Abstract:
A recording/reproducing apparatus by which optimum playback pictures can be produced eve in case of parallel recording/reproduction. A storage unit  123  transiently stores video signals obtained from an overwrite type disc-shaped recording medium  102 . A signal processing unit  122  decodes video signals stored in the storage unit  123 . A holding unit  124  holds video signals decoded by the signal decoding unit  122 . A control unit  101  performs control of the entire apparatus and also performs control for address management and data transfer of the disc-shaped recording medium  102  so that, if the apparatus is set to a mode of performing a playback operation while the recording operation is going on, the storage means  123  stores plural fields of the video signals and the holding unit  124  interpolates the video signals.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to a recording/reproducing apparatus for recording and reproducing video signals and speech signals on or from an optical disc or a magnetic disc as a overwrite type disc-shaped recording medium. 
     Recently, in a recording/reproducing apparatus for recording and reproducing video signals and speech signals on or from an optical disc or a magnetic disc as a overwrite type disc-shaped recording medium, a technique of perpetually recording live broadcast of, for example, a television program at all times in order to retrogressively view a sole scene which has been overlooked and which it is desired to re-view by the viewer. 
     Such a recording/reproducing apparatus includes, as shown in FIG. 1, an analog/digital (A/D) converter  311  for digitizing picture signals entering an input terminal I 3a , and a synchronization separating circuit  310  for extracting vertical synchronization signal of the picture signal entering the input terminal I 3a . The recording/reproducing apparatus also includes a compression circuit  312  for encoding picture data from an A/D converter  311  in synchronism with vertical synchronization signal from the synchronization separating circuit  310  and a first-in first-out buffer (FIFO)  313  for storing the picture data from the A/D converter  311 . The FIFO buffer is referred to herein as a buffer for video recording. The recording/reproducing apparatus also includes an A/D converter  331  for digitizing speech signals entering an input terminal I 3c  and a compression circuit  332  for encoding speech data from the A/D converter  331  in synchronism with a vertical synchronization signal from the synchronization separating circuit  310 . The recording/reproducing apparatus also includes a FIFO buffer  333  for storing speech data from the compression circuit  332 . The FIFO buffer  333  is referred to herein as a buffer for speech recording. The recording/reproducing apparatus further includes a disc drive  303  for recording video data from speech data from the FIFO  313  for storing the picture data and the speech data from the FIFO buffer  333  for storing speech data on a overwrite type disc  302  in accordance with a pre-set format and for reproducing the speech data and the video data recorded on the disc  302 . 
     The input terminals I 3a  and I 3c  are connected to, for example, a tuner, not shown, configured for receiving live broadcast. 
     The recording/reproducing apparatus  300  also includes a FIFO buffer for storing speech data obtained by the disc drive  303  and an expansion circuit  342  for decoding the speech data from the FIFO buffer  343  in synchronism with the vertical synchronization signals from the synchronization separation signal  310 . The FIFO buffer  343  is referred to herein as a buffer for speech reproduction. The recording/reproducing apparatus  300  also includes digital analog (D/A) converter  341  for converting speech data from the expansion circuit  342  into analog data for outputting at an output terminal I 3d , and a FIFO buffer  323  for storing video data obtained from the disc drive  303 . The FIFO buffer  323  is referred to herein as a buffer for video reproduction. The recording/reproducing apparatus  300  further includes an expansion circuit  322  for decoding video data from the expansion circuit  322  and a D/A converter  321  for converting the video data from the expansion circuit  322  into analog data for outputting at an output terminal I 3b . The speech data stored in the FIFO buffer for speech reproduction  343  is also supplied to the disc drive  303 . 
     The output terminals I 3b  and I 3d  are connected to a monitor not shown, configured for displaying and outputting a picture derived from the video signals supplied thereto via output terminal I 3b  and for outputting the speech derived from the speech signals supplied thereto from a speaker, not shown, via output terminal I 3d . 
     The recording/reproducing apparatus  300  also includes a system controller  301  for controlling an output of the buffer for video recording  313  to the disc drive  303 , an output of the buffer for speech recording  333  to the disc drive  303 , an output of the buffer for speech reproduction  343  to the disc drive  303  and an output of the disc drive  303  to the buffer for speech reproduction  343  and to the buffer for video reproduction  323 . The system controller  301  is configured for performing control processing based on a vertical synchronization signal from the synchronization separation circuit  310 , a full flag F fu  from the buffer  313  for video recording, an empty flag F em  from buffer  323  for video reproduction and a transfer permission flag  Fok  from the disc drive  303 . 
     There is provided on the output side of the D/A converter  321  a switch  320  to which are supplied video signals from the input terminal I 3a  and video signals from the D/A converter  321 . There is also provided on the output side of the D/A converter  341  a switch  340  to which are supplied speech signals from the input terminal I 3c  and speech signals from the D/A converter  341 . Under switching control by the system controller  301 , not shown, the switches  320 ,  340  are changed over to the input terminal I 3a  and to the input terminal I 3c  during the recording operation, respectively, and to the D/A converters  321 ,  341  during the playback operation, respectively. 
     There is also provided on the input side of the buffer for speech reproduction a switch  344  to which are supplied speech data from the compression circuit  332  and speech data derived from the disc drive  303 . Under switching control by the system controller  301 , not shown, the switch  344  is changed over to the side of the compression circuit  332  and to the side of the disc drive  303  during the recording operation and during the reproducing operation, respectively. 
     The above-described recording/reproducing apparatus uses a one-shoat playback system of temporarily interrupting the recording operation and a parallel recording/reproducing system of performing the payback operation while continuing the recording operation, in order to permit the user to regressively view the scene he or she has just viewed for a moment. 
     Referring to FIG. 2, if video signals and speech signals VA 0 , VA 1 , VA 2 , . . . from a tuner receiving the live broadcast, referred to herein as input signals, are supplied to the recording/reproducing apparatus  300 , and the playback mode by the one-shot playback system, referred to herein as one-shot playback mode, is set directly after the end of inputting of the input signal VA 5  by the key input by the user, the recording/reproducing apparatus  300  momentarily discontinues the recording operation at the same time as the one-shot playback mode is set. At this time, the input signals VA 0  to VA 5  have been recorded on the disc  302 . The recording/reproducing apparatus  300  then reproduces the previously recorded input signals VA 2  to VA 5  from the disc  302 . Subsequently, the recording/reproducing apparatus  300  starts the recording operation for the currently inputted input signals VA 10 , VA 11 , . . . 
     Thus, until the recording/reproducing apparatus  300  is set to the one-shot playback mode, a live picture corresponding to the input signals VA 0  to VA 5  from the tuner, not shown, for receiving the live broadcast, is displayed on the monitor, not shown. Once the recording/reproducing apparatus  300  is set to the one-shot playback mode, the playback picture corresponding to the input signals VA 2  to VA 5  is displayed on the monitor. The recording/reproducing apparatus  300  does not perform the recording operation for the input signals VA 6  to VA 9  entered during the period the playback picture is displayed on the monitor. After the end of display of the playback picture corresponding to the input signals VA 2  to VA 5 , a live picture corresponding to the currently inputted input signals VA 10 , VA 11 , . . . is displayed. 
     On the other hand, if the playback mode by the parallel recording/reproducing system, referred to herein as the parallel recording/reproducing mode, is set for the recording/reproducing apparatus  300  directly after the end of inputting of the input signals VA 5 , by the key input by the user, the recording/reproducing apparatus  300  reproduces the previously recorded input signals VA 2 , VA 3 , VA 4 , . . . from the disc  302 , at the same time as it continues the recording operation. 
     Thus, until the recording/reproducing apparatus  300  is set to the parallel recording/reproducing mode, a live picture corresponding to the input signals VA 0  to VA 5  from the tuner, not shown, designed for receiving the love broadcast, is displayed on a monitor, not shown. Once the recording/reproducing apparatus  300  is set to the parallel recording/reproducing mode, the playback picture corresponding to the input signals VA 2 , VA 3 , VA 4 , . . . is displayed on the monitor. Under this condition, the recording/reproducing apparatus  300  performs the recording operation for the currently entered input signals VA 6 , VA 7 , VA 8 , . . . 
     For performing the above-described one-shot playback mode operation and parallel recording/reproducing mode operation, the recording/reproducing apparatus  300  performs full-field playback operation and frame-skip playback operation during the one-shot playback mode operation and parallel recording/reproducing mode operation, respectively, using a first format comprised of blocks of plural fields constituted by the speech and the video not thinned out on the time axis and a second format comprised of plural blocks constituted by the speech not thinned out on the time axis and video thinned out on the time axis. 
