JP3589587B2 - Recording / playback device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a digital signal device for recording / reproducing a video digital signal, and relates to a device for performing mode control by detecting a mode change of a reproduced signal when reproducing a digital signal.
[0002]
[Prior art]
In recent years, with the development of digital signal processing technology, devices for recording and reproducing digital data obtained by encoding video signals and the like with high efficiency have become widespread.
In this recording / reproducing apparatus, in order to improve the usability of digital data, video AUX data (hereinafter, referred to as "VAUX data") such as a broadcast system, a recording mode, a recording date, a recording time, minute, second and the like are added at the time of recording. ing.
Japanese Patent Application Laid-Open No. Hei 9-186968 proposes a method of adding the VAUX data to video digital data at the time of recording and detecting the VAUX data from the reproduced data at the time of reproduction to control the reproduction mode.
[0003]
FIG. 5 is a block diagram showing the configuration of the recording / reproducing apparatus described in the above publication. In the figure, 1 is a data compression encoding circuit, 2 is a shuffling memory, 3 is a framing circuit, 4 is a multiplexer (MUX), 5 is an error correction code adding circuit, 6 is a channel encoder, 7 is a mode processing microcomputer, 8 Is a signal processing microcomputer, 9 is a reproduction circuit, 10 is a channel decoder, 11 is an error correction circuit, 12 is a demultiplexer (DMUX), 13 is a deframing circuit, and 14 is a data compression / decoding circuit.
[0004]
Hereinafter, the operation of the conventional recording / reproducing apparatus will be described.
First, at the time of recording, an input digital video signal is shuffled by a data compression encoding circuit 1 using a shuffling memory 2 to obtain a data compression code such as DCT (discrete cosine transform), quantization, and variable length encoding. The framing circuit 3 performs frame processing. The mode processing microcomputer 7 generates an information signal such as a TV channel of a video signal and a recording date and time based on a user operation or the like. The VAUX data created by the signal processing microcomputer 8 and the above-mentioned framed data are combined. The signal is synthesized by the multiplexer 4, the error correction code is added by the error correction code adding circuit 5, recording modulation processing is performed by the channel encoder 6, and the result is output to the recording amplifier.
[0005]
Next, at the time of reproduction, the input reproduction data is subjected to waveform equalization and data clock reproduction by the reproduction circuit 9, recording and demodulation processing by the channel decoder 10, and error correction processing by the error correction circuit 11. Then, the VAUX data is extracted from the reproduced data by the demultiplexer 12 and sent to the signal processing microcomputer 8. The reproduced data is decomposed into frames by a deframing circuit 13, subjected to processing such as decoding of a variable length code, inverse quantization, and inverse DCT by a data compression / decoding circuit 14, and deshuffled using a shuffling memory 2. Is output. The extracted VAUX data is processed by the signal processing microcomputer 8 and the mode processing microcomputer 7 controls the reproduction mode.
In this manner, at the time of recording, VAUX data is added to the video digital data, and at the time of reproduction, the VAUX data extracted from the reproduced data is processed by the microcomputer to perform mode control.
[0006]
[Problems to be solved by the invention]
However, at the time of reproduction, since the reproduction mode of the data compression / decoding circuit 14 is processed by the microcomputer in response to the change of the reproduction mode added to the reproduction data, a time lag occurs until the mode change is determined.
FIG. 6 is a diagram showing a transition of a reproduction mode change in the conventional recording / reproduction device shown in FIG.
[0007]
As shown in the figure, the VAUX data extracted from the reproduction data is determined by the signal processing microcomputer 8 in the next frame, so it is delayed by one frame from the mode change of the reproduction data. Then, the next frame is transferred from the signal processing microcomputer 8 and the mode is determined by the mode processing microcomputer 7, which is delayed by one frame. Then, the mode output from the mode processing microcomputer 7 becomes valid in the data compression / decoding circuit 14 for the next frame. Therefore, the data compression / decoding is performed after a total of three frames delay from the mode change of the reproduction data. The mode of the circuit 14 changes.
[0008]
However, the deshuffling process performed by the data compression / decoding circuit 14 is performed in such a procedure that the reproduced data is once written in the shuffling memory 2 and the reproduced data is read out in a different order from the writing. Frame delayed. Therefore, the time lag between the mode change of the reproduction data and the mode change of the data compression / decoding circuit is three frames before and after deshuffling (when writing to the shuffling memory 2) and after deshuffling (when reading from the shuffling memory 2). The playback data has two frames.
During this time lag, the playback mode of the playback data and the playback mode of the data compression / decoding circuit 14 are different, and the playback video is disturbed. An example is shown below.
