JP3906014B2 - RECORDING MEDIUM DRIVE DEVICE HAVING SYNCHRONIZATION INFORMATION PROCESSING FUNCTION WITH RECORDING MEDIUM - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to, for example, a recording device for a DVD (digital video disc), a driving device for a recording medium used in a reproducing device, and the recording medium such as a disc and a memory.
[0002]
[Prior art]
There is a method of realizing a stereoscopic video playback device by simultaneously playing back two laser disk (LD) playback devices so that one device plays the left-eye video and the other device plays the right-eye video. is there. In this stereoscopic video playback device, the left-eye video signal and the right-eye video signal obtained from the two playback devices are synchronized in units of frames.
[0003]
Also, using multiple projection TV devices, assigning a split screen that divides the image for one screen to each of the multiple projection TV devices, constructing it as a single monitor as a whole, and displaying a large screen on the screen There is a so-called video wall. At this time, each projection television apparatus needs to reproduce the respective reproduced videos in synchronization with each other.
[0004]
[Problems to be solved by the invention]
As described above, in a stereoscopic video playback device and a video wall, it is necessary for a plurality of video playback devices to play back video signals in synchronization with each other.
[0005]
By the way, in recent years, a large-capacity digital video disc (so-called DVD) having a configuration in which two substrates are bonded with a diameter of 12 cm has been developed. Of course, this DVD is also applicable to the above-described stereoscopic video reproduction apparatus and video wall.
[0006]
However, in the case of DVD, because of the video compression method, it is difficult to synchronize video signals reproduced from a plurality of playback devices to each other in units of frames, and it is difficult to apply them to stereoscopic video playback devices and video walls. It is possible. This is strictly specified on a frame-by-frame basis due to the fact that compressed images in the MPEG2 system must be decoded and that there is a delay time (including the performance of the current MPEG decoder) that the microcomputer controls the MPEG decoder. This is because it is difficult to start playback. Even when the video synchronization signals of the two DVD players are actually synchronized, the reproduction always involves an error of 1 to 2 frames.
[0007]
Therefore, in order to solve the above-described problem, the present invention records synchronization information for frame synchronization (different from the blanking period) on a medium, and a playback apparatus is equipped with a synchronization processing function, thereby It is an object of the present invention to provide a recording medium driving apparatus having a synchronous information processing function and a recording medium in which a video signal reproduced by the reproduction apparatus can perform frame synchronous reproduction between desired frames.
[0008]
Specifically, the overall system is configured to perform playback operation of a plurality of playback devices, so that playback can be started automatically with perfect frame synchronization.
[0009]
Also, even if there is a frame shift during playback (such as missing frames due to audio master control), the playback device automatically detects the shift, corrects the shift, and synchronizes as if nothing had happened. It is a system that keeps and continues playback
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, in a recording medium, synchronization information for obtaining frame (or field) synchronization is recorded in an area of a recorded compressed main video.
[0011]
  The present invention is also reproduced from a recording medium.Compressed main video areaFrame (field) synchronization information is extracted fromObtained from a circuit that performs error correction processing on the synchronization information sequence, a difference detection circuit that obtains difference information between the synchronization information subjected to the error correction processing and synchronization information from another device, and the difference detection circuit And a controller that outputs a control signal for controlling a delay time of the video signal of the own device or the video signal of the other device according to the difference information.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0013]
FIG. 1 shows an overall schematic configuration of a DVD playback apparatus as an example to which the present invention is applied. The optical disk 11 is rotationally driven by a disk motor 12. Information recorded on the disk 11 is optically read by the pickup 13. The read information is converted from light to an electrical signal, amplified by the amplifier 14, and input to the signal processing unit 15.
[0014]
The signal processing unit 15 performs processing such as data demodulation and error correction. The video information is guided to the video processing unit 16, the sub-picture information is guided to the sub-picture processing unit 17, and the audio information is guided to the audio processing unit 18. . The video processing unit 16 decodes the projection information compressed by the MPEG system, and the decoded video information is encoded into a display-side video system (NTSC system, PAL system, high-definition television signal system, etc.). And guided to the synthesizer 19.
[0015]
If there is subtitle information such as a movie, the sub-picture processing unit 17 decodes it and supplies the decoded sub-picture to the synthesizer 19. The output of the synthesizer 19 is led to the output terminal 20. The audio information decoded by the audio processing unit 18 is derived to each channel output unit 21.