     For example, if the recording/reproducing apparatus  300  manages picture data and speech data for  8  vertical synchronization periods (V), a format  300   a  for one block of the first format includes speech data A 1  for 1 V, a video data V 1  for 1 V, speech data A 2  for 1 V, . . . video data V 2  for 1 V, . . . speech data A 8  for 1 V and video data V 8  for 1 V, recorded in succession to the speech data A for 8 V, as shown in FIG.  4 A. On the other hand, a format  300   b  for one block of the second format includes video data V  1  for 1 V in succession to the speech data A for 8 V. 
     If the recording/reproducing apparatus  300  is not set to the one-shot playback mode, to the parallel recording/reproducing mode nor to the usual playback mode, referred to herein as the usual mode, the recording/reproducing apparatus  300  necessarily records on the disc  302  the video data and the speech data from the tuner, not shown, designed for receiving the live broadcast, in accordance with the format  300   a.    
     FIGS. 5 and 6 are timing charts for input/output data for the buffers  313 ,  323 ,  333  and  343 . In FIGS. 5 and 6, each division of video data V- 6 , V- 5 , V- 4 , . . . and each division of the speech data A- 6 , A- 5 , A- 4 , . . . denotes one-field time of video signals. 
     Referring to FIGS. 1,  4 A,  4 B and  6 , the operation for each set mode of the recording/reproducing apparatus  300  is explained in detail. 
     First, in the usual mode of the recording/reproducing apparatus  300 , the switch  344  is changed over to the side of the compression circuit  332 , under switching control by the system controller  301 . 
     The video signals of V 1 , entering the input terminal I 3a  during the V 1  period, is digitized by the A/D converter  311  and encoded by the compression circuit  312 . 
     Simultaneously, the speech signal A 1  entering the input terminal I 3c  is digitized by the A/D converter  331  and encoded by the compression circuit  332 . 
     The video data V 1 , obtained on encoding by the compression circuit  312 , is stored in the video recording buffer  313 . If video data for 1 V, that is V 1  video data, is stored in the video recording buffer  313 , the full-flag F fu  is set to ‘1’ and routed to the system controller  301 . 
     The A 1  speech data obtained on encoding by the compression circuit  342  is stored in the speech recording buffer  343 . 
     Based on the full flag F fu  (=‘1’) from the video recording buffer  313 , the system controller  301  reads out from the speech recording buffer  333  the speech data A- 6  to A 0  stored therein after encoding by the compression circuit  332 . The system controller  301  routes to the disc drive  303  the command and the address for recording data of the disc  302  and the speech data A- 6  to A 0  read out from the speech recording buffer  333 . 
     Based on the address and the command from the system controller  301 , the disc drive  303  records the speech data A- 6  to A 0  from the system controller  301  on the disc  302 . 
     When the speech data A- 6  to A 0  has been recorded on the disc  302  by the disc drive  303 , the system controller  301  reads out the A 1  speech data stored in the speech recording buffer  343  and routes the read-out speech data to the disc drive  303 . 
     The disc drive  303  records the A 1  speech data from the system controller  301  in an address of the disc  302  next following the A 0  speech data. 
     The system controller  301  then reads out the V 1  video data stored in the video recording buffer  313  and routes the read-out video data to the disc drive  303 . 
     The disc drive  303  records the V 1  video data from the system controller  301  in an address of the disc  302  next following the A 1  speech data. 
     If the V 1  video data is read out by the system controller  301 , the video recording buffer  313  sets the full flag F fu  to ‘0’ which is routed to the system controller  301 . If the 1V video data, that is video data for V 2 , is stored during the next V 2  period, the video recording buffer again sets the full flag F fu  to ‘1’ which is routed to the system controller  301 . 
     Thus the system controller  301  reads out the A 2  speech data stored in the speech recording buffer  343  after encoding by the compression circuit  332  during the V 2  period and routes the read out data to the disc drive  303 . The system controller  301  then reads out the V 2  video data stored in the video recording buffer  313  from the video recording buffer  313  to route the read-out video data to the disc drive  303 . 
     The disc drive  303  then records out the A 2  speech data from the system controller  301  in an address next following the V 1  video data of the disc  302  and subsequently records the V 2  video data in an address next following the A 2  speech data on the disc  302 . 
     By the repetition of the above-described sequence of operations, block data comprised of the A- 6  to A 0  speech data, A 1  video data, V 1  speech data, . . . A 8  speech data and V 8  video data are recorded on the disc  302 , in accordance with the format  300   a , so that plural block data are recorded in succession. 
     If, by the key input by the user, the recording/reproducing apparatus  300  is set to the parallel recording/reproducing mode, the switch  344  is changed over to the side of the disc drive  303  under switching control by the system controller  301 . 
     The system controller  301  routes to the disc drive  303  the command and the address in which is recorded an optional block data selected from the block data continuously recorded on the disc  302  as described above in accordance with the format  300   a.    
     By the address and the command from the system controller  301 , the disc drive  303  reproduces video data and the speech data in the optional block data from the disc  302 . 
     That is, in FIG. 5, the system controller  301  routes to the disc drive  303  the playback command and the address of the disc  302  in which are recorded the A- 6  to A 1  speech data. Thus the disc drive  303  reproduces the A- 6  to A 1  speech data from the disc  302 . 
     The system controller  301  writes the A- 6  to A 1  speech data obtained from the disc drive  303  via switch  344  on the speech reproducing buffer  343  in synchronism with the vertical synchronization signals from the synchronization separation circuit  310 . 
     The disc drive  303  then reproduces V 1  video data from an address next following the A 1  speech data of the disc  302 . 
     After resetting the write address of the video reproducing buffer  323 , the system controller  301  writes the V 1  video data obtained by the disc drive  303  in the video reproducing buffer  323 . 
     The expansion circuit  322  resets the reading of the video reproducing buffer  323  in synchronism with the vertical synchronization signals from the synchronization separation circuit  310  for reading out the V 1  video data stored in the video reproducing buffer  323  eight times on end and for sequentially decoding the read-out video data to route the decoded video data to the switch  320 . 
     At this time, the expansion circuit  342  decodes the A- 6  to A 1  speech data stored in the speech reproducing buffer  343 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  310 , for outputting the decoded speech data via switch  340  and output terminal I 3d  to the speaker. 
     Thus, a playback picture corresponding to the V 1  video signals is displayed for eight fields on the monitor, while the speech corresponding to the speech signals A- 6  to A 1  are outputted via speaker, not shown. 
     If the video data for 8 V and the speech data are reproduced as described above, the recording/reproducing apparatus  300  performs the recording in accordance with the format  300   b.    
     That is, the system controller  301  reads out A 2  to A 9  speech data encoded by the compression circuit  332  and stored in the speech recording buffer  333  during the V 2  to V 9  period. The system controller  301  routes to the disc drive  303  the command and the address next following the V 8  video data of the disc  302  and the A 2  to A 9  speech data read out from the video recording buffer  333 . 
     Based on the address and the command from the system controller  301 , the disc drive  303  records the A 2  to A 9  speech data from the system controller  301  in an address next following the V 8  video data of the disc  302 . 
     The system controller  301  then reads out V 9  video data from the system controller  301  in an address next following the A 9  speech data on the disc  302 . 
     Thus, the A 2  to A 9  speech data and the V 9  video data are recorded on the disc  302  in accordance with the format  300   b.    
     The system controller  301  then routes to the disc drive  303 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  310 , at a timing of the start of the eighth playback of the V 1  video data, an address by which the 8V speech data of from A 2  to A 9  have been recorded on the disc  302 . This enables the disc drive  303  to reproduce the A 2  to A 9  speech data from the disc  302 . 
     The system controller  301  then causes the A 2  to A 9  speech data from the disc drive  303  to be written via switch  344  in the speech reproducing buffer  343 . 
     The disc drive  303  then reproduces the V 9  video data from an address next following the A 9  speech data of the disc  302 . 
     After resetting the write address of the video reproducing buffer  323 , the system controller  301  causes the V 9  video data reproduced from the disc drive  303  to be written in the video reproducing buffer  323 . 
     After read-setting the video reproducing buffer  323  in synchronism with the vertical synchronization signals from the synchronization separation circuit  310 , the expansion circuit  322  reads out the V 9  video data stored in the video reproducing buffer  323  eight times on end and sequentially decodes the read-out data to output the decoded data to a monitor, not shown, via D/A converter  321 , switch  320  and output terminal I 3b . 
