the packet in which the (n + 1) th PCR is recorded so that the packet from the HDD 24 is temporarily accumulated in each data storage space of the first semiconductor buffer 27. Are temporarily stored in each data storage space of the second semiconductor buffer 28. Here, in FIG. 7, the packet in which the (n + 1) th PCR is recorded and the packet after the packet are temporarily stored in both the first semiconductor buffer 27 and the second semiconductor buffer 28. The block diagram of the 1st semiconductor buffer 27 and the 2nd semiconductor buffer 28 at the time of being carried out is shown. In FIG. 7, the packet in which the (n + 1) th PCR is recorded is indicated by hatching, and the packet in which the (n + 1) PCR is recorded is displayed on the first semiconductor buffer 27. It is assumed that the data is stored in one data storage space and stored in the fifth data storage space on the second semiconductor buffer 28. Further, in FIG. 7, the next packet and the second packet after the packet in which the (n + 1) th PCR is recorded are displayed as packet (1) and packet (2), respectively.
[0080]
Now, as shown in FIG. 7, the packet in which the (n + 1) th PCR is recorded and the packet two packets after the packet are stored in both the first semiconductor buffer 27 and the second semiconductor buffer 28. After being temporarily stored, the connection control means 29 outputs a packet in which the (n + 1) th PCR is recorded from the first data storage space of the first semiconductor buffer 27, and sets the address pointer to the second semiconductor buffer. It moves to 28th 6th data storage space. Then, the connection control unit 29 stores the packet next to the packet in which the (n + 1) th PCR is temporarily stored in the sixth data storage space, that is, the packet (1) is the second semiconductor buffer 28. To be output from Further, the connection control means 29 records all packets after the packet (1) temporarily stored in the sixth data storage space, that is, the (n + 1) th PCR stored in the tape recording device 25. All the packets after the existing packet are sequentially temporarily stored in each data storage space of the second semiconductor buffer 28 and sequentially output. Thus, for example, when a packet in which the (n + 1) th PCR is recorded is accumulated in both the first semiconductor buffer 27 and the second semiconductor buffer 28, the connection control means 29 adds the packet to the packet. Paying attention, the packet stored in the first semiconductor buffer 27 and the packet stored in the second semiconductor buffer 28 are seamlessly connected. In other words, the connections are made accurately so as not to cause duplication or space. At the same time, the connection control means 29 switches between the output of the packet stored in the first semiconductor buffer 27 and the output of the packet stored in the second semiconductor buffer 28. That is, the connection control means 29 connects the AV bit stream stored in the HDD 24 and the AV bit stream stored in the tape recording device 25 using the packet in which the (n + 1) th PCR is recorded, At the same time, the AV bit stream stored in the HDD 24 and the tape recording device 25 is reproduced by switching between the output of the AV bit stream stored in the HDD 24 and the output of the AV bit stream stored in the tape recording device 25.
[0081]
In the second embodiment described above, the overlapping area includes a packet in which the n-th PCR, the (n + 1) -th PCR, and the (n + 2) -th PCR are recorded. As described above, when a plurality of packets in which PCR is recorded are included in the overlapping area, even when the data of the packet to be connected is defective and cannot be reproduced at the time of connection, Connection can be made using the remaining packets in which data is normally recorded. However, if there is a low possibility that any packet data will be defective, the overlapping area only needs to contain one packet in which PCR is recorded.
[0082]
  Further, in the second embodiment described above, as shown in FIG. 4, the division storage means 23 includes the first half including the packet in which the n-th PCR, the (n + 1) th PCR, and the (n + 2) PCR of the AV bitstream are recorded. In this case, control is performed so that all the packets after the packet in which the n-th PCR is recorded are stored in the tape recording device 25. However, as shown in FIG. 8, a copy storage unit 30 is provided as an alternative to the divided storage unit 23 of FIG. The first half of the AV bit stream stored in the tape recording device 25 from the first packet to the packet in which the (n + 2) -th PCR is recorded is copied and stored in the HDD 24. It may be controlled so as to. In this way, connection of packets and switching of output when reproducing the AV bit stream stored in the HDD 24 and the tape recording device 25 are performed as described in the second embodiment. That is, paying attention to a packet in which one of the PCRs is accumulated in the HDD 24 and the tape recording device 25, the packet connection and output switching are performed. In addition,Second invention related to the present invention described laterThe copy storage means 30 was used as the control means of the AV bit stream recording system.
[0083]
In the second embodiment described above, the HDD 24 and the tape recording device 25 use the overlapping area from the packet in which the n-th PCR is recorded to the packet after the packet in which the (n + 2) -th PCR is recorded. Although it is accumulated, the overlapping area accumulated in the HDD 24 and the tape recording device 25 includes a packet in which at least one of the PCRs in the first half of the AV bit stream input by the input unit 22 is recorded. It suffices as long as it is in the area.
