Abstract:
A data recording/reproduction apparatus and a data recording/reproduction method according to the invention can effectively and economically utilize the limited resource of hard discs when editing files by defining the editing points on a plurality of data recorded on a non-linearly reproducible recording medium.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to a data recording/reproduction apparatus and a data recording/reproduction method for editing a plurality of data recorded on a recording medium adapted to non-linear data reproduction by defining a plurality of editing points.  
           [0003]    2. Description of Related Background Art  
           [0004]    In recent years, the number of channels available for transmitting information in the form of electric signals has been remarkably increased with the advent of CATV (cable television). As a result, there is a strong demand for apparatus adapted to simultaneously record a number of different sets of audio/video data and/or reproduce such data from a single audio/video data recording/reproduction apparatus. To meet this demand, apparatus called video servers and adapted to record and reproduce audio/video data have been developed and widely marketed.  
           [0005]    A video server is typically connected to a number of large capacity hard disc drives adapted to non-linear data reproduction to make the total recording capacity amount to tens to hundreds of several gigabytes. Such a video server is suited to record a huge volume of data including audio data and video data. Particularly, with a video server, any selected audio data or video data can be accessed in a very short period of time so that it can advantageously be used as recording/reproduction apparatus applied to editing data.  
           [0006]    The video server maintains information for managing the locations where the files store in each hard disc are actually found and the information is used to manage the audio/video data recorded on the hard disc. Additionally, when the video server is used to edit audio/video data, it prepares file editing information that is referred to as VFL (virtual file list) and include continuous data length information. Thus, an editing operation proceeds as a VFL is prepared by means of the video server by specifying and retrieving file name information and continuous data length information. The video server simply reproduces the VFL without re-recoding the retrieved audio/video data on a hard disc during the editing operation and then reads the edited audio/video data from the related hard disc by referring to the VFL during the subsequent replay operation.  
           [0007]    Japanese Patent Application No. 7-320185 (Japanese Patent Application Laid-Open Publication No. 9-163310) and U.S. Pat. No. 5,841,740 disclose a technology on the VFL invented by the applicant of the present patent application.  
           [0008]    Now, the technology disclosed in the above patent documents will be described below.  
           [0009]    Assume that file A and file B, both containing audio and/or video data, are stored on a hard disc in a video server as shown in FIG. 1A. FIG. 1A is a schematic illustration of the address space on a hard disc. The file A is recorded continuously at addresses  170  through  230  on the hard disc, using a total of sixty addresses. On the other hand, the file B is recorded at addresses  80  through  130  and  230  through  330 . In other words, the file B is recorded discontinuously on the hard disc.  
           [0010]    In the video server, the information showing the location of each of the files recorded on the corresponding hard disc of the video server is stored in a predetermined memory. FIGS. 1B and 1C illustrate the file system information of the file A and that of the file B. The file system information of the video server includes file entries and record entries. Each file entry contains the file name and the pointer information for pointing the corresponding record entry. Each record entry contains the address of the head of each continuous recording area and the length of the continuous recording area from the head.  
           [0011]    As shown in FIG. 1A and described above, the file A is recorded continuously at addresses  170  through  230  on the hard disc, using a total of sixty addresses. Since the file A is not recorded in any other area, the file system information of the file A includes a file entry containing the fine name “A” and the pointer information for pointing the corresponding record entry and a record entry containing the location of the head, or address “ 170 ”, the continuous recording area for “60” addresses starting from there and “END” indicating that the file A is not stored in any other area.  
           [0012]    Also as shown in FIG. 1A and described above, the file system information of the file B that is stored discontinuously on the hard disc includes a file entry containing the file name “B” and the pointer information for pointing the corresponding record entry and a record entry containing the location of the head, or address “ 80 ”, the continuous recording area for “50” addresses starting from there, the location of the next head, or address “ 230 ”, the continuous recording area for “100” addresses starting from there and “END” indicating that the file B is not stored any other area.  
           [0013]    The files recorded in the video server are then managed by means of the file system information and, for instance, a replay instruction specifying a file is input from the host, the video server confirms the address value to be accessed by using the file system information so that it can actually access the file stored on a specific hard disc and reproduce the data of the file.  
           [0014]    Now, an operation of editing some of the files stored in the video server by using an editing machine connected to the video server on the basis of the file system will be discussed below. Assume that the editing operation consists in connecting part of the file A and part of the file B to produce a new file.  
           [0015]    Firstly, both the file A and the file B are reproduced from the video server and sent to the editing machine. Assume here that the position at the 10-th address as counted from the head of the file A is the replay starting point (IN point) and the position at the 50-th address as counted form the head of the file A is the replay ending point (OUT point) of the file A, whereas the position at the 20-th address as counted from the head of the file B is the replay starting point (IN-point) and the position at the 60-th address as counted from the head of the file B is the replay ending point (OUT-point) of the file B. Then, the editing machine edits the files A and B by following a predetermined editing sequence.  