     The expansion circuit  342  sequentially decodes, in synchronism with the vertical synchronization signals from the synchronization separation circuit  310 , the A 2  to A 9  speech data stored in the speech reproducing buffer  343 , and outputs the decoded data via D/A converter  341 , switch  340  and output terminal I 3d  to the speaker. 
     This, a playback picture corresponding to the V 9  video signals are displayed for 8 fields on the monitor, while the speech corresponding to the A 2  to A 9  speech signals is outputted by a speaker, not shown. 
     The above playback operation is repeated until ‘stop’ of the parallel recording/reproduction is commanded by the key input by the user. 
     In the recording/reproducing apparatus  300 , block data conforming to the formats  300   a  or  300   b  are continuously recorded on the disc  302  and reproduction is performed beginning from a specified one of the plural block data recorded continuously on the disc  302  which is in accord with the format  300   a . Thus it is supervised by the system controller  303  whether the reproduced block has been recorded in accordance with the format  300   a  or in accordance with the format  300   b.    
     With the above-described conventional recording/reproducing apparatus, such as the above-described conventional recording/reproducing apparatus  300 , the number of fields of video data of the format  300   b  is one, that is the number of frames during the parallel recording/reproducing mode is one for the number of fields in a block of the format  300   a , as shown in FIG.  4 B. Thus, if 8 V video data and speech data are managed, the playback operation is ⅛ frame-skip operation during the parallel recording/reproduction, resulting in an unnatural picture obtained by the recording/reproducing apparatus. 
     If, for overcoming this problem, the number of reproduced frames is simply increased in carrying out the parallel recording/reproduction, it becomes necessary for the recording/reproducing apparatus to access the recording point and the playback point on the disc alternately a number of times equal to the increased number of the playback frames. Thus, much time is consumed in the seek operation for the disc such that the recording and reproduction cannot be completed within a pre-set time. 
     Moreover, with the above-described recording/reproducing apparatus, since the compression and expansion need to be performed on the video signals at all times for the parallel recording/reproducing mode, it is necessary to provide a compression circuit separately from the expansion circuit. Since these circuits are costly, the recording/reproducing apparatus cannot be reduced in production cost. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a recording/reproducing apparatus in which a satisfactory playback picture can be obtained for the parallel recording/reproducing mode. 
     It is another object of the present invention to provide a recording/reproducing apparatus in which production cost can be reduced. 
     The present invention provides a recording/reproducing apparatus in which video signals and speech signals are recorded in synchronism with each other on an overwrite type disc-shaped recording medium based on a selected setting of the processing mode, and in which the video and the speech are reproduced in synchronism with each other from the recording medium having the video signals and the speech signals recorded thereon. The apparatus includes storage means for storing the video signals obtained from the recording medium, decoding means for decoding the video signals stored in the storage means, holding means for holding the video signals decoded by the decoding means and control means for controlling the address management and data transfer for the recording medium and for controlling the overall operation of the apparatus. In the processing mode in which the recording and the reproduction are carried out alternately so that reproduction is performed while the recording is going on, the storage means stores plural fields of the video signals and the holding means performs interpolation of video signals. 
     In the recording/reproducing apparatus according to the present invention, the signal processing means has the expansion function of decoding the video signals stored in the storage means, and the compression function of encoding the video signals recorded on the recording medium. In the processing mode in which the recording and the reproduction are carried out alternately so that reproduction is performed while the recording is going on, the control means switches the operating timing of the entire apparatus and switches between the expansion function and the compression function of the signal processing means so that the recording operation and the reproducing operation will be carried out alternately. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram showing a conventional recording/reproducing apparatus. 
     FIG. 2 illustrates a one-shot reproduction system. 
     FIG. 3 illustrates the parallel recording/reproducing system. 
     FIG. 4 illustrates a disc format employed in the recording/reproducing apparatus shown in FIG.  1 . 
     FIG. 5 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 1 is set to the parallel recording/reproducing mode, with the input video signals being V- 6  to V 21 . 
     FIG. 6 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 1 is set to the parallel recording/reproducing mode, with the input video signals being V 21  ff. 
     FIG. 7 is a block diagram showing the structure of a recording/reproducing apparatus according to the present invention. 
     FIG. 8 is a block diagram showing a system in which a tuner and a monitor are connected to the recording/reproducing apparatus shown in FIG.  7 . 
     FIG. 9 illustrates a disc format employed in the recording/reproducing apparatus shown in FIG.  7 . 
     FIG. 10 is a timing chart in case the recording/reproducing apparatus shown in FIG. 7 is set to the one-shot reproducing mode, 
     FIG. 11 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 7 is set to the parallel recording/reproducing mode, with the input video signals being V- 6  to V 20 . 
     FIG. 12 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 7 is set to the parallel recording/reproducing mode, with the input video signals being V 20  ff. 
     FIG. 13 is a block diagram showing a recording/reproducing apparatus in which a compression circuit and an expansion circuit are unified together. 
     FIG. 14 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 7 is set to the parallel recording/reproducing mode, with the input video signals being V- 8  to V 20 . 
     FIG. 15 shows a timing chart in case the recording/reproducing apparatus shown in FIG. 7 is set to the parallel recording/reproducing mode, with the input video signals being V 20  ff. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings, a preferred embodiment of the present invention will be explained in detail. 
     The recording/reproducing apparatus is a recording/reproducing apparatus  100  shown in FIG.  7 . 
     The recording/reproducing apparatus  100  is configured for recording/reproducing video and speech signals for an overwrite type disc  102 , and uses a one-shot playback system and a parallel recording/reproducing system. 
     To the recording/reproducing apparatus  100  are connected a tuner  150  for receiving the live broadcast and a monitor  160  for outputting the video and the speech corresponding to the video and speech signals obtained by the recording/reproducing apparatus  100 . Specifically, to input terminals I 1a , I 1c  of the recording/reproducing apparatus  100  shown in FIG. 7 is connected a tuner  150 . To output terminals I 1b , I 1d  of the recording/reproducing apparatus  100  shown in FIG. 7 is connected a monitor  160 . To the input terminal  11   a  are entered video signals from the tuner  150 , whereas, to the input terminal I 1c  are supplied speech signals from the tuner  150 . From the output terminal I 1b  are outputted video signals to the monitor  160 , whereas, from the output terminal I 1d  are outputted speech signals to the monitor  160 . 
     The recording/reproducing apparatus  100  is explained in more detail. 
     Referring to FIG. 7, the recording/reproducing apparatus  100  includes an A/D converter  111  fed with video signals via input terminal I 1a , and a synchronization separation circuit  110 . The recording/reproducing apparatus  100  also includes a compression circuit  112  fed with outputs of the A/D converter  111  and the synchronization separation circuit  110 . The recording/reproducing apparatus  100  also includes a FIFO buffer fed with an output of the compression circuit  112  and an A/D converter  131  fed with the speech signals entering the input terminal I 1c . The FIFO buffer  113  is referred to herein as a video recording buffer. The recording/reproducing apparatus  100  also includes a compression circuit  132  fed with outputs of the A/D converter  131  and the synchronization separation circuit  110  and a FIFO buffer  133  fed with output of the compression circuit  132 . The FIFO buffer  133  is referred to herein as a speech recording buffer. The recording/reproducing apparatus  100  further includes a disc drive  103  fed with outputs of the speech recording buffer  113  and with the speech recording buffer  133 . 
     The recording/reproducing apparatus  100  also includes a switch  144  fed with outputs of the compression circuit  132  and the disc drive  103 , and FIFO buffer fed with an output of the switch  144 . The FIFO buffer  143  is referred to herein as a speech reproducing buffer. The recording/reproducing apparatus  100  also includes an expansion circuit  142  fed with outputs of the speech reproducing buffer  143  and the synchronization separation circuit  110  and an D/A converter  141  fed with an output of the expansion circuit  142 . The recording/reproducing apparatus  100  also includes a switch  140  fed with an output of the D/A converter  141  and with the speech signal entering the input terminal I 1c  for outputting to the monitor  160  shown in FIG. 8 and a FIFO buffer  123  fed with an output of the disc drive  103 . The FIFO buffer  123  is referred to herein as a video reproducing buffer. The recording/reproducing apparatus  100  also includes an expansion circuit  122  fed with outputs of the speech reproducing buffer  123  and the synchronization separation circuit  110 . The recording/reproducing apparatus  100  also includes a field memory  124  fed with an output of the expansion circuit  122  and a D/A converter  121  fed with an output of the field memory  124 . The recording/reproducing apparatus  100  further includes a switch  120  fed with an output of the D/A converter  121  and the video signals entering the input terminal I 1a  for outputting via output terminal I 1b  to the monitor  160  shown in FIG.  8 . An output of the speech reproducing buffer  143  is supplied to the disc drive  103 . 