[0084]
Further, in the second embodiment described above, paying attention to the packet in which the (n + 1) th PCR is recorded, the packet temporarily accumulated in the first semiconductor buffer 27 and the packet temporarily accumulated in the second semiconductor buffer 28. The packet is connected, but attention is paid to the packet in which the same PCR such as the n-th PCR and the (n + 2) -th PCR stored in both the first semiconductor buffer 27 and the second semiconductor buffer 28 is recorded. The packet temporarily stored in the first semiconductor buffer 27 may be connected to the packet temporarily stored in the second semiconductor buffer 28. In short, paying attention to the packet in which the same PCR stored in both the first semiconductor buffer 27 and the second semiconductor buffer 28 is recorded, the packet temporarily stored in the first semiconductor buffer 27, the first It is only necessary to connect the packet temporarily stored in the second semiconductor buffer 28.
[0085]
In the second embodiment described above, the connection control unit 29 pays attention to the packet in which the (n + 1) th PCR is recorded, and the packet in which the (n + 1) th PCR is recorded from the first semiconductor buffer 27. After the output, the second semiconductor buffer 28 outputs the packet data subsequent to the packet in which the (n + 1) th PCR is recorded. However, the connection control means 29 outputs the packet immediately before the packet in which the (n + 1) th PCR is recorded from the first semiconductor buffer 27, and then the (n + 1) th PCR from the second semiconductor buffer 28. It is also possible to output packets after the packet in which is recorded. In short, the connection control means 29 pays attention to a packet in which one of the PCRs is recorded, which is temporarily accumulated in the first semiconductor buffer 27 and the second semiconductor buffer 28 at a certain timing. Using the packet, it is only necessary to connect the packet temporarily stored in the first semiconductor buffer 27 and the packet temporarily stored in the second semiconductor buffer 28 and switch the output of the packet.
[0086]
In the second embodiment described above, the input unit 22 inputs an AV bit stream including a large number of packets including a plurality of packets in which PCR is recorded. An AV bit stream composed of a large number of packets with time stamps attached to each packet by the time stamp assigning system described in 1 may be input. In this case, since a time stamp is given to each packet, the divided storage unit 23 and the copy storage unit 30 store the first half of the AV bitstream in the HDD 24 and the second half in the tape recording device 25. Can be duplicated and stored in the HDD 24 and the tape recording device 25. Further, when reproducing the AV bit stream stored in the HDD 24 and the tape recording device 25, attention is paid to any packet in the overlapping area, and the packet is used to temporarily store the packet in the first semiconductor buffer 27. And a packet temporarily stored in the second semiconductor buffer 28 from the tape recording device 25 and the output of the packet need only be switched.
[0087]
In the second embodiment described above, as shown in FIGS. 6 and 7, the first semiconductor buffer 27 for temporarily storing packets from the HDD 24 and the packet for temporarily storing packets from the tape recording device 25 are used. The second semiconductor buffer 28 is provided, that is, two buffer spaces are provided. However, a ring buffer having both the function of the first semiconductor buffer 27 and the function of the second semiconductor buffer 28 may be used as an alternative to the first semiconductor buffer 27 and the second semiconductor buffer 28.
[0088]
In the second embodiment described above, the first semiconductor buffer 27 and the second semiconductor buffer 28 have 10 data storage spaces for temporarily storing 10 packets. Is not limited to ten. For example, the first semiconductor buffer 27 and the second semiconductor buffer 28 may have 100 data storage spaces for temporarily storing 100 packets. In addition, since the first semiconductor buffer 27 and the second semiconductor buffer 28 use a considerable amount of capacity for storing packets, it may be considered that the movement of the address pointer or the like is not performed smoothly. In view of this, most of the packets to be accumulated by the first semiconductor buffer 27 and the second semiconductor buffer 28 are further temporarily accumulated before being accumulated in the first semiconductor buffer 27 and the second semiconductor buffer 28. It is possible to provide an HDD capable of reducing the burden on the first semiconductor buffer 27 and the second semiconductor buffer 28.
[0089]
In the second embodiment described above, the division storing unit 23 controls the first half of the AV bit stream input by the input unit 22 to be stored in the HDD 24, and the second half including the overlapping area included in the first half. However, when the second half is stored in the tape recording device 25, the second half is not directly stored in the tape recording device 25, as shown in FIG. It may be accumulated via At that time, a part of the HDD 24 is set in advance so as to have the FIFO function, and the latter part of the AV bit stream is first temporarily stored in the part having the FIFO function, and then all the latter part including the overlapping area is taped. It may be stored in the recording device 25. In this way, even if the tape recording device 25 is not ready for data storage, data can be temporarily stored in the portion of the HDD 24 having the FIFO function. Therefore, after the tape recording device 25 is ready for data storage. There is an effect that the latter half including the overlapping area can be stored in the tape recording device 25.