           [0016]    When the editing machine completes the operation of editing the two files, it sends the file of audio and/or video data produced as a result of the editing operation back to the video server. A VFL shows the data indicating the outcome of the editing operation.  
           [0017]    A VFL will be described by referring to FIGS. 2A and 2B.  
           [0018]    As shown in FIGS. 2A and 2B, the VFL shows the file names and the replay starting position and the replay ending position of each of the files. The replay stating position and the replay ending position are indicates by the respective address values obtained by defining the address of the head of the file as address  0 . It will be seen that FIGS. 2A and 2B show the VFL for the file A and the file B.  
           [0019]    Upon receiving the VFL as input, the video server prepares file system information (on file name “X”) independently from the above described file system information.  
           [0020]    More specifically, since the head position of the file A is known to be as “170” from the file system information on the file A as shown in FIG. 1B, the actual IN-point on the hard disc is 170+10, or “180”. As data are recorded continuously for an area corresponding to 40 addresses (=50−10), the continuous recording area is “40”. On the other hand, the head position of the file B is known to be as “100” from the file system information on the file B and data are recorded for an area corresponding to 40 addresses from the VFL. However, the data are recorded only continuously down to address “ 130 ” so that the data corresponding to 10 addresses are not found there because the head position is “100”. Then, the next continuous area starts from “ 230 ” and therefore all the data from the IN-point to the OUT-point can be reproduced by adding the data for “10” addresses starting from address “ 230 ”. Thus, the file system information on the file “X” obtained by the editing operation will be like the one shown in FIG. 2B.  
           [0021]    Note that “ON” or “OFF” may be shown in the bottom row of each file entry to represents an erasable flag. However, since the files have to be erased after the editing operation, “OFF” is actually shown at the bottom of each file entry.  
           [0022]    With the above arrangement, when reproducing the file obtained by the editing operation from the video server, it is now possible to reproduce the file on the basis of the file system information on the file “X”.  
           [0023]    Now, when editing files by means of the video server, it is possible to use a technique of special effects to the video data (to be referred to as video effects) near the IN-point from which a file is selected and the OUT-point at which the selection of the file ends according to the intension of the editor.  
           [0024]    However, when realizing such video effects, conventionally, it is necessary to read the two files, if two files are involved, from the hard disc by way of different respective ports, processing the files for the video effects and then recording them on the hard disc or some other hard disc before they are reproduced. Therefore, with the conventional editing technique involving the video effects, the files subjected to the operation of processing them for the video effects need to be recorded repeatedly on the hard discs to consume the limited resource of hard discs.  
         SUMMARY OF THE INVENTION  
         [0025]    In view of the above identified problem, it is therefore the object of the present invention to provide a data recording/reproduction apparatus and a data recording/reproduction method that can effectively and economically utilize the limited resource of hard discs when editing files involving video effects.  
           [0026]    In the first aspect of the invention, the above object is achieved by providing a data recording/reproduction apparatus provided with a plurality of input/output means for inputting and outputting data including video data and audio data and adapted to record data including video data and audio data input through said input/output means on a plurality of pieces of recording medium non-linearly accessible in allocated time slots and reproduce and output through said input/output means any of the data recorded on said recording medium including video data and audio data, said apparatus comprising:  
           [0027]    a recording/reproduction means for recording material data input through said input/output means on said recording medium and reproducing and outputting through said input/output means any of said material data from said recording medium;  
           [0028]    a first editing means for generating a first piece of editing information on the selection of editing points including a starting point and an ending point of a predetermined storage area storing a first material data and a starting point and an ending point of a predetermined storage area storing a second material data to be inserted in said first material data and the actual insertion of said second material data in said first material data;  
           [0029]    a video effect processing means for processing the video data in the vicinity of each of said editing point for predetermined specific video effects;  
           [0030]    a video-effect-processed data extracting means for extracting the data processed for the video effects by said video effect processing means;  
           [0031]    a recording control means for controlling said recording/reproduction means so as to record said video-effect-processed data extracted by said video-effect-processed data extracting means on said recording medium;  
           [0032]    a second editing means for inserting said video-effect-processed data recorded by said recording/reproduction means in said first material data and generating a second piece of editing information for inserting said second material data as modified by the insertion of said video-effect-processed data in said first material data;  
           [0033]    a virtual file generating means for generating a first virtual file describing the recording area of said first material data on said recording medium on the basis of the first piece of editing information generated by said first editing means, a second virtual file describing the recording area of said second material data on said recording medium on the basis of the second piece of editing information generated by said second piece of editing information and a third virtual file describing the recording area of said video-effect-processed data on said recording medium; and  
           [0034]    a reproduction control means for control said recording/reproduction means so as to reproduce the first material data, the second material data and the video-effect-processed data recorded on said recording medium on the basis of the first virtual file, the second virtual file and the third virtual file generated by said virtual file generating means.  