     The recording/reproducing apparatus  100  also includes a system controller  101  for controlling an output of the buffer for video recording  113  fed to the disc drive  103 , an output of the buffer for speech recording  133  fed to the disc drive  103 , an output of the buffer for speech reproduction  143  fed to the disc drive  103  and an output of the disc drive  103  fed to the buffer for speech reproduction  143  and to the buffer for video reproduction  123 . The system controller  101  is configured for performing control processing based on a vertical synchronization signal from the synchronization separation circuit  110 , a full flag F fu  from the buffer  113  for video recording an empty flag F em  from the buffer for and a transfer permission flag F ok  from the disc drive  103 . 
     The switches  120 ,  140  are changed over to the input terminal I 1a  and to the input terminal I 1c , respectively, during recording, while being changed over to the D/A converters  121 ,  141 , respectively, during reproduction, under control by the system controller  101  in a manner not shown. The switch  144  is also changed over to the compression circuit  132  during recording, while being changed over to the disc drive  103  during reproduction, under control by the system controller  101  in a manner not shown. 
     In the recording/reproducing apparatus  100 , the field memory  124  is provided on the output side of the expansion circuit  122 . The field memory is fed with outputs of the expansion circuit  122  and the synchronization separation circuit  110  for outputting to the D/A converter  121 . Thus the output of the expansion circuit  122  is routed via field memory  124  to the D/A converter  121 . 
     Data input/output in the field memory  124  is controlled by the system controller  101  in a manner not shown. 
     The above-described recording/reproducing apparatus  100  is configured for recording video data and speech data on the disc  102  in accordance with a first format comprised of blocks of plural fields constituted by the speech and the video not thinned out on the timing axis and a second format comprised of plural blocks constituted by the speech not thinned out on the time axis and video thinned out on the time axis. 
     The recording/reproducing apparatus  100  is configured for managing video data and speech data for 8 V. Referring to FIG. 9A, a format  100   a  for one block of the first format includes speech data A 1  for 1 V, a video data V 1  for 1 V, speech data A 2  for 1 V, a video data V 2  for 1 V . . . speech data A 8  for 1 V and video data V 8  for 1 V, recorded in succession to the speech data A for 8 V, as shown in FIG.  9 A. On the other hand, a format  300   b  for one block of the second format includes video data V 1  and V 5  for 2 V, selected from 8 V, in succession to the speech data A for 8 V. 
     If the recording/reproducing apparatus  100  is not set to the one-shot playback mode, to the parallel recording/reproducing mode nor to the usual mode, the recording/reproducing apparatus  100  performs the recording operation in accordance with the format  100   a.    
     Referring to FIGS. 7 and 8, a series of operations of the recording/reproducing apparatus  100  during the usual mode is explained. 
     The A/D converter  111  digitizes the video signals entering the input terminal I 1a  and routes the digitized video signals as video data to the compression circuit  112 . 
     The A/D converter  131  also digitizes the speech signals entering the input terminal I 1c  and routes the digitized speech signals as speech data to the compression circuit  132 . 
     At this time, the synchronization separation circuit  110  extracts the vertical synchronization signals from the video signals entering the input terminal I 1a  and routes the extracted vertical synchronization signals to the compression circuit  112 , expansion circuit  122 , compression circuit  132 , expansion circuit  142  and to the system-controller  101 . 
     The compression circuit  112  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  to encode the video data from the A/D converter  111  to write the encoded video data in the video recording buffer  113 . 
     The compression circuit  132  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  to encode the speech data from the A/D converter  131  to write the encoded speech data in the speech recording buffer  133  and to route the encoded speech data to the switch  144 . 
     Since the switch  144  is changed over to the compression circuit  132  under switching control of the system controller  101 , in a manner not shown. Thus, the speech data encoded by the compression circuit  132  is also written via switch  144  in the speech reproducing buffer  143 . 
     If video data for 1 V is stored in the video recording buffer  113 , the video recording buffer sets the full flag F fu  to ‘1’ which is outputted to the system controller  101 . 
     If the system controller  101  has recognized, by the full flag F fu (=‘1’), that 1 V of video data has been stored in the video recording buffer  113 , the system controller  101  issues a command and an address for data recording on the disc  102  to the disc drive  103 . The system controller  101  is then in a stand-by state for receiving a transmission permission flag F ok  from the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  outputs the transmission permission flag F ok  to the system controller  101 . 
     If the system controller  101  has recognized that the transmission permission flag F ok  has been outputted by the disc drive  103 , the system controller reads out speech data stored in the speech recording buffer  133  and the speech reproducing buffer  143  for routing the read-out speech data to the disc drive. 
     The system controller  101  also reads out the video data stored in the video recording buffer  113  to transmit the read-out data to the disc drive  103 . 
     When the stored video data has been read out by the system controller  101 , the video recording buffer  113  sets the full flag F fu  to ‘0’. 
     Based on the address and the command from the system controller  101 , the disc drive  103  records the speech data and the video data from the system controller  101  on the disc  102  in accordance with the format  100   a.    
     By the repetition of the above-described sequence of operations, video data and speech data conforming to the live broadcast received by the tuner  150  is recorded on the disc  102  in accordance with the format  100   a.    
     The recording operation in accordance with the format  100   a  of the recording/reproducing apparatus  100  will be explained in detail subsequently. 
     For reproducing the video data and the speech data recorded on the disc  102  as described above, the system controller  101  issues to the disc drive  103  a command and an address where the data of the disc  102  to be reproduced is recorded, and is then in stand-by state to await the transmission permission flag F ok  from the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  outputs the transmission permission flag F ok  to the system controller  101  and subsequently reproduces the speech data and the video data from the disc  102 . 
     If the system controller  101  has recognized that the transmission permission flag F ok  has been sent from the disc drive  103 , the system controller  101  sends speech data reproduced from the disc drive  103  to the switch  144 , while writing the video data reproduced by the disc drive  103  in the video reproducing buffer  123 . 
     Since the switch  144  is changed over at this time to the side of the system controller  103  under switching control by the system controller  101 , in a manner not shown, the speech data sent from the system controller  101  to the switch  144  is written in the speech reproducing buffer  143 . 
     Until storage of the video data for 1 V, the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the empty flag so set to the system controller  101 , for placing the data transfer request for the system controller  101 . 
     On storage of the video data for 1 V, the video reproducing buffer  123  sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Simultaneously, the expansion circuit  122  is synchronized with the vertical synchronization signal from the synchronization separation circuit  110  to read out video data stored in the video reproducing buffer  123  for decoding. 
     The expansion circuit  142  is also synchronized with the vertical synchronization signal from the synchronization separation circuit  110  to read out video data stored in the speech reproducing buffer  143  for decoding. 
     The expansion circuit  122  routes the decoded video data via field memory  124  to the D/A converter  121 . 
     The field memory  124  is designed to effect through-pass of video data from the expansion circuit  122  under control by the system controller  101 , in a manner not shown. 
     The expansion circuit  142  sends the decoded speech data to the D/A converter  141 . 
     The D/A converter  121  converts the video data supplied from the expansion circuit  122  through the field memory  124  into analog data which is supplied as video signals to the switch  120 . 
     Since the switch  120  is changed over at this time to the side of the D/A converter  121  under switching control by the system controller  101 , the video signals sent to the switch  120  from the D/A converter  121  are supplied via output terminal I 1b  to the monitor  160 . 
     The D/A converter  141  converts the speech data from the expansion circuit  142  into analog data which is supplied to the switch  140 . Thus the speech signals supplied from the D/A converter  141  to the switch  140  are supplied via output terminal I 1d  to the monitor  160 . 
     When the video data stored in the video reproducing buffer  123  is read out by the expansion circuit  122  and fed to the monitor  160 , the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ which is outputted to the system controller  101  to request the system controller  101  to transfer data again. 
     This causes the system controller  101  to issue to the disc drive  103  a command and an address where the data to be reproduced next is recorded. 
     By repetition of the above-described playback operation, the video data and the speech data recorded on the disc  102  are reproduced. The monitor  160  displays the playback picture corresponding to the video data recorded on the disc  102 , while a speaker, not shown, outputs the speech corresponding to the speech data recorded on the disc  102 , that is the speech associated with the reproduced picture. 
     It is assumed that, by the key input by the user, the recording/reproducing apparatus  100  is set to the one-shot playback mode or the parallel recording/reproducing mode during the usual mode. 