[0090]
Further, in the second embodiment described above, the first half of the AV bit stream is stored in the HDD 24 and the second half is stored in the tape recording device 25 by devising so as to generate an overlapping area. That is, the example in which the AV bit stream is divided into two and stored in different storage means has been described. However, the AV bit stream may be divided into N or more N (N is a natural number) packet groups, and each may be stored in different storage means. In that case, N storage means are required. Here, it is assumed that each of the N storage units includes storage areas for different storage areas even in the same storage device such as an HDD. Now, when the AV bitstream is divided into three or more N packet groups and each is stored in different storage means, the division storage means 23 and the copy storage means 30 perform the division. Each of the N packet groups includes at least one packet in which a PCR or a time stamp is recorded, and a packet group subsequent to each packet group has a PCR or time stamp included in the immediately preceding packet group. It is necessary to divide the recorded packets so that at least the last packet is duplicated. For example, as shown in FIG. 10, when the AV bit stream is divided into three, PCR or time stamps are recorded in the respective overlapping areas in the same manner as the overlapping areas when divided into two in the second embodiment described above. It must be split so that it contains duplicate packets. Further, when connecting each packet group, a duplicated packet in which a PCR or a time stamp is recorded is used. The connection is performed as described in the second embodiment. Further, N buffers such as the first semiconductor buffer 27 may be prepared corresponding to the N storage means, or two buffers, the first semiconductor buffer 27 and the second semiconductor buffer 28. You may prepare only. In any case, each packet group is connected using two or more buffers. For example, when the copy storage unit 30 divides and stores the AV bit stream into N packet groups, the copy storage unit 30 first stores the entire AV bit stream in one storage unit, and then stores the N packets. All (N-1) packet groups in the group may be copied and stored in different storage means, or some of the (N-1) packet groups may be copied and stored in different storage means. Also good. For example, referring specifically to FIG. 10, the copy storage means 30 first stores all the AV bitstreams in one storage means, and then stores the first overlap area, b, and first of the three packet groups. The two overlapping areas may be stored in another storing means, the second overlapping area and c may be stored in another storing means, or a and the first overlapping area, and c and the second overlapping area may be stored first. Only the first overlap area, b, and the second overlap area may be stored in another storage means while being stored in the storage means stored in the above. That is, it is not necessary to copy and store the second overlapping area and c.
[0091]
  (Embodiment 3)
  Next, the present inventionInventions related toThe configuration of the AV bit stream reproduction system according to the third embodiment will be described.
[0092]
  In FIG.FruitFIG. 9 is a block diagram of an AV bit stream reproduction system according to a third embodiment.
[0093]
  FruitThe AV bit stream reproduction system according to the third embodiment includes an input unit 1, a time stamp generation unit 2, a time stamp addition unit 3, a random access storage device 31, and a time stamp reference reproduction unit 32.
[0094]
The input means 1, time stamp generation means 2 and time stamp assignment means 3 are equivalent to the input means 1, time stamp generation means 2 and time stamp assignment means 3 of the time stamp assignment system of the first embodiment. . Therefore, the time stamp generating means 2 includes a PCR extracting means 4, a counter 5, a difference calculating means 6, a filter means 7, and a VCO 8. The time stamp reference reproduction means 32 is equivalent to the AV bit stream reproduction system of the first embodiment, and includes a FIFO 9, a FIFO management means 10, a time stamp extraction means 11, a second counter 12, The first stamp memory 13, the second stamp memory 14, the stamp value difference calculation means 15, the counter memory 16, the counter value difference calculation means 17, and the difference comparison means 18 are configured.
[0095]
In FIG. 11, the tape recording device 33 is also displayed.
[0096]
Further, as described above, the input unit 1, the time stamp generation unit 2, the time stamp assigning unit 3, and the time stamp reference reproduction unit 32 have already been described in the first embodiment, and thus description thereof is omitted.
[0097]
Now, the random access type storage device 31, for example, in the same manner as the FIFO 9 described in the first embodiment, the AV bit stream packets from the time stamp assigning means 3 are received for each packet in order from the head side of the AV bit stream. It is means for inputting and temporarily storing, and outputting each packet in the order of input and storage in accordance with the instruction of the FIFO management means 10. In short, the random access storage device 31 has a portion having a FIFO function, and is a means capable of temporarily storing packets in the portion having the FIFO function. In the third embodiment, it is assumed that the random access storage device 31 is an HDD.
[0098]
The tape recording device 33 is a unit that stores in advance an AV bit stream similar to the AV bit stream from the broadcasting station that is input by the input unit 1 described in the first embodiment. Therefore, the AV bit stream stored in the tape recording device 33 includes a packet in which PCR is recorded, but no time stamp is given to any packet.
[0099]
  In addition,A third related to the present invention described later.In the AV bit stream reproduction system of the invention, the input means 1 is used as the input means, the random access storage device 31 is used as the storage means, and the FIFO management means 10 of the time stamp reference reproduction means 32 is used as the control means.
[0100]
  Then like thisFruitThe operation of the AV bit stream reproduction system according to the third embodiment will be described.
[0101]
First, the input unit 1 inputs an AV bit stream stored in the tape recording device 33.