           [0035]    In the second aspect of the invention, the above object is achieved by providing a data recording/reproduction method adapted to use a plurality of input/output means for inputting and outputting data including video data and audio data so as to record data including video data and audio data input through said input/output means on a plurality of pieces of recording medium non-linearly accessible in allocated time slots and reproduce and output through said input/output means any of the data recorded on said recording medium including video data and audio data, said method comprising steps of:  
           [0036]    selecting editing points including a starting point and an ending point of a predetermined storage area storing a first material data and a starting point and an ending point of a predetermined storage area storing a second material data to be inserted in said first material data;  
           [0037]    processing the video data in the vicinity of each of said editing point for predetermined specific video effects;  
           [0038]    extracting the video-effect-processed data processed for the video effects;  
           [0039]    recording said extracted video-effect-processed data extracted on said recording medium;  
           [0040]    generating a first virtual file describing the recording area of said first material data on said recording medium, a second virtual file describing the recording area of said second material data on said recording medium and a third virtual file describing the recording area of said video-effect-processed data on said recording medium; and  
           [0041]    reproducing the first material data, the second material data and the video-effect-processed data recorded on said recording medium on the basis of the first virtual file, the second virtual file and the third virtual file generated by said virtual file generating means.  
           [0042]    Thus, a data recording/reproduction apparatus and a data recording/reproduction method according to the invention can effectively and economically utilize the limited resource of hard discs when editing files involving the video effects. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0043]    [0043]FIG. 1A is a schematic illustration of an address space on a hard disc.  
         [0044]    [0044]FIG. 1B is a schematic illustration of the file system information of file A in FIG. 1A.  
         [0045]    [0045]FIG. 1C is a schematic illustration of the file system information of file B in FIG. 1A.  
         [0046]    [0046]FIG. 2A is a table of VFL values including file names, reproduction starting points and reproduction ending points.  
         [0047]    [0047]FIG. 2B is another table of VFL values including file names, reproduction starting points and reproduction ending points.  
         [0048]    [0048]FIG. 3 is a schematic block diagram of an embodiment of A/V server, illustrating its configuration.  
         [0049]    [0049]FIG. 4 is a schematic illustration of an editing operation of inserting a second material data in a first material data and processing the data at an IN point for predetermined specific video effects, using the A/V server of FIG. 3.  
         [0050]    [0050]FIG. 5 is a flow chart of an editing operation involving a video effect, using the A/V server of FIG. 3.  
         [0051]    [0051]FIG. 6 is a flow chart of an operation of reproducing a VFL for a preview, using the A/V server of FIG. 3. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0052]    Now, the present invention will be described by referring to the accompanying drawings that illustrate preferred embodiments of the invention.  
         [0053]    The present invention is typically applied to an A/V (audio/video) server having a configuration as shown in FIG. 3. The A/V server  1  is adapted to record audio/video data (to be referred to as A/V data hereinafter) on a recording medium and reproduce A/V data therefrom (to be referred to as recording/reproduction hereinafter). In addition to recording/reproducing A/V data, the A/V server  1  can be used to edit A/V data by the user by operating a control panel as will be described hereinafter.  
         [0054]    The A/V server  1  comprises a recording port  10 , reproduction ports  20 ,  30 ,  40 , an editing manager  50 , a video effecter  60 , a control panel  70 , a timing manager  80 , a file manager  90  and an HDD array  10  comprising as recording medium a plurality of HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n  (n representing an integer).  
         [0055]    The A/V server  1  additionally comprises a data bus  120  for transferring data between the ports including the recording port  10  and the reproduction ports  20 ,  30 ,  40  and the HDD array  110  and a control bus  121  for transferring control data to be used for controlling the components. Thus, the A/V server  1  comprises a total of four input/output processing systems including an input processing section and three output processing sections.  
         [0056]    The recording port  10  operates as input processing section for recording the signals input through input terminal  18  on the HDD array  110 . The recording port  10  comprises a data input/output section  11  and a data management section  12 . The data input/output section  11  has a selector  13  and an encoder  14 , while the data management section  12  has a serial/parallel converter section (to be referred to as S/P hereinafter)  15 , a buffer  16  and CPU  17 .  
         [0057]    The selector  13  is used to select data for encoding. More specifically the selector  13  selects either data including audio/video data such as data adapted to SDIs (serial digital interfaces) conforming to SMPTE (Society of Motion Picture and Television Engineers)-259 and those adapted to SDTIs (serial digital transfer interfaces) conforming to SMPTE-305M that are input through the input terminal  18  or data output from the editing section  51  of the editing manager  50  and outputs them to the encoder  14  that is arranged downstream relative to the selector  13 .  