[0016]
A servo signal processing unit 31 uses the reproduction information in the signal processing unit 15 to generate, for example, focus error information, tracking error information, rotation speed information, and the like. Focus error information and tracking error information are supplied to the pickup drive circuit 32. Thereby, the tracking and focus of the pickup 13 are controlled. The rotational speed information is input to the motor drive circuit 33. Thereby, the rotational speed of the disk 11 is controlled via the disk motor 12.
[0017]
The system control unit 35 controls the operation of the entire playback apparatus. In response to operation information from the operation unit 36, for example, a playback state, a pause state, a stop state, a repeated playback state, and the like can be executed. it can. It is also possible to control sub-picture synthesis or non-synthesis, sub-picture selection (English, Japanese, etc.), and audio channel selection. The system control unit 35 can also switch and set the output video system (NTSC system, PAL system, high-definition television signal system, etc.).
[0018]
Here, the apparatus according to the present invention also has a function and means for obtaining frame synchronization with the playback video signal of another device (second DVD playback apparatus).
[0019]
For this purpose, the system control unit 35 is provided with a synchronization information input unit 37 from the master device and a synchronization information output unit 38 for giving synchronization information from the present device to another device (slave device).
[0020]
FIG. 2 shows an example in which a stereoscopic video display device is constructed using a master device 41 and a slave device 42. The master device 41 reproduces the disc on which the video for the left eye is recorded, and the slave device 42 reproduces the disc on which the video for the right eye is recorded. The mutual devices are connected via a synchronization information input / output unit. The video signal reproduced by the master device 41 is guided to the left video output projection unit of the projector 43, and the video signal reproduced by the slave device 42 is guided to the right video output projection unit of the projector 43. Images projected from the projection units are projected on the screen 44. Here, the viewer can observe stereoscopic images through, for example, polarized glasses.
[0021]
FIG. 3 is a diagram showing a part particularly important for the present invention extracted from the video processing unit 16 and the system control unit 35.
[0022]
The apparatus of the present invention can take either a master player or a slave player. Video information from the signal processing unit 15 is decoded by the MPEG decoder 51 via the input terminal 100. The video signal decoded by the MPEG decoder 51 is input to the selector 54 and also input to the frame memory 52, and the output of the frame memory 51 is further input to the frame memory 53. The output of the frame memory 52 and the output of the frame memory 53 are input to the selector 54.
[0023]
The selector 54 selects any input based on a control signal from a player controller 58 to be described later, and supplies the selected output to the video encoder 60. The output of the video encoder 60 is led to the output terminal 101.
[0024]
The output of the MPEG decoder 51 is input to the frame synchronization signal detection circuit 55. The detected frame synchronization signal is error-corrected by the synchronization error correction circuit 56, and its output is input to the frame difference detection circuit 57.
[0025]
The frame synchronization signal is devised in the present invention, and is a signal in which regular values are arranged in the time axis direction as will be described later. For example, a signal having periodicity is inserted in 23 lines every frame. The frame difference detection circuit 57 is a circuit that detects how much difference is generated between the synchronization signal from the master (master player) and the synchronization signal from the slave player. Thereby, it is possible to detect a synchronization shift between the reproduction signals of the master player and the slave player. Frame information from the slave player is taken in via the input terminal 102.
[0026]
The synchronization information is not limited to 23 lines, but may be a predetermined line or area preceding the frame.
[0027]
Difference information from the frame difference detection circuit 57 is input to the player controller 58. The player controller 58 outputs select information k to a similar player controller provided in the slave player according to the difference information. This selection information k is used to correct the deviation between the master player and the slave player, and is selection information for the slave player to select the output of the frame memory in accordance with the inter-frame difference amount. This select information k is output from the output terminal 103. The operation of selecting the frame memory based on the selection information k is preferably performed, for example, in the horizontal blanking period immediately after detecting the synchronization information.
[0028]
In the output selection of the frame memory based on the selection information of the output terminal 103 described above, when there is a deviation that cannot be absorbed, the player controller 58 outputs the slave player control signal l and also outputs the master player control signal i. To do. Then, both the master player and the slave player are set in a paused state. The master player is put into a pause state by the system control microcomputer 61.