[0102]
Then, as described in the first embodiment, the time stamp generating means 2 detects the packet in which the PCR is recorded in the AV bit stream input by the input means 1 and extracts the PCR. The difference from the count value from the counter 5 is calculated by the difference calculation means 6, the voltage of the VCO 8 is controlled so that the difference becomes “zero”, and the time stamp giving means using the count value from the counter 5 as a time stamp 3 is output.
[0103]
When the time stamp giving means 3 inputs the time stamp from the time stamp generating means 2, every time the time stamp is inputted, the time stamp assigning means 3 is added to the header of each packet of the AV bit stream transmitted from the input means 1 at the input timing. Then, a time stamp is given and output to the random access storage device 31.
[0104]
Next, the random access storage device 31 temporarily inputs and stores the packets from the time stamp assigning means 3 in the order of transmission from the time stamp assigning means 3 in the part having the FIFO function. .
[0105]
After that, when a predetermined number of packets such as 10 are accumulated in the random access storage device 31, the FIFO management unit 10 of the time stamp reference reproduction unit 32 controls the random access storage device 31, A predetermined number of packets of the AV bit stream stored in the random access storage device 31 are input to the FIFO 9 for each packet in order from the head of the AV bit stream.
[0106]
The operation of the time stamp reference reproduction means 32 when a predetermined number of packets are input to the FIFO 9 and output from the FIFO 9 for each packet is substantially the same as the operation of the AV bit stream reproduction system of the first embodiment. The description is omitted because it is the same.
[0107]
However, the random access storage device 31 temporarily accumulates the packets to which the time stamps from the time stamp giving means 3 are given in the order of transmission, but the capacity of the part having the FIFO function is limited. Just before reaching or immediately before, the new packet from the time stamp assigning means 3 is overwritten and stored in the area already output to the FIFO 9. By overwriting in this way, the portion having the FIFO function of the random access storage device 31 can be minimized. Then, the random access storage device 31 makes effective use of the portion having the FIFO function, and inputs and temporarily accumulates each packet in the order of transmission from the time stamp assigning means 3, and controls the FIFO management means 10 Accordingly, the packet is output to the FIFO 9 for each packet in order from the head side of the AV bit stream.
[0108]
  In the third embodiment described above, the input unit 1 inputs the AV bit stream from the tape recording device 33, but the input unit 1 receives the AV bit stream from the tape recording device 33 as shown in FIG. Instead of the stream, an AV bit stream stored in the tape recording device 34 may be input. The AV bit stream stored in the tape recording device 34 is an AV bit stream according to the DV format, unlike the AV bit stream according to the MPEG2 standard stored in the tape recording device 33. As shown in FIG. 13, one frame of the DV format AV bit stream is composed of a header part, a DC component part, and an AC component part, and each part is packetized. Therefore, the DV format AV bit stream, that is, the AV bit stream stored in the tape recording device 34 is composed of a large number of frames as shown in FIG. In addition, video and / or sound data is recorded in the AC component portion of the three portions of one frame, and a time stamp is assigned in advance to all packet data constituting the DV format AV bit stream. ing. As described above, when the input unit 1 inputs the AV bit stream from the tape recording device 34, since all the packets of the AV bit stream are time stamped, the time stamp generating unit 2 shown in FIG. And the time stamp assigning means 3 is not necessary. Instead, as shown in FIG. 12, packet data extraction means 35 is provided, and in this packet data extraction means 35, an AC component part in which AV data is recorded from an AV bit stream in DV format input by the input means 1 Must be extracted one by one and output to the random access storage device 31 in order from the beginning of the AV bitstream and for each packet. 12 is not provided with the time stamp generating means 2 shown in FIG. 11, or more specifically, the VCO 8, so in FIG. 12, as a substitute for the second counter 12 in FIG. It is necessary to provide a fourth counter 37 that has a unique vibrator that vibrates at a frequency that allows an allowable range, and that counts according to the vibration of the vibrator. Then, the packet temporarily stored in the random access storage device 31 with the count value of the fourth counter 37 as a reference is output via the FIFO 9.
  (Embodiment 4)
  Next, the present inventionInventions related toThe configuration of the AV bit stream recording system according to the fourth embodiment will be described.
[0109]
  In FIG.FruitFIG. 10 is a block diagram of an AV bit stream recording system according to a fourth embodiment.
[0110]
  FruitThe AV bit stream recording system according to the fourth embodiment includes an input unit 1, a time stamp generation unit 2, a time stamp addition unit 3, a random access storage device 31, and a time stamp reference reproduction unit 32.
[0111]
The input means 1, time stamp generation means 2, time stamp assignment means 3, random access storage device 31, and time stamp reference reproduction means 32 are the same as those described in the third embodiment.
[0112]
In FIG. 14, the tape recording device 38 is also displayed.
[0113]
  Also,A fourth related to the present invention described later.In the AV bit stream recording system of the invention, the input means 1 is used as input means, the random access storage device 31 is used as storage means, and the FIFO management means 10 of the time stamp reference reproduction means 32 is used as control means.
[0114]
  Then like thisFruitThe operation of the AV bit stream recording system of the fourth embodiment will be described.