         [0058]    The encoder  14  encodes the signals output from the selector  13  in a predetermined format. More specifically, the encoder  14  processes the input signals for compression coding according to the MPEG (Moving Picture Experts Group) system. Note, however, that the encoder  14  operates not only for compression coding but also for transforming them in a format adapted for recording on any of the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n . Therefore, for example, it may extract audio signals and/or video signals from the data adapted to SDIs and/or audio signals and/or video signals from the data adapted to SDTIs. In the following description, the encoder  14  operate to process input signals for compression coding before outputting them. The compressed data produced by the encoder  14  as a result of compression coding are then input to the S/P  15  of the data management section  12 .  
         [0059]    The S/P  15  of the data management section  12  performs serial/parallel conversion on the compressed data input from the encoder  14  so that they may be written on any of the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n . The data obtained by the serial/parallel conversion of the S/P  15  are then fed to the downstream buffer  16 .  
         [0060]    The buffer is used to temporarily store the data output from the S/P  15  and sends them to the data bus  120  on a time-division multiplex basis. Although not shown, the buffer  16  is adapted to store individually the data output from the S/P  15 . The buffer  16  is also adapted to input data from the S/P  15  on an ad hoc basis and, as a time slot from timing pulse generator  81 , which will be described hereinafter, is assigned to the CPU  17 , it outputs the data it buffers to the data bus  120  in the time slot within a permitted period of time under the control of the CPU  17 .  
         [0061]    The data bus  120  that of the type referred to as SBX (Spydar Bus eXtension) and, although not shown, comprises an uplink bus for transmitting data in the sense of data recording and a downlink bus for transmitting in the sense of data reproduction. Each of the uplink bus and the downlink bus by turn has a plurality of buses so that the parallel data obtained from the corresponding serial data as a result of the serial/parallel conversion of the S/P  15  may be transmitted individually. Thus, the data output from the buffer  16  are transmitted to the HDD array  110  by way of the corresponding respective buses of the data bus  120 . Additionally, although not shown, an output processing section is arranged downstream relative to the buffer  16  so that each of the data output from the buffer  16  is multiplexed with a command for writing the data on any of the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100  according to the transmission format of the data bus  120 .  
         [0062]    The CPU  17  operates to control the operational sections of the recording port  10  on the basis of the control signal, which may be an external command, transmitted from the control panel  70 , which will be described in greater detail hereinafter, by way of the control bus  121 . If necessary, the CPU  17  transfers the control signal given to it to the CPU  53  of the editing manager  50 . Additionally, the CPU  17  controls the output of any of the data held by the buffer  16  on the basis of the time slot assigned to it by the timing pulse generator  81 .  
         [0063]    The recording port  10  having the above described configuration is adapted to receive video data and audio data as input.  
         [0064]    The reproduction port  20 , on the other hand, operates as output processing section for processing any of the data recorded in the HDD array  110  when outputting it externally. It comprises a data management section  21  and a data input/output section  22 .  
         [0065]    The data management section  21  by turn comprises a buffer  23 , a parallel/serial converter section (to be referred to as P/S hereinafter)  24  and a CPU  25 , whereas the data input/output section  22  comprises a decoder  26  and a selector  27 .  
         [0066]    The buffer  23  is used to temporarily store the data transmitted thereto from the HDD array  110  by way of the data bus  120 . Although not shown, the buffer  23  is adapted to store individually the data output in parallel from the HDD array  110 . As a time slot from the timing pulse generator  81  is assigned to the CPU  25 , the buffer  23  reads and input data from the HDD array  110  under the control of the CPU  25 .  
         [0067]    Each of the data output from the HDD array  110  is multiplexed with a status for the command for writing data on any of the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n  according to the transmission format of the data bus  120 . The data are then divided and transmitted respectively by way of the plurality of buses of the downlink bus of the data bus  120 . With this arrangement, the A/V server  1  is made relatively free from factors that can give rise to errors such as collisions of data of the input system and those of the output system and adapted to record and reproduce data simultaneously as data are transmitted data on the basis of the time slot assigned to it. The data input to the buffer  23  are buffered there and then fed to the downstream P/S  24 .  
         [0068]    The P/S  24  transforms the parallel data input form the buffer  23  into serial data. The serial data obtained by the P/S  24  as a result of parallel/serial conversion are then fed to the decoder  26  of the data input/output section  22 .  
         [0069]    The CPU  25  operates to control the operational sections of the reproduction port  20  on the basis of the control signal transmitted from the control bus  121 . If necessary, the CPU  25  transfers the control signal given to it to the CPU  53  of the editing manager  50 . Additionally, the CPU  25  operates to obtain the right of use of the data bus  120  on the basis of the time slot assigned to it and input the related data to the buffer  23 .  