[0009]
FIG. 7 is a diagram showing a field configuration on an interlaced screen.
The video data is normally displayed in the position shown in the drawing on the screen in the frame reproduction mode in the order of the first field and the second field to form one screen (frame). As described above, in the frame reproduction mode, the data of each field is alternately read from the shuffling memory 2 as follows.
1st → 2nd → 1st → 2nd → 1st → 2nd
[0010]
However, when a normally recorded moving image is played back in slow motion, the same video data is displayed in a plurality of frames. However, since there is movement between the video in the first field and the video in the second field, the video blurs during playback. Will happen. In order to avoid this, at the time of slow reproduction, a field reproduction mode in which data of the first field or the second field is read twice from the shuffling memory 2 and displayed at both positions of the first field and the second field on the screen is used. And a method of averaging data of the first field and the second field.
[0011]
In the case of using the field reproduction mode, when transitioning from the normal reproduction to the slow reproduction, the reproduction mode changes from the frame reproduction mode to the first field reproduction mode or from the frame reproduction mode to the second field reproduction mode.
In this case, writing of data to the shuffling memory 2 is the same in the frame reproduction mode and the field reproduction mode, but the reading of data of each field from the shuffling memory 2 is as follows.
1st → 2nd → 1st → 1st → 1st → 1st
1st → 2nd → 2nd → 2nd → 2nd → 2nd
[0012]
Here, when the state in which the normally recorded moving image video is played back slowly is performed by a user operation, as shown in FIG. 6, the slow playback performed by the user operation is processed by the mode processing microcomputer 7 to determine the mode. Since the slow reproduction video data is sent according to the mode, the reproduction mode (frame reproduction / field reproduction) of the video data and the data compression / decoding circuit can be easily matched.
[0013]
However, there is a case where the mode is changed to the slow reproduction on the reproduction data side instead of the user operation. As an example, there is a case where reproduction data is transmitted by IEEE1394 communication. In this case, when the moving picture video normally recorded by the recording / reproducing apparatus on the transmitting side is slow-reproduced, the data of the slow-reproducing data is written in VAUX data so that the slow-reproducing can be discriminated and sent to the recording / reproducing apparatus on the receiving side. come. However, in the conventional recording / reproducing apparatus, even if the reproduced data is changed to the slow reproduction, the video is disturbed (blurred) because of the time lag until the switching from the frame reproduction mode to the field reproduction mode. As described above, since the writing of data to the shuffling memory 2 is the same between the frame reproduction mode and the field reproduction mode, the reproduction mode at the time of reading from the shuffling memory 2 affects the time lag. , Two frames, and the video is disturbed for two frames.
[0014]
Therefore, it is necessary to eliminate the time lag in order to eliminate the disturbance of the reproduced video when the reproduction mode in the VAUX data changes.
[0015]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides means for extracting VAUX data immediately before a data compression / decoding circuit, means for determining a reproduction mode from the extracted VAUX data, and data compression / decoding directly without a mode processing microcomputer. Means for directly controlling the reproduction mode of the decoding circuit, so that the data compression / decoding circuit is directly controlled by the extracted VAUX data, and the time lag between the reproduction mode change of the reproduction data and the reproduction mode change of the data compression / decoding circuit is provided. It is intended to realize a reduced recording and reproducing device.
[0016]
According to one aspect of the present invention, there is provided a recording and reproducing apparatus for recording and reproducing a digital video signal, a detecting means for extracting the VAUX data from the reproduced digital video signal from the extracted VAUX data and determining means for determining a reproduction mode A data compression / decoding means for compressing and decoding the reproduced video digital signal while deshuffling using a shuffling memory; and a control means for controlling a reproduction mode of the data compression / decoding means. In the recording / reproducing apparatus in which the reproduction mode is determined by the determination means when the detection mode is detected, and the control means controls the reproduction mode of the data compression / decoding means directly , before and after the detection means detects a change in the reproduction mode. In the case of the deshuffling, a format for writing reproduction data to the shuffling memory In the same case, when the read format from the shuffling memory is different, the read data written in the shuffle memory in the reproduction mode before the change is read from the shuffle memory in the reproduction mode after the change. In addition, the time lag between the mode change of the reproduction data and the mode change of the data compression / decoding means is eliminated, and the disturbance of the reproduced video at the time of the reproduction mode change is suppressed.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a block diagram showing one embodiment of the recording / reproducing apparatus of the present invention.
In the figure, reference numeral 15 denotes a VAUX data extraction / mode control circuit. The other configuration is the same as that of the conventional recording / reproducing apparatus shown in FIG. 5, and the same components are denoted by the same reference numerals. is there.
[0019]
Hereinafter, the operation of the present embodiment will be described.