     FIG. 10 is a time chart of input/output data for the buffers  113 ,  123 ,  133 ,  143  when the recording/reproducing apparatus  100  is set to the one-shot playback mode, while FIGS. 11 and 12 are timing charts for the buffers  113 ,  123 ,  133 ,  143  when the recording/reproducing apparatus  100  is set to the parallel recording/reproducing mode during the usual mode. 
     In FIGS. 10 to  12 , each division of video data V- 6 , V- 5 , V- 4 , . . . and speech data A- 6 , A- 5 , A- 4 , . . . denotes on field time of video signals. 
     If the recording/reproducing apparatus  100  is in the usual mode, video data and the speech data are recorded on the disc  102  in accordance with the format  100   a , as described above. 
     Specifically, the video signals inputted during the V 1  time is encoded during the same one V 1  period by the compression circuit  112  so as to be written in the video recording buffer  113 , as shown in FIG.  10 . 
     When the 1V video data, that is video data V 1 , is stored in the video recording buffer  113 , the video recording buffer  113  sets the full flag F fu  to ‘1’ which is outputted to the system controller  101 . 
     By the full flag F fu  (=‘1’) from the vide recording buffer  113 , the system controller  101  routes the command and the address for recording data on the disc  102  to the disc drive  103 . The system controller  101  reads out A- 6  to A 0  speech data encoded in the compression circuit  132  during the V- 6  to V 0  period and stored in the speech recording buffer  133  from the speech recording buffer  133  to supply the read-out speech data to the drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  records A- 6  to A 0  speech data from the system controller  101  on the disc  102  in accordance with the format  100   a.    
     The system controller  101  then reads out from the speech reproducing buffer  143  encoded by the compression circuit  132  during the V 1  period and stored in the buffer  143 , and routes the read-out speech data to the disc drive  103 . 
     The disc drive  103  records the A 1  speech data from the system controller  101  in an address next following the A 0  speech data of the disc  102  in accordance with the format  100   a.    
     The system controller  101  reads out the V 1  video data stored in the video recording buffer  113  from the video recording buffer  113  to route the read-out video data to the disc drive  103 . 
     The disc drive  103  records the V 1  video data from the system controller  101  in an address next following the A 1  speech data of the disc  102  in accordance with the format  100   a.    
     When the video data for 1 V , that is the V 1  video data, is read out by the system controller  101 , the video recording buffer  113  sets the full flag F fu  to ‘0’ which is outputted to the system controller  101 . 
     By the full flag F fu  (=‘1’) from the video recording buffer  113 , the system controller  101  reads out the A 2  speech data encoded by the compression circuit  132  during the V 2  period and stored in the speech reproducing buffer  143  from the speech reproducing buffer  143  to route the read-out data to the disc drive  103 . 
     The disc drive  103  records the A 2  speech data from the system controller  101  in an address next following the V 1  video data of the disc  102  in accordance with the format  100   a.    
     The system controller  101  reads out the V 2  video data stored in the video recording buffer  113  from the video recording buffer  113  to route the read-out video data to the disc drive  103 . 
     The disc drive  103  records the V 2  video data from the system controller  101  in an address next following the A 2  speech data of the disc  102  in accordance with the format  100   a.    
     By the repetition of the above-described recording operation, block data made up of the A- 6  to A 0  speech data, speech data A 1  for 1 V, video data V 1  for 1 V, speech data A 2  for 1 V, video data V 2  for 1 V, . . . , speech data A 8  for 1 V and video data V 8  for 1 V, is recorded on the disc  102  in accordance with the format  100   a , so that plural block data are recorded continuously. If, by the key input by the user, the recording/reproducing apparatus is set to the one-shot playback mode, the system controller  101  performs control for changing over the switches  120 ,  140  to the sides of the D/A converters  121  and  141 , respectively, in a manner not shown, and for changing over the switch  144  to the side of the disc drive  103 . 
     The system controller  101  selects a specified one of plural block data continuously recorded on the disc  102  in accordance with the format  100   a  and routes to the disc drive  103  the command and the address where there is recorded the A 1  speech data to be reproduced first in the selected block data made up of A- 6  to A 0  speech data, speech data A 1  for 1 V, video data V 1  for 1 V, speech data A 2  for 1 V, video data V 2  for 1 V, speech data A 8  for 1 V and video data V 8  for 1 V. 
     The disc drive  103  reproduces A 1  speech data from the disc  102  by the address and the command from the system controller  101 . 
     The system controller  101  writes the A 1  speech data obtained form the disc drive  103  via switch  144  in the speech reproducing buffer  143 . 
     The disc drive  103  reproduces V 1  video data next following A 1  speech data on the disc  102 . 
     The system controller  101  writes the V 1  video data reproduced by the disc drive  103  in the video reproducing buffer  123 . 
     Until video data for 1 V, that is V 1  video Data, is stored in the video reproducing buffer  123 , the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the flag to the system controller  101  in order to request the system controller  101  to transfer data. 
     On storage of the video data for V 1 , the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the flag thus set to the system controller  101  to terminate the request for data transfer to the system controller  101  transiently. 
     Simultaneously, the expansion circuit  122  is synchronized with the vertical synchronization signal from the synchronization signal separating circuit  110  to read out and decode the V 1  video data stored in the video reproducing buffer  123 . The V 1  video data decoded by the expansion circuit  122  is passed through the field memory  124 , under control by the system controller  101 , in a manner not shown, so as to be outputted via D/A converter  121 , switch  120  and output terminal I 1b  to the monitor  160 . 
     The expansion circuit  142  is synchronized with the vertical synchronization signal from the synchronization signal separating circuit  110  to read out and decode the A 1  speech data stored in the speech reproducing buffer. The A 1  speech data decoded by the expansion circuit  142  is outputted to the monitor  160  via D/A converter  141 , switch  140  and output terminal I 1d . 
     When the stored V 1  video data is read out by the expansion circuit  122  so as to be outputted to the monitor  160 , the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ to output the flag so set to the system controller  101  to start a data transfer request for the system controller  101 . 
     The system controller  101  routes to the disc drive  103  the command and the address where the A 2  speech data to be reproduced next from the system controller  101  to the disc drive  103 . 
     The disc drive  103  reproduces the A 2  speech data from the disc  102  by the address and the command from the system controller  101 . 
     The system controller  101  writes the A 2  speech data obtained from the disc drive  103  via switch  144  in the speech reproducing buffer  143 . 
     The disc drive  103  then reproduces the V 2  video data from the address next following the A 2  speech data of the disc  102 . 
     On storage of the V 2  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ and outputs the flag so set to the system controller  101  to terminate the data transfer request to the system controller transiently. 
     Simultaneously, the expansion circuit  122  is synchronized with the vertical synchronization signals from the synchronization separation circuit  110  to read out and decode V 2  video data stored in the video reproducing buffer  123 . The V 2  video data decoded by the expansion circuit  142  is adapted to pass through the field memory  124  under control by the system controller  101 , in a manner not shown so as to be outputted via D/A converter  121 , switch  120  and output terminal I 1b  so as to be outputted to the monitor  160 . 
     The expansion circuit  142  is synchronized with the vertical synchronization signals from the synchronization separation circuit  110  to read out and decode A 2  speech data stored in the speech reproducing buffer. The A 2  speech data decoded by the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  so as to be outputted to the monitor  160 . 
     Thus, if the playback mode set is the one-shot playback mode, the above-described playback operation is repeatedly performed for reproducing the A 1  to A 8  speech data and V 1  to V 8  video data recorded on the disc  102 . The monitor  160  displays a playback picture corresponding to the V 1  to V 8  video data, while the speaker, not shown, outputs the speech corresponding to the A 1  to A 8  speech data, that is the speech corresponding to the reproduced picture. 
     On the other hand, if the recording/reproducing apparatus  100 b is set to the parallel recording/reproducing mode, by, for example, the key entry by the user, the system controller  101  performs controls for changing over the switches  120  and  140  to the sides of the D/A converter  121  and the D/A converter  141 , respectively, while also performing control for changing over the switch  144  to the side of the disc drive  103 , in a manner not shown. 
     Referring to FIG. 11, the system controller  101  selects a specified one of plural block data recorded continuously on the disc  102  in accordance with the format  100   a  and routes to the disc drive  103  the command and the address of the selected block data, made up of the A- 6  to A 0  speech data, speech data A 1 , video data V 1 , speech data A 2 , video data V 2 , . . . , speech data A 8  and video data V 8 , where the speech data A- 6  to A 0  to be reproduced first is recorded. 
     The disc drive  103  reproduces the speech data A- 6  to A 0  by the address and the command from the system controller  101 . 