         [0070]    The decoder  26  of the data input/output section  22  operates to decode the serial data input from the P/S  24  by performing a predetermined processing operation on the data for decoding. If the data reproduced from any of the HDDs  100  are compressed, the decoder  26  expands them and transforms them typically into SDI data before outputting them. The data including video data and audio data obtained as a result of a decoding operation of the decoder  26  are input to the selector  27  and the editing section  51  of the editing manager  50 .  
         [0071]    The selector  27  selects the signals to be output externally by way of the output terminal  28 . More specifically the selector  27  selects either the data output from the decoder  26  or the data output from the editing section  51  of the editing manager  50  and supplies them to the output terminal  28  as SDI data or SDTI data.  
         [0072]    The reproduction port  20  having the above described configuration is adapted to output video data and audio data for 4 channels or 8 channels.  
         [0073]    Both the reproduction ports  30  and  40  have a configuration similar to that of the reproduction port  20 .  
         [0074]    More specifically, the reproduction port  30  comprises a data management section  31  and a data input/output section  32 . The data management section  31  by turn comprises a buffer  33  for temporarily storing the data from the HDD array  110 , a P/S  34  for transforming the parallel data from the buffer  33  into serial data and a CPU  35  for controlling the components of the reproduction port  30 . On the other hand, the data input/output section  32  comprises a decoder  36  for decoding the serial data input from the P/S  34  and a selector  37  for selecting either the data output from the decoder  36  or the data output from the editing section  51  and supplies them to the output terminal  38 .  
         [0075]    On the other hand, the reproduction port  40  comprises a data management section  41  and a data input/output section  42 . The data management section  41  by turn comprises a buffer  43  for temporarily storing the data from the HDD array  110 , a P/S  44  for transforming the parallel data from the buffer  43  into serial data and a CPU  45  for controlling the components of the reproduction port  40 . On the other hand, the data input/output section  42  comprises a decoder  46  for decoding the serial data input from the P/S  44  and a selector  47  for selecting either the data output from the decoder  46  or the data output from the editing section  51  and supplies them to the output terminal  48 .  
         [0076]    The editing manager  50  comprises an editing section  51 , an interface (I/F)  52  and a CPU  53  and operates to output the data input from the above described recording port  10  and reproduction ports  20 ,  30 ,  40  to the video effecter  60 , which will be described in greater detail hereinafter, by way of the editing section  51  so that the latter may edit the data. Additionally, the editing manager  50  outputs the data from the video effecter  60  to the selector  13  of the recording port  10  and the selectors  27 ,  37 ,  47  of the reproduction ports  20 ,  30 ,  40 .  
         [0077]    The editing section  51  selects the data it needs out of the data input from the recording port  10  and the data coming from the decoders  26 ,  36 ,  46  of the reproduction ports  20 ,  30 ,  40  typically by means of the selector (not shown) provided therein and outputs the selected data to the video effecter  60 . The editing section  51  also outputs the data input from the video effecter  60  to the one of the ports or the CPU  53  by selecting the right destination of the data by means of the selector (not shown) provided therein. Additionally, if the editing section  51  outputs the data input from the recording port  10  and the data coming from the decoders  26 ,  36 ,  46  of the reproduction ports  20 ,  30 ,  40  to an external monitor, it does so by supplying the data to the output terminal  54 .  
         [0078]    The I/F  52  is connected to the control panel  70 , which will be described in greater detail hereinafter, and outputs the control signal for controlling the control panel  70  and the A/V data input from the CPU  53  to the control panel  70 . It also inputs the operation input signals it receives from the control panel  70  to the CPU  53 . Additionally, the I/F  52  is connected typically to an external VTR (video tape recorder) to output various commands and also receives various external commands.  
         [0079]    The CPU  53  controls the CPU  17  of the recording port  10  and the CPUs  25 ,  35 ,  45  of the reproduction ports  20 ,  30 ,  40  by executing the editing execution primary stored in the inside.  
         [0080]    The CPU  53  that controls the CPUs of the ports simultaneously also operates to output control signals for reading any of the A/V data stored in the HDDs  100 , to the HDD array  110  and inputs A/V data. For this operation, the CPU  53  displays the breakdown of the editing operation by reading the material data to be edited according to the VFL and outputting the data to the control panel  70  by way of the I/F  52 .  
         [0081]    Additionally, the CPU  53  operates for previewing according to the VFL generated by the editing operation in response to an operation input signal for the preview coming from the control panel  70 . For this purpose, the CPU  53  reads the VFL stored in the file management section  91  and then the A/V data that the VFL indicates sequentially from the HDDs  100  by way of any of the ports  20  through  40  and outputs them to the control panel  70  by way of the I/F  52 .  