[0115]
First, the input unit 1 inputs an AV bit stream from a broadcasting station, similarly to the input unit 1 described in the first embodiment.
[0116]
Then, the time stamp generating means 2 generates a time stamp to be given to each packet of the AV bit stream and outputs it to the time stamp giving means 3.
[0117]
When the time stamp giving means 3 inputs the time stamp from the time stamp generating means 2, every time the time stamp is inputted, the time stamp assigning means 3 is added to the header of each packet of the AV bit stream transmitted from the input means 1 at the input timing. Then, a time stamp is given and output to the random access storage device 31.
[0118]
Next, the random access storage device 31 temporarily inputs and stores the packets from the time stamp assigning means 3 in the order of transmission from the time stamp assigning means 3 in the part having the FIFO function. .
[0119]
After that, when a predetermined number of packets such as 10 are accumulated in the random access storage device 31, the FIFO management unit 10 of the time stamp reference reproduction unit 32 controls the random access storage device 31, A predetermined number of packets of the AV bit stream stored in the random access storage device 31 are input to the FIFO 9 for each packet in order from the head of the AV bit stream.
[0120]
When a predetermined number of packets are input and temporarily stored in the FIFO 9, the FIFO 9 outputs the packets in the order of storage in accordance with the control of the difference comparison means 18. Note that the detailed operation of the time stamp reference reproduction means 32 when a packet is output from the FIFO 9 is the operation of the time stamp reference reproduction means 32 of the AV bit stream reproduction system of the third embodiment. Since the operation is substantially the same as that of the 1 AV bitstream playback system, detailed description thereof is omitted.
[0121]
The packet output from the FIFO 9, that is, the AV bit stream is recorded in the tape recording device 38.
[0122]
Here, as in the above-described third embodiment, the random access storage device 31 uses the portion having the FIFO function effectively, and the packet to which the time stamp is given from the time stamp assigning means 3 is transmitted. The packets are temporarily stored for each packet in order, and output to the FIFO 9 for each packet in order from the beginning of the AV bitstream according to the control of the FIFO management means 10.
[0123]
In the fourth embodiment described above, the packet from the random access storage device 31 is recorded on the tape recording device 38 via the time stamp reference reproduction means 32. However, as shown in FIG. The DV format conversion means 39 is used instead of the reference reproduction means 32, and the DV format conversion means 39 converts the packet from the random access type storage device 31 into a DV format AV bit stream and records it on the tape recording device 38. You may let them. That is, as shown in FIG. 13, the DV format conversion means 39 writes the packet data from the random access storage device 31 to the AC component part, and adds the header part and the DC component part to the tape recording device 38 for recording. You may let them.
[0124]
In the third and fourth embodiments described above, as described with reference to FIGS. 11 and 14, the second counter 12 of the time stamp reference reproduction unit 32 uses the timing control signal from the VCO 8 of the time stamp generation unit 2 as the timing control signal. Work on the basis. As described above, since each constituent unit of the time stamp reference reproduction unit 32 operates based on the timing control signal from the VCO 8, the random access storage device 31 outputs one packet at substantially the same cycle. A new packet can be input. That is, the overflow and underflow of the FIFO function packet of the random access storage device 31 can be avoided. However, if the length of the AV bit stream input by the input means 1 is short enough not to cause overflow or underflow of the FIFO function packet of the random access storage device 31, the second counter 12 receives the signal from the VCO 8. The operation may not be performed based on the timing control signal. That is, the operation may be performed based on a unique reference clock. Further, when the AV bit stream input by the input means 1 is an AV bit stream using a reference clock having a period exceeding an allowable range such as 27 MHz ± 30 ppm, the second counter 12 receives the timing from the VCO 8. Disable operation based on the control signal. That is, the operation is performed based on a specific reference clock.
[0125]
  (Embodiment 5)
  Next, the present inventionInventions related toThe configuration of the AV bit stream reproduction system according to the fifth embodiment will be described.
[0126]
  In FIG.FruitFIG. 10 shows a block diagram of an AV bit stream reproduction system according to a fifth embodiment.
[0127]
  FruitThe AV bit stream reproduction system according to the fifth embodiment includes an input unit 40, a time stamp generation unit 2, a time stamp assigning unit 3, a gate unit 41, a random access storage device 42, and a time stamp reference reproduction unit 32. Consists of The random access storage device 42 includes an index area 43, a FIFO area 44, a first semiconductor buffer RAM space 45, a second semiconductor buffer RAM space 46, and a third semiconductor buffer RAM space 47. It is what you have.
[0128]
  In addition, FIG.6The tape recording device 48 is also displayed.
[0129]
Further, since the time stamp generating means 2, the time stamp giving means 3 and the time stamp reference reproducing means 32 have already been described in the third embodiment, the description thereof will be omitted.
[0130]
The input means 40 is a means for inputting the AV bit stream stored in the tape recording device 48.
[0131]
The gate means 41 is means for temporarily recording each packet of the AV bit stream input by the input means 40 in an appropriate location in the third semiconductor buffer RAM space 47 of the random access storage device 42.