First, at the time of recording, an input digital video signal is shuffled by a data compression encoding circuit 1 using a shuffling memory 2 to perform data compression encoding such as DCT (discrete cosine transform), quantization, and variable length encoding. The frame is processed by the framing circuit 3. The mode processing microcomputer 7 generates an information signal such as a TV channel of a video signal and a recording date and time based on a user operation or the like. The VAUX data created by the signal processing microcomputer 8 and the above-mentioned framed data are combined. The signal is synthesized by the multiplexer 4, the error correction code is added by the error correction code adding circuit 5, the recording modulation process is performed by the channel encoder 6, and the result is output to the recording amplifier.
[0020]
Next, at the time of reproduction, the input reproduction data is subjected to waveform equalization and data clock reproduction by the reproduction circuit 9, recording and demodulation processing by the channel decoder 10, and error correction processing by the error correction circuit 11. Then, the VAUX data is extracted from the reproduced data by the demultiplexer 12 and sent to the signal processing microcomputer 8. Here, VAUX data is added to the reproduction data. The reproduced data is decomposed into frames by a deframing circuit 13, subjected to processing such as decoding of a variable length code, inverse quantization, and inverse DCT by a data compression / decoding circuit 14, and subjected to deshuffling and output using a shuffling memory 2. Is done. At this time, the reproduction mode of the data compression / decoding circuit 14 is controlled by the VAUX data extraction / mode control circuit 15. The extracted VAUX data is processed by the signal processing microcomputer 8, and the mode processing microcomputer 7 controls the reproduction mode of the entire circuit.
The above is the outline of the operation of the embodiment of the present invention in which the data compression / decoding circuit is directly controlled by the extracted VAUX data. The operation of the VAUX data extraction / mode control circuit 15 which is a feature of the present invention will be further described. explain in detail.
[0021]
FIG. 2 is a configuration diagram of one track of video data to which an error correction code and VAUX data are added.
In the figure, 21 is a sync, 22 is an ID, 23 is video data, 24 is VAUX data, 25 is a remainder of VAUX data, 26 is pack header, 27 is pack data, 28 is inner parity, and 29 is outer parity. .
[0022]
As shown in the figure, the VAUX data 24 is divided into three syncs 21 in one track. 5 packs are separated from the head, and 15 packs are secured per sync 21. The remaining 25 bytes of VAUX data are not used. Therefore, the VAUX data 24 is composed of 45 packs per track. The first one byte of the five bytes of the VAUX data 24 is a pack header 26, which has a value unique to each pack. Then, various pack data 27 are stored in the remaining four bytes. The VAUX data 24 has 6 packs as a main area. In an even-numbered track including 0 in one video frame, 39 to 44 (in the VAUX data 24) are used. 0 to 5 (in the VAUX data 24) is the main area. In this main area, a source pack in which information such as a television broadcasting system and a television channel is recorded, a source control pack in which information such as a copyright bit and a recording mode are recorded, a recording date pack, and a recording time and minute A second pack etc. are stored. The contents of the main area are basically the same within one video frame.
[0023]
From the above, as an example of a method of extracting VAUX data, an even-numbered track is obtained from a sink including packs of 39 to 44, and an odd-numbered track is obtained from a sink including packs of 0 to 5 from a sink including packs of 0 to 5. This can be easily performed by detecting the target data in the pack header of the pack in which the target data is recorded. Here, examples of the VAUX data related to the reproduction mode include a source pack including information on a broadcast system and a recording system, and a source control pack including information on a trick mode and the like. Information on the change in the frame playback / field playback mode when the mode is changed to the slow playback on the playback data side exemplified in the description is included in the source control pack. Therefore, the VAUX data is extracted using the pack header 61h of the source control pack as a guide.
[0024]
FIG. 3 shows a data configuration diagram of the source control pack.
In the figure, 26 is a pack header, and 27 is pack data. The details of the pack data 27 of this pack are shown below.
PC1
CGMS: Copy generation management system COPY INPUT: Input source recording system COPY GEN: Copy generation SS: Source and recording status PC2
REC ST: Recording start point REC MODE: Recording mode (original / insert, etc.) DISP: Display selection PC3
FF: Frame / field reproduction flag FS: 1st / 2nd field flag FC: Frame change flag IL: Interlace flag ST: Still image flag SC: Still camera image flag BCSYS: Broadcast system PC4
GENRE CATEGORY: Genre classification
Among them, when the mode is changed from the normal reproduction to the slow reproduction on the reproduction data side, FF indicates the change from the frame reproduction mode to the field reproduction mode. Therefore, the data of this FF is extracted and the frame / field reproduction mode of the data compression / decoding circuit is controlled. Here, in order to faithfully follow the reproduction data side, it is necessary to see also the 1st / 2nd field flag indicated by FS. However, in order to eliminate the disturbance of the reproduction video, it is only necessary to control the frame / field reproduction mode with the FF at least. .