[0029]
If the slave player is delayed in the (−) direction, the slave player is set to the “frame advance” operation mode, or the master player is set to the “frame return” operation mode. Conversely, if the slave player is moving in the (+) direction, the slave player is set to the “frame return” operation mode, or the master player is set to the “frame advance” operation mode. In this way, feedback control is performed so that the difference value from the frame difference detection circuit 57 becomes “0”. When the difference value becomes “0”, normal playback of both players is resumed.
[0030]
The system control microcomputer 61 controls the player's pause, frame advance, frame return, and operation mode. The frame memory controller 59 performs data writing / reading control of the frame memories 52 and 53.
[0031]
An external synchronization PLL circuit 62 generates a horizontal synchronization signal and a vertical synchronization signal from the regenerated clock. Further, the generated horizontal synchronizing signal (H) and vertical synchronizing signal (V) are output from the terminal 105. Furthermore, a horizontal synchronization signal and a vertical synchronization signal generated by an external device (for example, another DVD player) can be taken in from the terminal 115, and the entire apparatus can be synchronized with the synchronization signal.
[0032]
In the above description, the example in which the player functions as a master player has been described, but the player can also function as a slave player.
[0033]
When this player works as a slave player, the player controller 58 is given selection information (terminal 113) from the master player and a slave player control signal (terminal 114) from the master player.
[0034]
When the player functions as a slave player, the frame information of the player is output from the output terminal 112. Furthermore, the select information k is output from the output terminal 103 when the player functions as a master, but when the player functions as a slave, select information from the master player is input from the input terminal 113. .
[0035]
As described above, this player can adjust the output time of the decoded video signal by about three frames in units of frames in this embodiment by controlling the selection state of the selector 54. Thereby, frame synchronization between the master player and the slave player can be obtained.
[0036]
FIG. 4 is a simple flowchart showing the frame synchronization operation of the player. When the player starts reproduction (step A1), the reproduction start is automatically detected when the reproduction is started. By determining whether or not the frame synchronization signal is incremented, it is determined whether or not the reproduction is started (step A2).
[0037]
If playback is in progress, a frame difference between the master player and the slave player is detected (step A3). As a result of detecting the frame difference, if it is in a synchronous state (including cases where it can be handled by selection of the frame memory), the process ends. If it is in an asynchronous state, it is determined whether or not the number of retries exceeds n (step A4, A5). If the number of retries exceeds n, the players are stopped all at once and a warning is given that an abnormal state has occurred (step A6).
[0038]
If the number of retries is less than or equal to n, the slave and the master player are put into a pause state all at once (step A7), the frame difference described above is detected, and then the frame difference is adjusted (steps A8 and A9).
[0039]
The adjustment of the frame difference is the above-described frame advance, frame return, or the like. When the synchronization state is reached, the slave and the master player move to the playback state all at once (step A10), and then return to step A4.
[0040]
The present invention is not limited to the above method. In FIG. 4, when the number of retries is n or less, a simultaneous pause is performed. However, the present invention is not limited to this, and it is also possible to perform synchronization while maintaining the master player and the slave player at the same time as shown in FIG.
[0041]
That is, as shown in FIG. 5, if it is determined in step A4 that the frame memories 52 and 53 alone cannot cope, the process proceeds to step A11. In this step A11, both players are maintained in the reproduction state, and the player on the advance side is set to the pause mode and the reproduction mode for each frame, and this is repeated a plurality of times. The late player receives the frame information from the advance player, and the frame difference detection circuit 57 detects the difference. If the frames match, both players return to step A2. If the frames do not match, the process proceeds to step A11. Note that steps A1 to A4 are the same as those in the previous embodiment, and a description thereof will be omitted.
[0042]
This method has an advantage that it is less likely to feel the synchronization operation for human vision than the simultaneous pose. Further, the present invention is not limited to the above method.
[0043]
FIG. 6 shows still another embodiment of the present invention. That is, if it is determined in step A4 that the frame memories 52 and 53 alone cannot cope, the process proceeds to step A21. In this step A21, both players are maintained in the reproduction state, and the leading player is temporarily stopped (that is, the still reproduction state is set). During this time, the delayed player continues to play. Then, a difference in frame synchronization between both players is detected to determine whether or not the frames match. If the frames do not match, the process returns to step A21. If the frames match, the process proceeds to step A2. Note that steps A1 to A4 are the same as those in the previous embodiment, and a description thereof will be omitted.