[0132]
As described above, the random access storage device 42 includes the index area 43, the FIFO area 44, the first semiconductor buffer RAM space 45, the second semiconductor buffer RAM space 46, and the third semiconductor buffer RAM space. 47. The index area 43 and the FIFO area 44 are areas each composed of a ring buffer, and the index area 43 is an area in which several packets at the beginning of a predetermined AV bit stream can be stored. 44 is an area having a FIFO function, in which each packet of the AV bit stream input by the input means 40 is input and temporarily stored for each packet in order from the head side of the AV bit stream. This is an area where packets are output in order. The first semiconductor buffer RAM space 45, the second semiconductor buffer RAM space 46, and the third semiconductor buffer RAM space 47 are spaces formed using semiconductors, and are the first described in the second embodiment. The semiconductor buffer 27 or the second semiconductor buffer 28 is the same. That is, the first semiconductor buffer RAM space 45, the second semiconductor buffer RAM space 46, and the third semiconductor buffer RAM space 47 are spaces each having a FIFO function. However, the first semiconductor buffer RAM space 45 is a space for temporarily storing packets from the index area 43, and the second semiconductor buffer RAM space 46 is a space for temporarily storing packets from the FIFO area 44. The third semiconductor buffer RAM space 46 is a space for temporarily storing each packet of the AV bit stream input by the input means 40.
[0133]
The tape recording device 48 is a recording device that records in advance an AV bit stream composed of a large number of packets including a packet in which a PCR is recorded, as described in the first embodiment.
[0134]
  Then like thisFruitThe operation of the AV bit stream reproduction system according to the fifth embodiment will be described.
[0135]
First, it is assumed that the index (starting portion) of the AV bit stream recorded in the tape recording device 48 is stored in the index area 43 of the random access storage device 42 in advance. It is assumed that the index includes at least one packet recorded in the tape recording device 48 and recorded with PCR. Here, for convenience of the following description, it is assumed that there are three packet data in which PCR is recorded, and each PCR is first PCR, second PCR, and third PCR in order from the beginning of the AV bitstream. Therefore, in the fifth embodiment, as described in the second embodiment, the index (first part) stored in advance in the index area 43 and the AV bit stream recorded in the tape recording device 48 are connected. The operation of the AV bit stream reproduction system when the output is switched to reproduce the AV bit stream will be described. Here, for convenience of explanation, a scene in which an AV bit stream is connected will be described by focusing on the second PCR described above.
[0136]
Now, when reproducing the AV bit stream recorded in the index area 43 and the tape recording device 48, first, the packets in the index area 43 are accumulated in the first semiconductor buffer RAM space 45 in order from the beginning, and the order in which they are accumulated. To output. Then, the second PCR recorded in the index area 43 and the tape recording device 48 is recorded in the first semiconductor buffer RAM space 45 until the second PCR is recorded and output. The gate means 41 is input by the input means 40 so that the recorded packets are accumulated in the second semiconductor buffer RAM space 46 from the tape recording device 48, and the time stamp is given by the time stamp giving means 3. The packet is accumulated in the third semiconductor buffer RAM space 47. Further, the third semiconductor buffer RAM space 47 is so stored that a packet in which the second PCR is recorded at a certain timing is temporarily stored in both the first semiconductor buffer RAM space 45 and the second semiconductor buffer RAM space 46. Are temporarily stored in the second semiconductor buffer RAM space 46 sequentially through the FIFO area 44 of the random access storage device 42.
[0137]
When a packet in which the second PCR is recorded at a certain timing is temporarily accumulated in both the first semiconductor buffer RAM space 45 and the second semiconductor buffer RAM space 46, the second PCR is recorded in duplicate. Using the packet in which 2PCR is recorded, the address pointer is moved as described in the second embodiment, the packet stored in the first semiconductor buffer RAM space 45, and the second semiconductor buffer RAM space The packet stored in 46 is connected, and the output after the connection is switched to the packet stored in the second semiconductor buffer RAM space 46. In this way, the AV bit stream recorded in the index area 43 and the tape recording device 48 is connected and reproduced. In FIG. 16, a packet in which the second PCR is recorded, which is recorded in duplicate, is indicated by hatching.
[0138]
Then, the time stamp reference reproduction means 32 reproduces and outputs the packet from the first semiconductor buffer RAM space 45 or the second semiconductor buffer RAM space 46 as described in the first embodiment.
[0139]
In the above-described fifth embodiment, when the packet stored in the first semiconductor buffer RAM space 45 and the packet stored in the second semiconductor buffer RAM space 46 are connected, the second PCR records. Suppose that you use the packet that is. However, in the first semiconductor buffer RAM space 45 and the second semiconductor buffer RAM space 46, when a packet in which the same PCR other than the second PCR is recorded is accumulated redundantly, the redundant accumulation is performed. It is also possible to use a long packet. Alternatively, when packets having the same time stamp are simultaneously accumulated in the first semiconductor buffer RAM space 45 and the second semiconductor buffer RAM space 46, the same time is accumulated. A packet to which a stamp is attached may be used.