     The system controller  101  writes the speech data A- 6  to A 0  obtained by the disc drive  103  in the speech reproducing buffer  143  via switch  144 . 
     The system controller  101  then routes to the disc drive  103  the command and the address where the V 1  video data are recorded. 
     The disc drive  103  reproduces the V 1  video data from an address next following the A 1  speech data of the disc  102  by the address and the command from the system controller  101 . 
     The system controller  101  writes the V 1  video data obtained from the disc drive  103  in the video reproducing buffer  123 . 
     Until storage of the video data for 1 V, that is the V 1  video data, the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the empty flag so set to the system controller  101 , for placing the data transfer request with the system controller  101 . 
     On storage of the V 1  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Simultaneously, the expansion circuit  122  reads out and decodes the video data V 1  stored in the video reproducing buffer  123 . 
     In the case of the parallel recording/reproducing mode, the V 1  video data decoded by the expansion circuit  122  is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown, and is adapted to pass through the field memory  124  so as to be outputted via D/A converter  121 , switch  120  and output terminal I 1b  so as to be outputted to the monitor  160 . 
     The expansion circuit  142  is synchronized with the vertical synchronization signals from the synchronization separation circuit  110  to read out and decode A- 6  speech data stored in the speech reproducing buffer  143 . The A- 6  speech data decoded by the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  so as to be outputted to the monitor  160 . 
     If the V 1  video data is read out by the expansion circuit  122  and outputted to the monitor  160 , the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ to output the flag so set to the system controller  101  to start the data transfer request to the system controller  101 . 
     Thus the system controller  101  routes the command and the address where the V 5  vide data is recorded to the disc drive  103 . 
     The disc drive  103  reproduces the V 5  video data from the disc  102  by the address and the command from the system controller  101 . 
     The system controller  101  writes the V 5  video data obtained from the disc drive  103  in the video reproducing buffer  123 . 
     On storage of the V 5  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101  . 
     If, in the parallel recording/reproducing mode, the V 1  video data is written in the field memory  124 , data readout in the video reproducing buffer  123  or the data writing in the field memory  124  is not performed until end of outputting of A- 6  to A- 3  speech data for 4 V comes to a close, that is for four fields. 
     That is, during the next 1 V, the V 1  video data written in the field memory  124  is outputted, in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , via the D/A converter  121 , switch  120  and output terminal I 1b  to the monitor  160 , under control by the system controller  101 , in a manner not shown. 
     Simultaneously, the expansion circuit  142  reads out and decodes the A- 5  speech data stored in the speech reproducing buffer synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 5  speech data, decoded by the expansion circuit  142 , is outputted via D/A converter  141 , switch  140  and output terminal I 1d  to the monitor  160 . 
     During the next 1V period, the V 1  video data, written in the field memory  124 , is outputted, in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160  under control by the system controller  101 , in a manner not shown. 
     Simultaneously, the expansion circuit  142  reads out and decodes the A- 4  speech data stored in the speech reproducing buffer in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 4  speech data, decoded by the expansion circuit  142 , is outputted via D/A converter  141 , switch  140  and output terminal I 1d  to the monitor  160 . 
     During the next 1V period, the V 1  video data, written in the field memory  124 , is outputted, in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , via D/A converter  121 , switch  120  and output terminal I 1b  to the monitor  160  under control by the system controller  101 , in a manner not shown. 
     Simultaneously, the expansion circuit  142  reads out and decodes the A- 3  speech data stored in the speech reproducing buffer in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 3  speech data, decoded by the expansion circuit  142 , is outputted via D/A converter  141 , switch  140  and output terminal I 1d  sequentially to the monitor  160 . 
     During the next 1V period, the expansion circuit  122  reads out V 5  video data stored in the video reproducing buffer for decoding. 
     The V 5  video data, decoded by the expansion circuit  122 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 5  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . The 
     The expansion circuit  142  reads out and decodes A- 2  speech data stored in the speech reproducing buffer in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 2  speech data recorded in the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  sequentially to the monitor  160 . 
     If the V 5  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until outputting of the A 2  to A 1  speech data to the monitor  160  comes to a close, that is for a four-field period. 
     During the three-field period as from the next 1 V, three fields of the V 5  video data is outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , at the same time as A- 1 , A 0  and A 1  speech data are outputted to the monitor  160 . 
     This reproduces V 1  video data, V 5  video data and A- 6  to A 1  speech data. 
     It V 5  video data has been stored in the video reproducing buffer  123 , the recording/reproducing apparatus performs a recording operation conforming to the format  100   b . If the playback mode is the parallel reproducing mode, the video compressing operation is executed every four fields. In FIG. 11, V 9  video data, V 13  video data, V 17  video data and V 21  video data and so forth are compressed and stored in the video recording buffer  113 . 
     The system controller  101  routes a command and an address to be recorded data of the disc  102  to the disc drive  103  and then enters into the state of awaiting the transfer permission flag F ok  from the disc drive  103 . 
     On recognition of the outputting of the transfer permission flag F ok  from the disc drive  103 , the system controller  101  reads out speech data A 2  to A 9  for 8 V stored in the speech recording buffer  133  to route the read-out speech data to the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  records the speech data A 2  to A 9  for 8 V from the system controller  101  in an address next following the A 9  speech data of the disc drive  102  in accordance with the format  100   b.    
     The system controller  101  also sequentially reads out V 9  video data and V 13  video data stored in the video recording buffer  113  to route the read-out data to the disc drive  103 . 
     Thus, the speech data A 2  to A 9 , V 9  video data and V 13  video data are recorded on the disc  102  in continuation to the block data recorded in accordance with the format  100   b.    
     The recording/reproducing apparatus  100  reproduces the speech data A 2  to A 9  for 8 V and V 9 , V 13  video data for 2 V recorded in accordance with the format  100   b  as described above. 
     As in the reproducing operation for the V 1  and v 5  video data and the speech data A 9  to A 1 , described above, the system controller  101  routes to the disc drive  103  the command and the address where the A 2  to A 9  speech data for 8 V are recorded. 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces the speech data A 2  to A 9  for 8 V from the disc  102 . 
     The system controller  101  writes the speech data A 2  to A 9  for 8 V reproduced by the disc drive  103  in the speech reproducing buffer  143  via switch  144 . 
     The system controller  101  then routes to the disc drive  103  the command and the address where the V 9  video data has been recorded. 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces V 9  video data from the address next following the A 9  speech data of the disc  102 . 
     The system controller  101  writes the V 9  video data reproduced by the disc drive  103  in the video reproducing buffer  123 . 
     Until storage of the V 9  video data, the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the empty flag so set to the system controller  101 , for placing the data transfer request with the system controller  101 . 
     On storage of the V 9  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Simultaneously, the expansion circuit  122  reads out and decodes the V 9  video data stored in the video reproducing buffer  123 . 
     The V 9  video data decoded by the expansion circuit  122  is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110  under control by the system controller  101 , in a manner not shown. The V 9  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A- 2  speech data stored in the speech reproducing buffer in synchronization with the vertical synchronization signals from the synchronization separation circuit  110 . The A 2  speech data decoded by the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  to the monitor  160 . 
     If the V 9  video data is read by the expansion circuit  122  and outputted to the monitor  160  shown in FIG. 8, the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ and outputs the flag so set to the system controller  101  to start data transfer request to the system controller  101 . 
     The system controller  101  thus routes to the disc drive  103  the command and the address where is recorded the V 13  video data. 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces V 13  video data from the address next following the V 9  video data of the disc  102 . 
     The system controller  101  writes the V 13  video data reproduced by the disc drive  103  in the video reproducing buffer  123 . 
     On storage of the V 13  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Once the V 9  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until the outputting of the A 2  to A 5  speech data to the monitor  160  comes to a close, that is for a four-field period. 
     Thus, during the three-field period, beginning from the next 1V, three fields of the V 9  video data are outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , while A 3  to A 5  speech data are outputted to the monitor  160 . 
     During the next 1V period, the the expansion circuit  122  reads out V 13  video data stored in the video reproducing buffer for decoding. 
     The V 13  video data, decoded by the expansion circuit  122 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 13  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A 6  speech data stored in the speech reproducing buffer in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A 6  speech data recorded in the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  sequentially to the monitor  160 . 
     If the V 13  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until outputting of the A 6  to A 9  speech data to the monitor  160  comes to a close, that is for a four-field period. 
     During the three-field period as from the next 1V, three fields of the V 13  video data is outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , at the same time as A 7 , A 8  and A 9  speech data are outputted to the monitor  160 . 
     This reproduces the V 9  and V 13  video data and the A 2  to A 9  speech data recorded on the disc  102  in accordance with the format  100   b.    
