KR100217742B1 - Method and circuit of data recording for television signal recording - Google Patents

Abstract

The present invention relates to an information recording circuit having a structure of five sync blocks of a television receiver, in which screen sequence information for recording a program clock reference value (PCR) of the five sync blocks and informing the order of the screen is provided. Record the presentation time stamp (PTS) value when the normal playback data is recorded, and perform the extra PCR for trick playback on the presentation time stamp (PTS) including the screen. Recorded in the area, it is characterized in that the playback from the desired portion during normal playback.

Description

Data recording circuit for TV signal recording

1 is a trick structure diagram of a standard density (SD) tape.

2 is a diagram of sync block and transport packet mapping.

3 is a circuit diagram according to an embodiment of the present invention.

4 is a circuit diagram according to another embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ATV (Advanced TV) / DVB (Digital Video Board casting) recording circuit, and in particular, to ATV / DVB data enabling efficient switching from trick play to normal play. A data recording circuit for recording a television signal for recording.

The trick play relates to a special function used for high-speed search and the like in a VCR, and means an example of playing at a speed higher than normal play. The conventional ATV / DVB broadcasting method uses an MPEG-2 bit stream. However, to record this, the tape used in the standard definition (SD) is used as it is. To this end, in the related art, data must be newly configured in a structure suitable for a format of a standard density tape, and thus, there is a problem in that the existing format cannot efficiently provide a trick play function at a desired portion.

Accordingly, an object of the present invention is to provide a circuit capable of recording normal ATV / DVB broadcast signals on a recording medium such as a tape, and efficiently performing normal reproduction in trick reproduction.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a trick structure diagram of a standard definition (SD) tape,

(a) is an example of the position of a sync block (SB) on a track;

(b) shows the structure of a sync block SB.

2 shows an example of mapping of a sync block SB to a transport.

3 is a circuit diagram according to an embodiment of the present invention.

A demultiplexer 301 which demultiplexes the data input from the transport stream data stage TS and separates and outputs the audio and video data;

A pure video data extraction unit 303 for extracting only pure video data from the transport packet format video of the demultiplexer 301,

A program clock reference and presentation time for extracting a program clock reference value (PCR) and a presentation time stamp value (PTS) from the pure video data extracted by the pure video data extractor 303. A stamp value extractor 302, a trick data extractor 305 for extracting trick data from the output of the pure video data extractor 303,

A counter value extractor 304 for extracting a counting value corresponding to a Group of Picture (GOP) from the output of the pure video data value of the trick data extractor 305;

A transport packet constructing unit 306 constituting a transport packet (TP) from the trick data extracted by the trick data extracting unit 305;

The transport clock configuration unit 306 receives the output value of the program clock reference and presentation time stamp value extraction unit 302 from the counter value extraction unit 304 as shown in FIG. A first synchronous block unit configuring unit 308 composed of five sync blocks (5 SB),

The video clock data in the form of a transport packet is received from the output value of the program clock reference and presentation time stamp value extractor 302 and the extract value of the counter value extractor 304. As shown in FIG. And a second synchronous block unit constitution unit 309 constituting 5 SB).

4 is another embodiment according to an embodiment of the present invention,

A demultiplexer 301 for demultiplexing data input from the transport stream data stage TS and separating the data into audio and video data and outputting the demultiplexer 301;

A program clock reference and presentation time stamp value extraction unit 302 for extracting a program clock reference value (PCR) and a presentation time stamp value (PTS) from the output of the demultiplexer 301,

A trick data extractor 305 for extracting trick data from the output video data separated by the demultiplexer 301;

A counter value extractor 304 for extracting a counting value corresponding to a group of pictures (GOP) from the output of the trick data extractor 305, and

A transport packet constructing unit 306 constituting a transport packet (TP) from the trick data extracted by the trick data extracting unit 305;

According to the program clock reference value and the presentation time stamp value extracted by the program clock reference and presentation time stamp value extracting unit 302, the transport packet TP configuration unit ( The output of 306 and the output of the demultiplexer 301 are composed of first and second sync block unit components 308 and 309 constituting five sync blocks.