[0140]
In the first to fifth embodiments described above, the MPEG2 AV bit stream has been described. However, as with the MPEG2 AV bit stream, a plurality of packet data in which time information such as PCR is recorded in advance is included. In the case of an AV bit stream composed of a large number of packet data, the AV bit stream may be used as an alternative to the MPEG 2 AV bit stream of the first to fifth embodiments described above.
[0141]
In the first to fifth embodiments described above, the PCR is time information indicating the reproduction timing of a specific packet. However, when further explanation is added here, the PCR is generally in the digital broadcast receiver. This is used as information constituting the reference clock.
[0142]
In the first to fifth embodiments described above, each component of the time stamp assigning system and the AV bitstream playback system AV bitstream recording system in each embodiment has been described as hardware. It is also possible to replace all or part of the constituent elements with software having the same function as the corresponding function of the hardware described above.
[0143]
  Furthermore, the present invention also relates to a program recording medium that stores a program for causing a computer to execute all or some of the functions of each component of the time stamp assigning system described in the first embodiment.Inventions related toIt is. Similarly, a program for causing a computer to execute all or a part of each function of each component of the AV bitstream reproduction system described in the first, second, third, and fifth embodiments is stored. The program recording medium is also the present invention.Inventions related toIt is. In addition, a program recording medium characterized by storing a program for causing a computer to execute all or a part of each function of each component of the AV bitstream recording system described in the second and fourth embodiments. The present inventionInventions related toIt is.
A first invention related to the present invention includes N (N is a natural number) accumulation means capable of accumulating a predetermined AV bitstream;
A stream of packets in which video and / or audio data is packetized, and reproduction timing information indicating reproduction timings of the predetermined plurality of packets is recorded in the predetermined plurality of packets. Input means for inputting an AV bitstream;
Control means for controlling the AV bit stream input by the input means to be divided into N packet groups and separately stored in the N storage means,
Each of the N packet groups has at least one packet in which the reproduction timing information is recorded,
When the control means performs the division, a packet group subsequent to each packet group of the N packet groups is at least the last of the packets in which the reproduction timing information included in the immediately preceding packet group is recorded. Split so that it has duplicates after packet
This is an AV bit stream recording system.
According to a second aspect of the present invention, N (N is a natural number) accumulating means capable of accumulating a predetermined AV bitstream;
A stream of packets in which video and / or audio data is packetized, and reproduction timing information indicating reproduction timings of the predetermined plurality of packets is recorded in the predetermined plurality of packets. Input means for inputting an AV bitstream;
The AV bit stream input by the input means is controlled to be stored in a predetermined one of the N storage means, and then the AV bit stream stored in the predetermined storage means is The packet is divided into N packet groups, and all or a part of the (N-1) packet groups of the N packet groups are stored in (N-1) storage units other than the predetermined storage unit. And a control means for controlling the copy so as to be separately accumulated in whole or in part,
Each of the N packet groups has at least one packet in which the reproduction timing information is recorded,
When the control means performs the division, a packet group subsequent to each packet group of the N packet groups is at least the last of the packets in which the reproduction timing information included in the immediately preceding packet group is recorded. Split so that it has duplicates after packet
This is an AV bit stream recording system.
A third invention related to the present invention is a packet stream in which video and / or audio data is packetized, and the predetermined plurality of packets are reproduced into the predetermined plurality of packets. Input means for inputting an AV bit stream from a magnetic tape on which AV bit stream is recorded, in which reproduction timing information indicating timing is recorded;
Storage means capable of temporarily storing a predetermined AV bitstream;
Each packet of the AV bit stream input by the input means is temporarily stored in the storage means in the input order, and each packet is stored in the order in the storage means Control means to output from
An AV bit stream reproduction system characterized by comprising the above.
A fourth invention related to the present invention is a packet stream in which video and / or audio data is packetized, and the predetermined plurality of packets are reproduced into the predetermined plurality of packets. Input means for inputting an AV bit stream in which reproduction timing information indicating timing is recorded;
Storage means capable of temporarily storing a predetermined AV bitstream;
Each packet of the AV bit stream input by the input unit is temporarily stored in the storage unit in the input order, and each packet is output from the storage unit in the order and recorded on a predetermined magnetic tape. Control means
An AV bit stream recording system comprising the above.
The invention related to the present invention can provide an AV bitstream recording system for recording an AV bitstream so that the AV bitstream can be accurately connected even when the AV bitstream has no scene specified. . Further, the invention related to the present invention can provide an AV bit stream reproduction system for accurately connecting and reproducing AV bit streams.
Furthermore, the invention related to the present invention provides an AV bit stream reproduction system and an AV bit stream recording system capable of temporarily accumulating a large amount of data and quickly reproducing and outputting the accumulated data in the order of accumulation. Can do.