     If the V 9  video data are stored in the video reproducing buffer  123 , the recording operation for V 17  video data, V 21  video data and A 10  to A 17  speech data similar to the above-described recording operation for V 9  video data, V 13  video data and A 2  to A 9  speech data is carried out in the recording/reproducing apparatus  100  in accordance with the format  100   b.    
     The above-described recording and reproducing operations are then carried out by the recording/reproducing apparatus  100  until ‘stop’ of the parallel recording/reproducing mode is commanded such as by key input by the user. 
     As described above, the recording/reproducing apparatus  100  uses, as a second format comprised of plural blocks constituted by the speech not thinned out on the time axis and video thinned out on the time axis, such a format  100   b  comprised of speech data for 8 V followed by two fields of the video data, and includes the field memory  124  for freezing the video data decoded by the expansion circuit  122  on the output side of the expansion circuit  124 , so that the number of reproduced frames can be easily increased without increasing the number of accessing to the disc  102  during the parallel recording/reproducing mode. Thus the recording/reproducing apparatus  100  can produce a satisfactory playback picture even if the playback mode is the parallel recording/reproducing mode. 
     In recording/reproducing apparatus  100 , since the block data conforming to the format  100   a  or  100   b  are continuously recorded on the disc  102 , and the reproducing operations begins from a specified one of the plural block data continuously recorded on the disc, which is in accord with the format  100   a , it is managed by the system controller  101  in accordance with which of the format  100   a  or the format  100   b  has been recorded the reproduced block format. 
     The recording/reproducing apparatus according to the present invention is applied to a recording/reproducing apparatus  200  shown in FIG.  13 . 
     The recording/reproducing apparatus  200  is configured so that the compression circuit  112  and the expansion circuit  122  of the recording/reproducing apparatus  100  shown in FIG. 7 are unified together. Thus the recording/reproducing apparatus  200  includes a compression/expansion (companding) circuit  201  having both the functions of the compression circuit  112  and the expansion circuit  122 , a switch  202  provided on the input or output side of the companding circuit  201  and a switch  203  provided on the output or input side of the companding circuit  201 . 
     The switch  202  is configured for switching between an output to the companding circuit  201  of the A/D converter  111  and an output to the field memory  124  of the companding circuit  201  under control by the system controller  101 . 
     The switch  203  is configured for switching between an output to the video recording buffer  113  of the companding circuit  201  and an output to the companding circuit  201  of the video reproducing buffer  123  under control by the system controller  101 . 
     Switching between the processing function for the compression circuit  112  (compression mode) and the function for the expansion circuit  122  (expansion mode) owned by the companding circuit  201  is also controlled by the system controller  101 . 
     That is, the system controller  101  controls the switches  202 ,  203  for switching to the A/D converter  111  and to the video recording buffer  113 , respectively, during recording, by way of controlling the companding circuit  201  to operate under the compression mode. The system controller  101  also controls the switches  202 ,  203  for switching to the field memory  124  and to the video reproducing buffer  123 , respectively, during reproduction, by way of controlling the companding circuit  201  to operate under the expansion mode. 
     FIGS. 14,  15  are timing charts for input/output data for the buffers  113 ,  123 ,  133  and  143  for the case in which the recording/reproducing apparatus  200  is set to the parallel recording/reproducing mode. 
     In FIGS. 14 and 15, each division of the video data V- 6 , V- 5 , V- 4 , . . . and speech data A- 6 , A- 5 , A- 4 , denotes one field time duration of video signals. 
     Referring to FIGS. 14 and 15, the operation of the recording/reproducing apparatus  200  when set to the parallel recording/reproducing mode is explained. 
     In the recording/reproducing apparatus  200 , the parts or components operating similarly to those of the recording/reproducing apparatus  100  shown in FIG. 7 are denoted by the same numerals and are not explained. The operation of the recording/reproducing apparatus  200  during the normal operation and the one-shot playback mode is similar to that of the recording/reproducing apparatus  100  during the normal operation and the one-shot playback mode, so that the detailed description is omitted for simplicity. 
     First, if the recording/reproducing apparatus  200  is in the usual mode, the video data and the speech data are recorded on the disc  102  in accordance with the format  100   a , as explained previously. 
     If the recording/reproducing apparatus  200  is set to the parallel recording/reproducing mode by the key input by the user, the recording/reproducing apparatus  200  records video data and speech data in accordance with the format  100   b , in contrast to the recording/reproducing apparatus  100  selecting a specified one of plural block data continuously recorded on the disc  102  in accordance with the format  100   a , and reproducing video data and speech data of the selected block data. 
     That is, at an input timing of video signals during the V 9  period, the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 9  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     Also, at an input timing of video signals during the V 13  period, the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 13  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     If the video data V 9  and V 13  have been stored in the video recording buffer  113 , the system controller  101  routes the command and the address of recording data on the disc  102  to the disc drive  103  and is set to the state of awaiting the transfer permission flag F ok  from the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  outputs the transfer permission flag F ok  to the controller  101 . 
     On recognition of the outputting of the transfer permission flag F ok  from the disc drive  103 , the system controller  101  reads out speech data A 2  to A 9  for 8 V encoded by the compression circuit  132  during the periods from V 2  to V 9  and stored in the speech recording buffer  133  to route the read-out speech data to the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  records the speech data A 2  to A 9  for 8 V from the system controller  101 . 
     The system controller  101  also sequentially reads out V 9  video data and V 13  video data stored in the video recording buffer  113  to route the read-out data to the disc drive  103 . 
     The disc drive  103  records the V 9  and V 13  video data from the system controller  101  in an address next following the A 9  speech data of the disc  102  in accordance with the format  100   b.    
     Also, at an input timing of video signals during the V 17  period, the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 17  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     When the operation of recording speech data A 2  to A 9  for  8  V and V 9 , V 13  video data for 2 V, in accordance with the format  100   b , comes to a close, the recording/reproducing apparatus  200  proceeds to a reproducing operation. 
     First, the switch  144  is changed over to the side of the disc drive  103 , under control by the system controller  101 , in a manner not shown. 
     The system controller  101  routes to the disc drive  103  the command and the address where the speech data A- 6  to A 1  are recorded on the disc  102 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces the speech data A- 6  to A 1  from the disc  102 . 
     The system controller  101  writes the speech data A- 6  to A 1  obtained by the disc drive  103  in the speech reproducing buffer  143  via switch  144 . 
     The system controller  101  then routes the command and the address where the V 1  video data has been recorded on the disc  101  to the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces the V 1  video data from the disc  102 . 
     The system controller  101  writes the V 1  video data obtained form the disc drive  103  in the video reproducing buffer  123 . 
     Until storage of the V 1  video data, the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the empty flag so set to the system controller  101 , for placing the data transfer request with the system controller  101 . 
     On storage of the V 1  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     At this time, the system controller  101  controls the switches  202  and  203  to be set to the side of the field memory  124  and to the side of the video reproducing buffer  123 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  reads out and decodes the V 1  video data stored in the video reproducing buffer  123  in synchronism with the vertical synchronization signals from the synchronization separating circuit  110 . 
     The V 1  video data, decoded by the companding circuit  201 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 1  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A- 6  speech data stored in the speech reproducing buffer  143  in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 6  speech data decoded by the expansion circuit  142  is outputted via D/A converter  141  and output terminal I 1d  sequentially to the monitor  160 . 
     If the V 1  video data is read by the companding circuit  201  and outputted to the monitor  160 , the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ and outputs the flag so set to the system controller  101  to start data transfer request to the system controller  101 . 
     The system controller  101  thus routes to the disc drive  103  the command and the address where the V 5  video data is recorded on the disc  102 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces V 5  video data from the disc  102 . 
     The system controller  101  writes the V 5  video data obtained by the disc drive  103  in the video reproducing buffer  123 . 
     On storage of the V 5  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Once the V 1  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until the outputting of the speech A- 6  to A- 3  data to the monitor  160  comes to a close, that is for a four-field period, as in the case of the parallel recording/reproducing mode for the recording/reproducing apparatus  100 . Thus, during the three-field period, beginning from the next 1V, three fields of the V 1  video data are outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , while speech data A- 5 , A- 4  and A- 3  are outputted to the monitor  160 . 
     Also, at an input timing of video signals during the V 21  period, during the four fields of the V 1  video data outputted to the monitor  160 , the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 21  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     When the V 1  video data have been outputted to the monitor  160  during the four-field period, the system controller  101  controls the switches  202  and  203  to be set to the side of the field memory  124  and to the side of the video reproducing buffer  123 , respectively, and controls the companding circuit  201  to operate in the expansion mode. 