Therefore, a specific embodiment of the present invention will be described in detail with reference to FIGS. 1 to 4.

In general, the ATV / DVB broadcasting method uses an MPEG-2 bitstream. However, the tape for recording the same is used as the tape used in the standard definition (SD). As a result, data must be newly configured in a structure that conforms to the format of a standard density (SD) tape. Therefore, the data used in the transport layer of the MPEG-2 is configured in units of 188 bytes. The data format of the tape is different. The mapping between the format of the standard density (SD) and the transport packet is shown in FIGS. 1 and 2. As shown in Fig. 1 (b), one sync block SB is composed of 90 bytes, but the area for data recording is allocated 77 bytes. The relationship between the sync block and the transport packet is as shown in FIG. One of the 77 bytes is reserved for other information, and 76 × 5 (= 380) bytes are used to hold two transport packets (188 × 2). As shown in FIG. 2, an extra three bytes are placed in each middle portion of the first sync block SB0 and the third sync block SB2, and the additional information indicating the order of the screen is stored here. Calculating the number of bytes, (76 × 5-6) / 2 = 187. This means that only 187 bytes are recorded except for the first byte of the transport packet, the sync byte (having a fixed value of 0x47). Here, in order to make five sync blocks SB as one unit, and to make five sync blocks as one unit, the first and second sync block unit components 308 and 309 shown in FIGS. Is made. This is called 5 sync block units. Here, how to configure the information to be recorded in the extra three bytes, the data input from the transport data stage (TS) in the demultiplexer 301 to the audio and video data in the demultiplexer (301) Separate. Only the pure video data is extracted from the pure video data extracting unit 303, and the presentation time stamp is a time value for displaying when the program clock reference value (PCR) and the screen should appear for synchronization of the system. When the value PTS is extracted by the program clock reference and presentation time stamp value extracting unit 302 and inputted to the first and second sync block unit configuring units 308 and 309, the value PTS is recorded in an extra 3 bytes of the sync block unit. In the case of the normal reproduction data, the PCR records the PCR value at the point of time when the data is processed, and in the case of the screen constituting the trick reproduction screen, the PCR value is stored and then the sync block SB of the trick reproduction data is stored. Write in 3 extra bytes.

The PCR consists of 42 bits, and since only 21 bits are used, only the upper 21 bits of the PCR are recorded. Meanwhile, in the case of the PTS, it means a time when a screen should be provided, that is, a value indicating when the screen should be displayed. When recording the normal playback data, the PST value of the data is recorded in the extra 3 bytes, and the screen for trick play is extracted. The PTS value of the data including the screen used is used as the sync block (SB) for the trick play data. Write in 3 extra bytes. At this time, as in the case of PCR, only the upper 21 bits of the PTS are recorded (the PTS consists of 33 bits). In the case of the trick data, the trick data extracting unit 305 extracts the pure video data, and transports the packet to the transport packet in the transport packet construction unit 306, and outputs and programs the demultiplexer 301. The extracted reference values of the clock reference and presentation timestamp value extracting unit 302 are input to the first and second synchronous block unit forming units 308 and 309 and mapped as shown in the first and second degrees. As shown in FIG. 2, an extra 3 bytes is stored in the middle of the first sync block SB0 and the fourth sync block SB3, and additional information indicating the order of the screen is stored therein. The byte is composed of 24 bits. The upper 3 bits are not used, and only the lower 21 bits are used to store information. First, the first method is to record the counter value of the counter value extractor 304 simply. . In other words, in the process of decoding the video stream, a counter that counts the number of group of pictures (GOP) is provided, and the counter value at that time is recorded in the extra 3 bytes of the SB unit containing the normal playback data. In the extra 3 bytes of the SB unit containing the trick playback data, the counter value of the original screen that constitutes the trick playback screen is recorded. If you stop using this trick, you can find the position of the original screen so that you can see it from the place you want during normal playback.

Alternatively, a Program Clock Reference (PCR) value may be recorded.