[0026]
Also, as an example of the method of determining the playback mode, the content of the main area is basically the same within one video frame, but reading may not be possible due to an error such as a scratch on the tape, so that it can be detected by the pack header. A method of using the last data in one video frame, or a method of selecting data by majority decision from the data of each track.
[0027]
FIG. 4 is a diagram showing the transition of the reproduction mode change in the recording / reproduction device according to the present invention.
As shown in this figure, the VAUX data extracted from the reproduction data is determined by the VAUX data extraction / mode control circuit 15 during the same frame. Since the mode output from the VAUX data extraction / mode control circuit 15 becomes valid in the data compression / decoding circuit 14 for the next frame, the data compression / decoding is delayed by one frame from the mode change of the reproduction data. The mode of the circuit 14 changes.
[0028]
However, since the reproduced data is delayed by one frame due to the deshuffling process, the time lag between the mode change of the reproduced data and the mode change of the data compression / decoding circuit 14 is one frame before the deshuffling (when writing to the shuffling memory 2). After the deshuffling (when reading from the shuffling memory 2), the reproduced data has no time lag.
[0029]
Here, as described above, in the frame reproduction mode and the field reproduction mode, since the writing of data to the shuffling memory 2 is the same, the reproduction mode at the time of reading from the shuffling memory 2 affects. No time lag.
Therefore, in the conventional recording and reproducing apparatus, when there is a change in the reproducing mode from the frame reproducing mode to the field reproducing mode, the disturbance of the video which has occurred during the time lag of two frames is caused by the recording and reproducing of the embodiment of the present invention. In the device, there is no time lag, so no disturbance occurs.
[0030]
As described above, when there is a change in the playback mode during the playback, the mode is quickly changed to suppress the disturbance of the playback video.
[0031]
【The invention's effect】
According to the present invention, by detecting the change in the reproduction mode and quickly controlling the mode of the data compression / decoding circuit, it is possible to suppress the disturbance of the reproduced video at the time of the change in the reproduction mode. It is possible to realize a recording and reproducing apparatus with improved image quality.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a recording / reproducing apparatus according to the present invention.
FIG. 2 is a diagram showing a configuration of video data.
FIG. 3 is a diagram showing a data configuration of a source control pack.
FIG. 4 is a diagram showing a change in a reproduction mode change in the recording / reproduction device of the present invention.
FIG. 5 is a block diagram showing a conventional recording / reproducing apparatus.
FIG. 6 is a diagram showing a change in a reproduction mode change in a conventional recording / reproduction device.
FIG. 7 is a diagram showing a field configuration on a screen.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Data compression encoding circuit, 2 ... Shuffling memory, 3 ... Framing circuit, 4 ... Multiplexer (MUX), 5 ... Error correction code addition circuit, 6 ... Channel encoder, 7 ... Mode processing microcomputer, 8 ... Signal processing microcomputer , 9 ... reproduction circuit, 10 ... channel decoder, 11 ... error correction circuit, 12 ... demultiplexer (DMUX), 13 ... deframing circuit, 14 ... data compression / decoding circuit, 15 ... VAUX data extraction / mode control circuit, 21 ... Sync, 22 ... ID, 23 ... Video data, 24 ... VAUX data, 25 ... Remainder of VAUX data, 26 ... Pack header, 27 ... Pack data, 28 ... Inner parity, 29 ... Outer parity.

Claims (1)

A recording and reproducing apparatus for recording and reproducing a digital video signal, a detecting means for extracting the VAUX data from the reproduced digital video signal, extracting a VAUX determining means for determining a playback mode from the data, reproduced digital video signal to shuffling memory And a control means for controlling a reproduction mode of the data compression / decoding means, wherein a change in the reproduction mode from the VAUX data extracted by the detection means is provided. When the detection mode is detected, a change in the reproduction mode is detected by the detection means in the recording / reproduction device that determines the reproduction mode by the determination means and directly controls the reproduction mode of the data compression / decoding means by the control means . Before and after, at the time of the deshuffling, the reproduction data is stored in the shuffling memory. When the writing format is the same and the reading format from the shuffling memory is different, the reproduction data written to the shuffling memory in the reproduction mode before the change is read from the shuffling memory in the reproduction mode after the change. A recording / reproducing apparatus which eliminates a time lag between a mode change of reproduced data and a mode change of the data compression / decoding means, thereby suppressing disturbance of a reproduced video when the reproduction mode changes .

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