         [0082]    The video effecter  60  processes the data for specific video effects, utilizing the plurality of ports  20  through  40 . More specifically, the video effecter  60  processes the data input from the editing manager  50  for a specific effect such as an effect of picture-in-picture for generating a new time series data by inserting a material data to another material data and connects them together.  
         [0083]    The control panel  70  comprises various switches to be operated by the user for selecting the data to be edited and the port to be used for inputting/outputting data and a display section for displaying the images to be used for the editing operation. As the control panel  70  is operated by the user, it generates operation input signals corresponding to the user operation.  
         [0084]    The timing manager  80  manages the data bus  120  with timings determined on the basis of video synchronizing signals. The timing manager  80  comprises a timing pulse generator  81  for generating timing pulses, an interface (I/F)  82  operating as interface for connecting the control panel  70  and the timing manager  80  and a CPU  83  for controlling the components of the timing manager  80 .  
         [0085]    In the timing manager  80 , the CPU  83  controls the timing pulse generator  81  so as to make it generate a timing pulse according to an externally input video synchronizing signal and transmit it to the control bus  121 . The timing manager  80  manages the right of use of the data bus  120  according to the timing pulse.  
         [0086]    The file manager  90  comprises a file management section  91  for holding file management information indicating the storage areas of the files in the HDDs  100  as will be discussed hereinafter and managing files according to the file management information it holds, a network driver  92  connected to external networks such as Ethernet to input data from and output data to the external networks and a CPU  93  for controlling the components of the file manager  90 .  
         [0087]    The file manager  90  manages the data recorded in the HDD array  110  as will be discussed hereinafter under the control of the CPU  93 . For instance, when a file is recorded in one of the HDDs  100 , the file manager  90  manages the file recorded in the HDD array  110  by using the file management information including the information showing the address in the HDDs  100  where the file is recorded.  
         [0088]    The file management section  91  is also adapted to control the HDD array  110  so as to reproduce any necessary file therefrom simply by specifying the file name of the file in response to the operation input signal applied to it and reproduce material data according to the result of the editing operation on the basis of the virtual files without recording any new data at the time of the editing operation.  
         [0089]    The HDD array  110  stores various data in the HDDs  100  and manages the data stored there. The HDD array  110  is connected to the plurality of HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n  so as to store various data in the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n  and manage the data stored in the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 ,  100   n-1  and  100   n . The HDD array  110  comprises a buffer  111 , a video data write/read processing section (V)  112  and an audio data write/read processing section (A)  113 .  
         [0090]    The buffer  111  temporarily stores data when transferring the data between itself and the data bus  120 . For example, the data coming from the HDDs  100  are buffered in the buffer  111  before they are output to the data bus  120 .  
         [0091]    The video data write/read processing section  112  operates for writing video data to and reading video data from the HDDs  100  connected to it. More specifically, the video data write/read processing section  112  selects the right HDD  100  out of the HDDs  100  to write the video data input from the buffer  111  on it or read the necessary audio data from the HDD  100  in order to output them to the buffer  111 .  
         [0092]    The audio data write/read processing section  113  operates for writing audio data to and reading audio data from the HDDs  100   n-1  and  100   n  connected to it. More specifically, the audio data write/read processing section  113  selects the right HDD  100  out of the HDDs  100   n-1  and  100   n  to write the audio data input from the buffer  111  on it or read the necessary audio data from the HDD  100  in order to output them to the buffer  111 .  
         [0093]    The HDD array  110  is provided with a certain extent of redundancy to show a structure of so-called RAID (Redundant Array of Inexpensive Discs) so that the data to be recorded may be written thereto reliably and the data to be reproduced may be reliably read therefrom. The HDDs  100   1 ,  100   2 , . . . ,  100   n-3  and  100   n-2  are made to show an enhanced level of data transfer performance as they show a RAID structure in order to transfer data in parallel by dividing the data for a plurality of discs and also have a parity disc. Of the HDDs  100 , the HDDs  100   n-1  and  100   n  for storing audio data show a structure of RAID-1 or so-called mirror disc with which data are written in duplicate.  
         [0094]    Now, the processing operation of the A/V server  1  for recording the externally input data on the HDDs  100  will be discussed below.  
         [0095]    The data input to the input terminal  18  of the A/V server  1  are sent to the encoder  14  by way of the selector  13  of the data input/output section  11  of the recording port  10  and encoded in a predetermined format by the encoder  14 . The encoded data are then transformed into parallel data by the S/P  15  of the data management section  12  of the recording port  10  and buffered by the buffer  16 . The buffered data are then output to the data bus  120  in the time period of the time slot assigned to the CPU  17  by the timing pulse generator  81  and transferred to the HDD array  110 .  