[0044]
If it is determined that the frame 52 or 53 alone cannot be used, and if an external control device (such as a personal computer) for controlling the system is connected to the player, the system control microcomputer 61 sends an error to the external control device. Output information. As a result, the external control device gives effective control information to, for example, a device that sends the next video information to the player or a device that records the player output, and is unnecessary when the image synchronization is disturbed. Output and unnecessary recording can be prevented.
[0045]
The present invention is not limited to the above embodiment.
[0046]
FIG. 7 shows still another embodiment. The steps up to step A6 are the same as those in the embodiment of FIG. In step A5, when the number of retries is n or less, the advancing player is put into a pause state for one frame (step B1). Next, the advancing player is set in the playback state again (step B2), and the frame difference between both players is detected (step B3). Then, it is determined whether the frames match (step B4). If they match, the process returns to step A2, and if they do not match, the process returns to step B1.
[0047]
FIG. 8 shows still another embodiment. The steps up to step A6 are the same as those in the embodiment of FIG. In step A5, when the number of retries is n or less, the advancing player is put in a pause state (step C1). Next, the difference between the frames of both players is detected (step C1). Then, it is determined whether or not the frames match (step C3). If they match, the player on the advance side is put into a playback state ((step C4), and the process returns to step A2. If they do not match, the process returns to step C2. As a result, the playback of the player on the lag side proceeds, and eventually the difference between frames becomes zero.
[0048]
The present invention is not limited to the above-described embodiment when taking measures against frame matching.
[0049]
FIG. 9 shows an example in which the frame synchronization signal is regenerated (regenerated) by a counter inside the system with reference to the frame synchronization signal on the 23rd line, and the synchronization determination processing is strengthened against disturbance.
[0050]
That is, when playback is started (step D1), the 23rd line synchronization signal is referred to (step D2). Next, synchronization adjustment processing is performed (step D3). There are several methods for this synchronization matching process as described above. Next, reference is made to the internally generated frame synchronization signal (step D4). The internally generated synchronization signal is a synchronization signal obtained from a counter that obtains a count output of the vertical period (frame period) inside the system so as to be synchronized (matched) with the frame synchronization signal multiplexed on the 23rd line. . The value of the internally generated synchronization signal is synchronized by loading the value of the frame synchronization signal multiplexed on the 23rd line as an initial value into the counter. Thereafter, the frame synchronization state between both players is monitored using this internally generated synchronization signal.
[0051]
Here, it continues to monitor whether there is an input of external operation information (fast forward, top return, pause, pause, pause, etc.) or whether a synchronization loss occurs. When the external operation information is input, the loss of synchronization returns to step D2 and is executed again from the process of referring to the synchronization signal on the 23rd line. While the frame match is monitored with reference to the internal frame synchronization signal, the internal synchronization counter is not loaded with the frame synchronization signal value of the 23rd line.
[0052]
FIG. 10 shows an example of conditions for performing the above-described loading. This process is provided, for example, between steps D3 and D4 in FIG. That is, referring to the synchronization signal of the 23rd line, it is determined whether or not the synchronization signal between 3 frames has been normally incremented (step D11), and when the synchronization signal is normally incremented for 3 frames, The frame synchronization signal value is loaded into a counter that generates an internal synchronization signal (step D12).
[0053]
Here, the interframe difference detection circuit summarizes the condition A for referring to the internally generated frame synchronization signal and the condition B for referring to the frame synchronization signal on the 23rd line.
[0054]
Condition A: When playback is started with the frame sync signals of both players matching after playback has started.
[0055]
Condition B: When the frame synchronization of both players is not “match”, and when the synchronization is synchronized. Also, when the playback state of the player changes due to external factors (key input, command input, etc.). Furthermore, when the correction function is turned off by selecting a dip switch (DIP_SW) or the like. That is, for example, when the user performs a forced switch operation so as to fix the frame synchronization signal to be referenced to the synchronization signal of the 23rd line.
[0056]
Next, the frame synchronization signal will be described.
[0057]
FIG. 11A shows a frame of the decoded video signal in the time axis direction, and a synchronization signal is multiplexed on the 23rd horizontal line belonging to the vertical blanking period. In the digital video signal (ITU-R656), chroma (Cr, Cb) signals and luminance (Y) signals are alternately arranged in 23 lines as shown in FIG.
[0058]
Here, in the present invention, a frame synchronization signal is inserted into these 23 lines. As an example, the Y signal level changes from 16 to 235, and the Y signal is repeated. When this repetition is shown in the drawing, the level changes as shown in FIG. The chroma signal is fixed at 128.