In MPEG-2 systems, the clock is used as a reference for system synchronization, and that is PCR. In the case of the normal reproduction data, the PCR value at the point of time when the data is processed is recorded. In the case of the screen constituting the trick reproduction screen, the PCR value is stored and recorded in the extra 3 bytes of the trick reproduction data SB. Note that PCR consists of 42 bits. Since only 21 bits are used here, only the top 21 bits of the PCR are recorded. The last value to suggest is the PTS (Presentation Time Stamp). The MPEG-2 transport stream has a value of PTS, which means the time when a picture should be provided. That is, a value indicating when the screen should be displayed. When the normal reproduction data is recorded, the PTS value of the data is recorded in an extra 3 bytes, and the trick reproduction screen is extracted. The PTS value of the data including the screen used here is added to the SB unit for the trick reproduction data. Write to 3 bytes of. At this time, as in the case of PCR, only the upper 21 bits of the PTS are recorded (the PTS consists of 33 bits). In other words, the output from the device that separates components such as video and audio from the transport stream of the demultiplexer 301 of FIG. 3 has a form of a transport packet. In this case, it is necessary to select only pure video data in the path for trick reproduction once again, and FIG. 4 shows a case where the output of the demultiplexer 301 is pure video data. In FIG. 4, the program clock reference and presentation time stamp value extractor 302 extracts PCR and PTS and the counter extractor 304 extracts all the counter values. It is decided accordingly. In other words, when the PTS is recorded in the extra 3 bytes, the PTS is extracted. At this time, no other part, that is, a part for extracting the counter value of the counter extractor 304 or a part for extracting PCR from the program clock reference and presentation time stamp value extractor 302, is present in the system.

If the data is arranged as above and stopped at the desired part during the trick play, the VCR reads the value of the 3-byte free area in the trick play part at the time and reads the value of the area having the same value in the normal play data. By positioning the head, it is possible to play from the desired portion during normal playback, and there is an advantage that the trick playback can be efficiently performed as a data format for recording ATV / DVB broadcast on a medium such as tape.

Claims (2)

A data recording circuit for recording a signal of a television receiver, comprising: a demultiplexer for demultiplexing data input from the transport stream data stage 75 of the television receiver to separate audio and video data and output the demultiplexer 301, a pure video data extractor 303 for extracting only pure video data from the transport packet format video of the demultiplexer 301, and a program from pure video data of the pure video data extractor 303. A program clock reference and presentation time stamp value extractor 302 for extracting a clock reference value PCR and a presentation time stamp value PTS and trick data from the output of the pure video data extractor 303 are extracted. The trick data extractor 305 and the pure video data value of the trick data extractor 305 A counter value extractor 304 for extracting a counting value corresponding to a GOP from an output, and a transport packet constructer 306 for constructing a transport packet TP from the trick data extracted by the trick data extractor 305. And the output values of the program packet reference and presentation time stamp value extractor 302 from the output value of the counter value extractor 304 and the output of the transport packet constructor 306. A first synchronous block unit configuring unit 308 configured to (5 SB), an output value of the program clock reference and presentation time stamp value extracting unit 302, and a truncated value of the counter value extracting unit 304; 2. A data recording circuit for recording a television signal, characterized in that it comprises a second synchronous block unit construction unit (309) for receiving video data in a port packet format and forming it into five blocks (5 SBs). A data recording circuit for recording a signal of a television receiver, comprising: a demultiplexer for demultiplexing data input from the transport stream data stage 75 of the television receiver to separate audio and video data and output the demultiplexer 301, a program clock reference and presentation time stamp value extractor 302 for extracting a program clock reference value PCR and a presentation time stamp value PTS from an output of the demultiplexer 301, and the demultiplexer 302. A trick data extractor 305 for extracting trick data from the output video data separated at 301, and a counter value extractor 304 for extracting a counting value corresponding to a GOP from the output of the trick data extractor 305. And a transformer constituting a transport packet TP from the trick data extracted by the trick data extractor 305. From the output of the counter value extraction section 304 by the program packet reference section 306 and the program clock reference and presentation time stamp value extraction section 302 extracted from the program clock reference and presentation time stamp value extraction section 302. And a first and second sync block unit configuring units 308 and 309 constituting five sync blocks by the output of the transport packet (TP) configuration unit 306 and the output of the demultiplexer 301. Data recording circuit for TV signal recording.