     The V 5  video data, decoded by the companding circuit  201 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 5  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A 6  speech data stored in the speech reproducing buffer  143  in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A- 2  speech data recorded in the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  to the monitor  160 . 
     If the V 5  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until outputting of the speech data A- 2  to A 1  to the monitor  160  comes to a close, that is for a four-field period, as in the operation during the parallel recording/reproducing mode in the recording/reproducing apparatus  100 . 
     During the three-field period as from the next 1V, three fields of the V 5  video data is outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , at the same time as speech data A- 1 , A 0  and A 1  are outputted to the monitor  160 . 
     Also, at an input timing of the V 5  video signals during the V 25  period, during the outputting of the four fields of the V 5  video data to the monitor  160 , the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 25  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     When the reproducing operation for the A- 6  to A 1  speech data, V 1  vide data and the V 5  video data comes to a close, as described above, the recording/reproducing apparatus  200  proceeds to the recording operation. 
     The system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The system controller  101  routes a command and an address in which to record data of the disc  102  to the disc drive  103  and then enters into the state of awaiting the transfer permission flag F ok  from the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  outputs the transfer permission flag F ok  to the system controller  101 . 
     On recognition of the outputting of the transfer permission flag F ok  from the disc drive  103 , the system controller  101  reads out speech data A 10  to A 17  encoded by the compression circuit  132  during the period V 10  to V 17  and stored in the speech recording buffer  133  to route the read-out speech data to the disc drive  103 . 
     By the address and the command from the system controller  101 , the disc drive  103  records the speech data A 10  to A 17  for 8 V from the system controller  101  in an address next following the V 13  video data of the disc drive  102  in accordance with the format  100   b.    
     The system controller  101  also sequentially reads out V 17  video data and V 21  video data stored in the video recording buffer  113  to route the read-out data to the disc drive  103 . 
     When the operation of recording speech data A 10  to A 17  and V 17 , V 21  video data in accordance with the format  100   b  comes to a close, the recording/reproducing apparatus  200  proceeds to a reproducing operation. 
     The system controller  101  routes to the disc drive  103  the command and the address where the speech data A 2  to A 9  are recorded on the disc  102 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces the speech data A 2  to A 9  from the disc  102 . 
     The system controller  101  writes the speech data A 2  to A 9  obtained by the disc drive  103  in the speech reproducing buffer  143  via switch  144 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces the V 9  video data from an address next following the A 9  speech data of the disc  102 . 
     The system controller  101  writes the V 9  video data obtained from the disc drive  103  in the video reproducing buffer  123 . 
     Until storage of the V 9  video data, the video reproducing buffer  123  sets the empty flag F em  to ‘1’ to output the empty flag so set to the system controller  101 , for placing the data transfer request with the system controller  101 . 
     On storage of the V 9  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     At this time, the system controller  101  controls the switches  202  and  203  to be set to the side of the field memory  124  and to the side of the video reproducing buffer  123 , respectively, and controls the companding circuit  201  to operate in the expansion mode. 
     The companding circuit  201  reads out and decodes the V 9  video data stored in the video reproducing buffer  123  in synchronism with the vertical synchronization signals from the synchronization separating circuit  110 . 
     The V 9  video data, decoded by the expansion circuit  122 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 9  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A 2  speech data stored in the speech reproducing buffer  143  in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A 2  speech data decoded by the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  sequentially to the monitor  160 . 
     If the V 9  video data is read by the companding circuit  201  and outputted to the monitor  160 , the video reproducing buffer  123  again sets the empty flag F em  to ‘1’ and outputs the flag so set to the system controller  101  to start data transfer request to the system controller  101 . 
     The system controller  101  thus routes to the disc drive  103  the command and the address where the V 5  video data is recorded on the disc  102 . 
     By the address and the command from the system controller  101 , the disc drive  103  reproduces V 13  video data from the address next following the V 9  video data of the disc  102 . 
     The system controller  101  writes the V 13  video data obtained by the disc drive  103  in the video reproducing buffer  123 . 
     On storage of the V 13  video data, the video reproducing buffer  123  transiently sets the empty flag F em  to ‘0’ to output the empty flag so set to the system controller  101 , for temporarily terminating the data transfer request for the system controller  101 . 
     Once the V 9  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until the outputting of the speech data A 2  to A 5  to the monitor  160  comes to a close, that is for a four-field period, as in the case of the parallel recording/reproducing mode for the recording/reproducing apparatus  100 . 
     Thus, during the three-field period, beginning from the next 1V, three fields of the V 9  video data are outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , while speech data A 3 , A 4  and A 5  are outputted to the monitor  160 . 
     Also, at an input timing of video signals during the V 29  period, during outputting of the four fields of the V 9  video data to the monitor  160 , the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, by way of controlling the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 29  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     When the V 9  video data have been outputted the monitor  160  during the four-field period, the system controller  101  controls the switches  202  and  203  to be set to the side of the field memory  124  and to the side of the video reproducing buffer  123 , respectively, and controls the companding circuit  201  to operate in the expansion mode. 
     The companding circuit  201  reads out and decodes the V 13  video data stored in the video reproducing buffer  123  in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . 
     The V 13  video data, decoded by the companding circuit  201 , is written in the field memory  124 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , under control by the system controller  101 , in a manner not shown. The V 13  video data is also allowed to pass through the field memory  124  and outputted via D/A converter  121 , switch  120  and output terminal I 1b  sequentially to the monitor  160 . 
     The expansion circuit  142  reads out and decodes A 6  speech data stored in the speech reproducing buffer  143  in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 . The A 6  speech data recorded in the expansion circuit  142  is outputted via D/A converter  141 , switch  140  and output terminal I 1d  sequentially to the monitor  160 . 
     If the V 13  video data has been written in the field memory  124 , data readout in the video reproducing buffer  123  or data writing in the field memory  124  is not performed until the outputting of the speech data A 6  to A 9  to the monitor  160  comes to a close, that is for a four-field period, as in the operation during the parallel recording/reproducing mode in the recording/reproducing apparatus  100 . 
     Thus, during the three-field period as from the next 1V, three fields of the V 5  video data is outputted to the monitor  160 , in synchronism with the vertical synchronization signals from the synchronization separation circuit  110 , at the same time as speech data A 7 , A 8  and A 9  are outputted to the monitor  160 . 
     Also, at an input timing of the V 33  video signals during the V 25  period, during the outputting of the four fields of the V 13  video data to the monitor  160 , the system controller  101  controls the switches  202  and  203  to be set to the side of the A/D converter  111  and to the side of the video recording buffer  113 , respectively, and controls the companding circuit  201  to operate in the compression mode. 
     The companding circuit  201  is synchronized to the vertical synchronization signals from the synchronization separation circuit  110  for encoding the V 33  video data supplied from the A/D converter  111  via switch  202  for writing the encoded data in the video recording buffer  113  via switch  203 . 
     When the reproducing operation for the speech data A 2  to A 9 , V 9  vide data and the V 13  video data comes to a close, as described above, the recording/reproducing apparatus  200  proceeds to the recording operation. 
     The above-described recording and reproducing operations are then carried out by the recording/reproducing apparatus  200  until ‘stop’ of the parallel recording/reproducing mode is commanded such as by key input by the user. 
     In the above-described recording/reproducing apparatus  200 , the timing of encoding the video signals is alternated with the timing of decoding the encoded video signals for carrying out the encoding of the video signals and the decoding of the encoded vide signals by a sole circuit, that is the companding circuit  201 , thus eliminating the necessity of separately providing the compression circuit and the expansion circuit as in the case of the conventional recording/reproducing apparatus. The result is that the recording/reproducing apparatus  200  can be reduced in cost. 
     As described above, the recording/reproducing apparatus  200  uses, as a second format comprised of plural blocks constituted by the speech not thinned out on the time axis and video thinned out on the time axis, such a format  100   b  comprised of speech data for 8 V followed by the video data for 2 V, and includes the field memory  124  for freezing the video data decoded by the companding circuit  201  on the output side of the expansion circuit  124 , so that the number of reproduced frames can be easily increased without increasing the number of accessing to the disc  102  during the parallel recording/reproducing mode. Thus the recording/reproducing apparatus  200  can produce a satisfactory playback picture even if the playback mode is the parallel recording/reproducing mode. 
     The format shown in FIG. 9B in the present embodiment is merely exemplary and is not intended for limiting the present invention. Specifically, the operation with 8 V as a division or the video of two fields in the format  100   b  as the second format is not limiting the present invention.