[0059]
FIG. 12 shows the error correction principle of the synchronization error correction circuit 56 that performs error correction of the frame synchronization signal.
[0060]
If there is lost data A now, the value is estimated from the preceding and following lines. Thereafter, statistics of the Y value of the same line are taken, and the Y value is used as a frame synchronization signal. The same applies when there is lost data B shown in the figure.
[0061]
Now, when there is a lot of data (color data) such as lost data C, or when there is a large variation in the statistical value of Y data, it is further determined that a certain threshold is set and the frame synchronization signal has many errors. In such a case, the synchronization signal is not referred to. In this case, a pseudo synchronization signal is set from the value of the free run counter in the system, and the pseudo synchronization signal is referred to.
[0062]
The frame synchronization signal is not limited to the above embodiment.
[0063]
FIG. 13 shows another embodiment of the frame synchronization signal. This synchronization signal is a horizontal line of 100% white, and the horizontal line has a length L changed in units of frames, and this change is repeated. FIG. 13A shows how the length of the white horizontal line 800 changes for each frame, and FIG. 13B shows how this change is repeated.
[0064]
Here, the unit of change in length for each frame is preferably, for example, an 8-pixel unit in view of image compression technology. This is because a discrete cosine transform (DCT) macroblock unit (MPEG compression method unit) is 8 × 8 pixels. Specifically, the length was varied by incrementing 8 to 720 pixels in 8 pixel steps.
[0065]
The unit of change in length for each frame is easier to process in the unit of pixel block used in image compression. In addition, encoding is preferably performed using a variable bit rate (VBR) system rather than a constant bit rate (CBR) system, and data during reproduction is stable. Furthermore, in this embodiment, the cycle of the synchronization signal is about 3 seconds, and the length of the synchronization signal changes within the range of 8 to 720 pixels in units of 8 pixels. The sync signal was successfully extracted by setting the sync signal to white line (Y = 235) and black (Y = 16) and the threshold to 128.
[0066]
As described above, according to the present invention, the reproduction outputs of a plurality of players can be synchronized in units of frames or fields. Since the synchronization information serving as the reference for synchronization is recorded in the main video area of the disc in units of frames or fields, there is a one-to-one relationship between the frame or field image and the synchronization information. Since DVD employs MPEG compression, superimposing a synchronization signal on the main video area results in lossy compression and may cause errors in the synchronization information. Therefore, the synchronization information has regularity (repetition pattern) in the time direction, the number of synchronization information per frame (number of samples) is increased to increase the certainty (probability) of the information, and further error correction processing is performed. Loss synchronization information is restored.
[0067]
In addition, as a region where the synchronization signal is superimposed on the main video, a region close to blanking that is difficult for the viewer to see is used. In addition, the expression of the synchronization signal suppresses the amount of change in the signal level when only the luminance (Y) signal is superimposed or superimposed on the color (C) signal so as not to stand out.
[0068]
Further, as a representation of a synchronization signal with few errors with respect to MPEG image compression, it is possible to identify by a pixel unit location without using the change in luminance signal level / color difference signal level (FIG. 14). Also, when video is output from the frame memory to the line where the sync signal is inserted, the video data lost due to the sync signal is restored by the correlation between the previous and next lines, or the data is replaced by black data, etc. It is also possible not to display the signal video.
[0069]
The above apparatus (DVD player) can provide a system that has a plurality of frame memories (may be field memories) and absorbs the difference of the synchronization signals by selectively switching the output stage of each frame memory. . Multiple DVD players, when a frame difference exceeding the number of stages in the frame memory occurs, pauses the players all at once (PAUSE), and performs a frame unit such as “frame advance / frame return” for players with large frame deviations. It is equipped with a feedback control loop that performs fine adjustment and replays all at once.
[0070]
In addition, for an image output of a DVD player having a system in which video and audio synchronization processing uses audio as a master (reference), an output that is as close to the forefront of the frame memory as possible is selected. This is to increase one margin in order to instantaneously absorb the frame delay of the image due to the projection synchronization processing that occurs unexpectedly during reproduction.
[0071]
The system described above is a system that absorbs frame errors with other players by delaying video data in units of frames, so that video is output later than audio. If the system can delay-adjust the audio output in units of frames within the MPEG decoder, there is no problem, but if the system cannot be adjusted, the digital output (S / PDIF) of the audio is used, and this is converted to the frame by the shift register. Delay by delay.