         [0096]    The data transferred to the HDD array  110  are then buffered by the buffer  111  and read out from the latter. Of the data read out from the buffer  111 , the video data are input to the video data write/read processing section  112 , whereas the audio data are input to the audio data write/read processing section  113 . The video data write/read processing section  112  divides the input video data by a predetermined unit and determines the parity thereof. Then, it stores the divided data and the obtained parity data in the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2 . On the other hand, the audio data write/read processing section  113  stored the input audio data in the two HDDs  100   n-1  and  100   n . At this time, the file management section  91  generates new file management information including file names and the addresses of the storage areas of the HDDs  100  storing the data according to the stored data.  
         [0097]    Thus, the A/V server  1  can record the externally input data in the HDD array by carrying out the above described processing operation.  
         [0098]    Now, the processing operation of the A/V server  1  for reproducing any of the data stored in the HDDs  100  and outputting them to the reproduction ports  20  through  40  will be discussed below.  
         [0099]    In the A/V server  1 , one of the reproduction ports  20 ,  30 ,  40  accesses the HDD array  110  in the time slot assigned by the timing pulse generator  81  and requests the HDD array  110  to reproduce the necessary data. Then, the video data write/read processing section  112  of the HDD array  110  reads the video data that are divided and stored in the HDDs  100   1 ,  100   2 , . . . ,  100   n-3 ,  100   n-2  along with the parity data also stored there. Then, it unifies the divided data and performs an error detecting/error correcting operation by referring to the parity data to reproduce the video data. On the other hand, the audio data write/read processing section  113  of the HDD array  110  reads the audio data from the HDD of the two HDDs  100   n-1  and  100   n  that is free from errors. At this time, the video data write/read processing section  112  and the audio data write/read processing section  113  access the files from which the data are reproduced by referring to the file management information stored in the HDDs  100  or the file management section  91 . The reproduced audio/video data are then buffered by the buffer  111  and subsequently read out so as to be transferred to the reproduction port that issued the request for the reproduction by way of the data bus  120 .  
         [0100]    In the above described processing operation of the A/V server  1  for reproducing data, if the reproduction port  20  issues a request for data reproduction, the data output from the HDD array  110  are input to the buffer  23  of the data management section  21  by way of the data bus  120 . The data input to the buffer  23  are then buffered by the buffer  23  and transformed into serial data by the P/S  24 . The obtained serial data are then input to the decoder  26  of the data input/output section  22  and decoded by it before being fed to the output terminal  28  by way of the selector  27  and externally output. In this way, the A/V server  1  can reproduce internal materials and output them to the outside.  
         [0101]    Now, the operation of the A/V server  1  for editing the externally input data and/or the material data stored in the HDDs  100  will be discussed below.  
         [0102]    The A/V server  1  starts an processing operation for editing data according to an operation input signal that is generated by the user operating any of the appropriate buttons arranged on the front surface of the control panel  70 . More specifically, the CPU  303  of the control panel  70  defines the IN-point of the time of the starting point from which the operation of editing each of the material data to be edited starts and the OUT-point of the time of the ending point at which the operation of editing the material data ends.  
         [0103]    Additionally, the A/V server  1  holds the file system information managed by the above described file management section  91  so that it can reproduce any desired file simply by specifying the file name of the file and can reproduce any internal material according to the outcome of the editing operation without recording the newly prepared data on the basis of the virtual files containing information on the files from which data are reproduced.  
         [0104]    More specifically, the A/V server  1  can access any given address of any of the HDDs  100  according to the VFLs and output the necessary editing data on the basis of the VFLs by sequentially reading the recorded material data to the control panel  70  so that the output data may be displayed to the user. In other words, when the A/V server  1  is operating for editing data, it is not required to store the edited data in the HDDs  100 . Therefore, the A/V server  1  can use the storage areas of the HDDs  100  in a highly efficient and economic way.  
         [0105]    For instance, the A/V server  1  will perform an operation of processing the edited data  203  obtained by using first material data  201  that are video data and second material data  202  that are also video data for video effects and record the area indicated by “(7)” in the HDD array  110  as shown in FIG. 4 when reproducing the outcome of the editing operation for previewing.  
         [0106]    The edited data  203  of FIG. 4 are obtained by inserting the second material data  202  into the area of the first material data  201  starting from the IN-point and ending at the OUT-point. Now, the area of the first material data  201  down to the IN-point is referred to as area “(1)” and the area between the IN-point and the OUT-point and the area after the OUT-point are referred to respectively as area “(2)” and area “(3)”, whereas the area of the second material data  202  down to the IN-point is referred to as area “(4)” and the area between the IN-point and the OUT-point and the area after the OUT-point are referred to respectively as area “(5)” and area “(6)”. The edited  203  is obtained by editing the first material data  201  and the second material data  202 . The edited data  203  contains the area “(1)” and the area “(3)” of the first material, the area “(7)” processed for video effects and the area “(5)” of the second material data obtained by removing the above area “(7)” from the area “(5)” of the second material.  