[0144]
【The invention's effect】
As is apparent from the above description, the present invention generates a substantially fixed reference clock based on time information recorded in advance in the AV bitstream, and sets a time stamp according to the substantially fixed reference clock. A time stamp assigning system that generates and assigns each packet can be provided. In addition, the present invention can provide an AV bit stream reproduction system that reproduces each packet to which a time stamp is attached in accordance with the substantially fixed reference clock described above.
[Brief description of the drawings]
FIG. 1 is a block diagram of a time stamp assigning system and an AV bit stream reproduction system according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of an AV bit stream used for explaining the first embodiment of the present invention.
FIG. 3 is a block diagram of a time stamp assigning system and an AV bit stream reproducing system according to Embodiment 1 of the present invention different from FIG.
FIG. 4 The present inventionInventions related toBlock diagram of AV bit stream recording system and AV bit stream playback system of Embodiment 2
FIG. 5 shows the present invention.Inventions related toOf AV bit stream used for explanation of the second embodiment of the present invention
FIG. 6Inventions related toHDD 24, tape recording device 25, first semiconductor buffer 27, and second semiconductor buffer 28 used in the description of the second embodiment.
7 is a view different from FIG.Inventions related toHDD 24, tape recording device 25, first semiconductor buffer 27, and second semiconductor buffer 28 used in the description of the second embodiment.
FIG. 8 is another embodiment of the present invention different from FIG.Inventions related toBlock diagram of AV bit stream recording system and AV bit stream playback system of Embodiment 2
FIG. 9 is another embodiment of the present invention different from FIGS.Inventions related toBlock diagram of AV bit stream recording system and AV bit stream playback system of Embodiment 2
FIG. 10 shows the present invention.Inventions related toThe figure for demonstrating the case where an AV bit stream is divided into 3 used for description of Embodiment 2 of FIG.
FIG. 11 shows the present invention.Inventions related toBlock diagram of an AV bitstream reproduction system according to Embodiment 3 of the present invention
12 is a view different from FIG.Inventions related toBlock diagram of an AV bitstream reproduction system according to Embodiment 3 of the present invention
FIG. 13 shows the present invention.Inventions related toConfiguration diagram of one frame of DV format AV bit stream used in the third embodiment
FIG. 14 shows the present invention.Inventions related toBlock diagram of the AV bit stream recording system of Embodiment 4
15 is a view of the present invention different from FIG.Inventions related toBlock diagram of the AV bit stream recording system of Embodiment 4
FIG. 16 shows the present invention.Inventions related toBlock diagram of an AV bitstream playback system according to the fifth embodiment

Claims (4)

A stream of packetized packet includes data of the video and / or sound, Oite their predetermined plurality of packets, an input means for time information indicating a playback timing to input the AV bitstream stored When,
Oscillating means for oscillating a timing control signal whose oscillation cycle is controlled based on a plurality of the time information of a packet in which the time information is stored in the AV bit stream input by the input means;
A time for generating a reference clock using the timing control signal of the oscillating means and generating a time stamp indicating the reproduction timing of each packet of all the packets or at least all the packets in which the time information is not stored A stamp generating means;
A time stamp giving means for giving the time stamp generated by the time stamp generating means to each packet corresponding to the time stamp ;
Includes a time stamping system having a further,
Temporary storage means for inputting, temporarily storing and outputting the AV bit stream output from the time stamp assigning system in units of packets in order from the top of the AV bit stream;
The output timing of the packet output from the temporary storage means is determined based on the time stamp given to all or part of the packets of the AV bitstream, and the timing control signal oscillated by the oscillation means is used. Control means for controlling to output from the temporary storage means in synchronization with the generated reference clock;
An AV bitstream recording / reproducing system comprising: The said control means switches the said reference clock produced | generated using the said timing control signal based on the said time information oscillated by the said oscillation means, and a specific reference clock, The said reference clock is characterized by the above-mentioned. AV bitstream recording / playback system. 3. The AV bit according to claim 2, wherein the control means switches to the specific reference clock when a period of the reference clock generated using the timing control signal exceeds a predetermined allowable range. Stream recording / playback system. An input means for inputting an AV bit stream that is a packetized packet stream including video and / or audio data and in which time information indicating reproduction timing is stored in the predetermined plurality of packets;
Oscillating means for oscillating a timing control signal whose oscillation cycle is controlled based on a plurality of the time information of a packet in which the time information is stored in the AV bit stream input by the input means;
A time for generating a reference clock using the timing control signal of the oscillating means and generating a time stamp indicating the reproduction timing of each packet of all the packets or at least all the packets in which the time information is not stored A stamp generating means;
Time stamp giving means for giving the time stamp generated by the time stamp generating means to each packet corresponding to the time stamp;
A time stamping system having
Temporary storage means for inputting, temporarily storing and outputting the AV bit stream output from the time stamp assigning system in units of packets in order from the top of the AV bit stream;
Wherein the AV bit stream, all or based on the time stamp added to a portion of the packet to determine the output timing of the packet to be output from the temporary storage means, the reference clock that uses the vibration of unique vibrators Control means for controlling to output from the temporary storage means synchronously;
An AV bitstream recording / reproducing system comprising:

Images