[0072]
In the above description, it is assumed that a frame synchronization signal for obtaining frame synchronization is recorded in advance on the recording medium. It has been described that a plurality of players can obtain frame synchronization during reproduction. However, the present invention is not limited to such an embodiment. Even in a recording apparatus or an editing apparatus, a synchronization signal recording processing circuit for recording a synchronization signal on, for example, 23 lines of the main video signal is provided. Of course, it is also good. In the above description, two players have been described. Of course, the number of players may be increased.
[0073]
In addition to the 3D display system, the present invention can be applied to a plurality of playback devices simultaneously, and each playback device plays back a disc containing scenes and the like taken at different angles simultaneously. It can also be applied to systems that display video on the screen.
[0074]
In the apparatus shown in FIG. 3, two stages of frame memories for delaying for frame synchronization are connected. Therefore, a 0 frame delay output, a 1 frame delay output, and a 2 frame delay output can be obtained. While performing the delay adjustment here, for example, the master player may be in a 1-frame delay state and the slave player may be in a 2-frame delay state. In such a relationship, the state is recognized by the control microcomputer 61 of the master player, for example. In this case, adjustment is made so that the master player selects the 0-frame delay output and the slave player selects the 1-frame delay output all at once. Actually, the pause → play operation is processed in a pseudo high speed.
[0075]
In order for the master player to operate as described above, when the output of the last stage, that is, the slave player selects the two-frame delay state, the slave player informs the master player of the selected state to the master player. It starts from that. The adjustment is made to be one frame in order to minimize the interruption of the sound when the sound is output from the player executing this function (the sound is naturally muted during the pause).
[0076]
Furthermore, while the synchronization is being corrected, there are cases where both the master player and the slave player have selected the 2-frame delayed output. Also in such a case, the above-described pause-> play operation is performed, and the master player and the slave player are switched so as to select the one-frame delayed output. Then, after a certain period of time during which the audio output is stable, the pause → play operation is performed again, and the master player and the slave player are switched so as to select the 0-frame delayed output this time. As a result, the first delay output is selected as much as possible.
[0077]
The synchronization signal in the present invention is not limited to the above embodiment.
[0078]
For the frame synchronization signal superimposed on the 23rd line, an identification method using a digital code is conceivable in addition to the above-described analog amount identification method. As a simple method, there is a method of superimposing binary data as it is on the 23rd line. As the error detection function, a parity check function can be added.
[0079]
FIG. 15A shows an example in which frame synchronization information “10101101” as data is expressed by the 23rd line, for example. 64 pixels are assigned to 1 bit, and Y level = 16 and C level = 128 are assigned as the code “0”. As the code “1”, Y level = 235 and C level = 128 are assigned. A parity bit is assigned to the last bit.
[0080]
Based on the above rules, the data as the synchronization information is varied from 0 to 255 for each frame, and when this is repeated, the change characteristics as shown in FIG. 15B are obtained.
[0081]
If the statistics of the pixel data for 64 pixels are taken, it can be determined whether this one bit is “1” or “0”. When a data error is detected by the parity bit, the system does not refer to the frame synchronization signal data, and infers a regularly incremented value from the previous frame synchronization signal, and determines this value. Adopt it.
[0082]
The data representing the code uses 64 pixels (8 × 8), but the data width is not limited to this. As the data width becomes wider, data destruction (error) due to MPEG compression is reduced. However, if the data width is too wide, the frame identification range is reduced, so the above width is preferable.
[0083]
【The invention's effect】
As described above, according to the present invention, the synchronization information for frame synchronization (different from the blanking period) is recorded on the medium, and the playback device is equipped with a synchronization processing function, so that a plurality of units are recorded. Frame-synchronized reproduction is obtained between desired frames of the video signal reproduced by the reproduction apparatus.
[Brief description of the drawings]
FIG. 1 is a diagram showing the configuration of a disc recording / reproducing apparatus to which the invention is applied.
FIG. 2 is a configuration explanatory diagram of a stereoscopic video display device.
FIG. 3 is a configuration diagram showing a main part of the apparatus according to the present invention.
FIG. 4 is a flowchart shown for explaining an operation example of the apparatus according to the present invention.
FIG. 5 is a flowchart shown for explaining another operation example of the apparatus according to the present invention;
FIG. 6 is a flowchart for explaining another example of the operation of the apparatus according to the present invention.
FIG. 7 is a flowchart shown for explaining another operation example of the apparatus according to the present invention.