         [0107]    Now, the editing operation involving the processing operation for video effects and using the first material data  201  and the second material data  202  that are internal data recorded in the HDD array  110  of the A/V server  1  will be described by referring to the flow chart of FIG. 5.  
         [0108]    Assume here that the first material data  201  and the second material data  202  are used to generate a VFL file for previewing and the first material data  201  are read from the HDD array  110  to the reproduction port  30  while the second material data  202  are read from the HDD array  110  of the A/V server  1  to the reproduction port  40  so that the edited data  203  may be output from the output terminal  54 .  
         [0109]    Firstly, in Step S 1 , the editing operation starts in response to the input from the control panel  70  and the IN-point and the OUT-point of the first material data  201  and the IN-point and the OUT-point of the second material data  202  are selected. Additionally, the level and other parameters of each video effect is determined by the control panel  70  at each IN-point.  
         [0110]    Then, in Step S 2 , the CPU  53  controls the file management section  91  to make the latter prepare a VFL file for previewing by using the IN-points, the OUT-points and the parameters of the video effects selected in Step S 1 .  
         [0111]    In Step S 3 , the CPU  53  reproduces the areas defined by the editing points (the IN-points and the OUT-points) and the areas processed for video effects of the first material data  201  and the second material data  202  to output the image prepared on the basis of the VFL file for previewing. If the material data are processed for video effects at any of the editing points, the image data for the related area are output to the recording port  10  and recorded in the HDD array  110  so as to generate a new VFL file corresponding to the storage areas of the HDD array  110  storing the image data obtained by performing the processing operation for video effects.  
         [0112]    Now, the processing operation that is performed to reproduce the VFL file for previewing prepared in Step S 3  will be discussed by referring to the flow chart of FIG. 6.  
         [0113]    Firstly, in Step S 11 , the first material data as shown in FIG. 4 are read out to the reproduction port  30  from the HDD array  110  by way of the data bus  120  and, at the same time, the second material data also shown in FIG. 4 are read out to the reproduction port  40  from the HDD array  110  by way of the data bus  120 . The first material data  201  read to the reproduction port  30  are then decoded by the decoder  36  and input to the editing section  51  of the editing manager  50 . The second material data  202  read to the reproduction port  40  are decoded by the decoder  46  and input to the editing section  51  of the editing manager  50 . The CPU  53  controls the operation so as to make the first material data input to the editing section  51  to be displayed on the monitor screen from the output terminal  54  until the IN-point comes on the basis of the VFL file for previewing.  
         [0114]    Then, in Step S 12 , the first material data  201  and the image data starting from the IN-point of the second material data  202  are sent to the video effecter  60  from the editing section  51 . The video effecter  60  performs a processing operation on the first material data  201  and the second material data  202  that are sent to it for video effects typically including that of dissolving the two sets of material data by fading out the first material data and fading in the second material. However, it may be appreciated that video effects that can be used in this step are not limited to dissolving but a variety of video effects including wiping, fading in and fading out may be used for the purpose of the invention. The image data processed for video effects are then sent back to the editing section  51 .  
         [0115]    In Step S 13 , the editing section  51  outputs the image data that have been processed for video effects from the output terminal  54  according to the VFL file for previewing under the control of the CPU  53 . Additionally, the CPU  53  of the editing section  51  outputs the image data processed for video effects and sent from the video effecter  60  to the recording port  10 . At the same, the CPU  53  controls the file management section  91  so make it generate a VFL file for the image data processed for video effects and a VFL file for the second material data that have been modified as a result of having been subjected to a processing operation for video effects. The generated VFL files are then stored in the memory contained in the file management section  91  or in the HDDs  100  as the outcome of the editing operation.  
         [0116]    Then, in Step S 14 , image data that have been processed for video effects and output from the editing section  51  to the recording port  10  are processed at the recording port  10  as ordinary image data and then recorded in the HDD array  110 .  
         [0117]    Thereafter, in Step S 15 , the CPU  53  controls the editing section  51  on the basis of the VFL files for previewing to make it output the second material data following the image data processed for video effects and the first material data from the output terminal  54 .  
         [0118]    With the above described processing operation, the image data processed for video effects are recorded in the HDD array  110  and VFL files are generated. The generated VFL files indicate the recording areas of the HDD array  110  corresponding to the area “(1)”, the area “(7)”, the area “(5)” and the area “(3)” shown in FIG. 4. Thus, the file management section  91  of the A/V server  1  can output the outcome of the editing operation by reproducing the image data processed for video effects and recorded in the HDD array  110  along with the first material data and the second material data from the HDD array  110  according to the generated VFL files.