FIG. 8 is a flowchart shown for explaining another operation example of the apparatus according to the present invention.
FIG. 9 is a flowchart shown for explaining still another operation example of the apparatus according to the present invention.
FIG. 10 is a flowchart shown for explaining another operation example of the apparatus according to the present invention.
FIG. 11 is an explanatory diagram of a synchronization signal provided in a video frame in the recording medium according to the present invention.
12 is an explanatory diagram showing a state of conversion of the synchronization signal of FIG. 11;
FIG. 13 is an explanatory diagram for explaining error correction of a synchronization signal according to the present invention.
FIG. 14 is a diagram showing another embodiment of a synchronization signal according to the present invention.
FIG. 15 is a diagram showing still another embodiment of a synchronization signal according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Disc, 12 ... Disc motor, 13 ... Pickup, 14 ... Amplifier, 15 ... Signal processing unit, 16 ... Video processing unit, 17 ... Sub picture processing unit, 18 ... Audio processing unit, 19 ... Synthesizer, 31 ... Servo Signal processing section 32... Pickup drive circuit 33. Motor drive circuit 35. System control section 36. Operation section 51. MPEG decoder 2, 53. 56 ... Synchronization error correction circuit, 57 ... Frame difference detection circuit, 58 ... Player controller, 60 ... Video encoder, 61 ... System control microcomputer, 62 ... PLL circuit for external synchronization.

Claims (10)

  A recording medium in which synchronization information for obtaining frame (or field) synchronization is recorded in a compressed main video area recorded on a disc.   The compressed main video is a compressed video according to the MPEG system, and the synchronization information is superimposed on a predetermined line or area preceding in the frame, changes in units of frames, and repeats the changes in units of a plurality of frames. 2. The recording medium according to claim 1, wherein The compressed main image to be recorded on the recording medium body, a recording medium drive having a synchronous information processing function having a processing function of inserting synchronization information for frame synchronization. A circuit that extracts frame (field) synchronization information from the compressed main video area reproduced from the recording medium, and performs error correction processing on the synchronization information sequence;
A difference detection circuit for obtaining difference information between the synchronization information subjected to the error correction processing and the synchronization information from another device;
A controller that outputs a control signal for controlling a delay time of the video signal of the own device or the video signal of the other device according to the difference information obtained from the difference detection circuit. Recording medium drive apparatus having a synchronous information processing function.   5. The recording medium driving device according to claim 4, wherein the controller controls the delay amount based on the control signal during a horizontal blanking period immediately after detecting the frame synchronization information.   When the difference information is difference information that cannot be compensated for by the delay amount owned by the own device or the delay amount owned by the other device, a control signal for suspension is sent to other devices including the own device. 5. The recording medium driving apparatus having a synchronous information processing function according to claim 4, further comprising means for outputting. If the difference information is difference information that cannot be compensated for by the delay amount owned by the own device or the delay amount owned by the other device, a control signal for suspension is sent to other devices including the own device. Further comprising means for outputting,
5. The recording medium driving apparatus having a synchronous information processing function according to claim 4, further comprising means for providing information indicating synchronization mismatch to an external control device connected thereto. If the difference information is difference information that cannot be compensated for by the delay amount owned by the own device or the delay amount owned by the other device, a control signal for suspension is sent to other devices including the own device. Further comprising means for outputting,
In addition, the self-device or other device performs frame-by-frame frame playback or frame-back playback in the direction in which the difference information becomes zero, and when the difference information becomes zero, playback is started all at once. 5. The recording medium driving apparatus according to claim 4, wherein when the difference information is generated, the difference information is compensated by a delay amount owned by the own device or a delay amount owned by another device. If the difference information is differential information that cannot be compensated for by the delay amount owned by the own device or the delay amount owned by the other device, for other devices including the own device,
Based on a device that is delayed in reproduction, a device that periodically generates a frame-by-frame pause state for the device that is proceeding in reproduction multiple times and controls the difference information to zero. 5. The recording medium driving device according to claim 4, wherein: If the difference information is differential information that cannot be compensated for by the delay amount owned by the own device or the delay amount owned by the other device, for other devices including the own device,
Means that sets the device on which playback is progressing to a paused state with the device on which playback is delayed as a reference, and sets the device on which playback is progressing to the playback state when the difference information becomes zero 5. The recording medium driving device according to claim 4, further comprising:

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