JPH09284693A - Data recording and/or reproducing device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start reproduction with a fixed delay time after a reproduction start instruction is received by using a buffer memory for reproduction only. SOLUTION: A data recording and reproducing device 10 is provided with a buffer memory 32 with two buffers between an external input output terminal 35 and a data storage device 30 that records video and/or audio data files to a recording medium accessed at random and reproduces the recorded data file. A CPU 11 controls revision of a write adderss of the buffer making a write operation in the buffer memory 32 to a write start position to write newly a data amount equal to a data amount in a buffer making a read operation in response to the file reproduction instruction from on automatic drive controller 20. After the lapse of a fixed delay time equivalent to the buffer size after the reception of the file reproduction instruction, audio/video data of the file are read from the buffer memory 32 and outputted from the external input output terminal 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording and / or reproducing apparatus and method for recording audio and / or video data and reproducing the recorded audio and / or video data in response to a request from an external device. .

[0002]

2. Description of the Related Art For example, in a television broadcasting station, in an automatic driving apparatus for automatically reproducing a program or a commercial, it is necessary to continuously reproduce a plurality of audio / video signals. In such an automatic driving device, PLAY (reproduction), STOP of each audio / video data is performed from the automatic driving control device.
Commands such as (stop) are supplied in real time.

As a method for continuously reproducing a plurality of audio / video signals by the control as described above, two V
A method using a TR (video tape recorder) and an audio / video signal switching device is known. That is, one VTR
, And then CUEUP with the other VTR, that is, cue up and put it in a state where it can be immediately played back, and then play the next PLA.
When the Y command is received, the reproduction of the VTR in the CUEUP is started and the output is switched. A CUEUP VTR can start reproducing audio / video data with a fixed delay time ΔT of several frames. Therefore, the automatic driving control device can continuously reproduce a plurality of audio / video signals at a desired timing by generating the reproduction start signal earlier by the fixed delay.

Here, using the system having the configuration shown in FIG. 9, audio / video signals SA1 and SB as shown in FIG.
1, SA2, SB2 at time ts1, ts2, ts, respectively
Switching and reproduction at the timing of 3 and ts4 will be described.

The VTRs 91 and 92 shown in FIG.
If P is set, reproduction can be started with a predetermined fixed delay time T0. The selector 93, which is an audio / video signal switching device, can switch within the same frame in response to an input switching command. These VTRs 91,92
The selector 93 is controlled by the automatic driving control device 90. The automatic driving control device 90 performs CUEUP in advance for the control of the VTRs 91 and 92, and issues a reproduction command ahead of the desired reproduction time by the time T0. The control for the selector 93 issues a command at a desired switching time.

In the control of the VTRs 91 and 92 of FIG. 10, C is CUEUP, P is PLAY (playback), and S is STOP.
It shows the issuing of each command of (stop). This FIG.
The operation of the reproduction sequence shown in FIG. 11 will be described with reference to the flowcharts shown in FIGS.

First, in step ST201 of FIG. 11, the tape on which the audio / video signal SA1 is recorded is set to V
Insert into TR91. In step ST202, the tape on which the audio / video signal SB1 is recorded is set to VTR92.
To insert. In the next step ST203, the automatic driving control device 90 sends to the selector 93 a command [OUT = a] for selecting the input terminal a and connecting it to the output. Step ST2
In 04, the selector 93 selects the input from the input terminal a.

At the next step ST205, time t = t0
At this timing, the automatic driving control device 90 sends the CUEUP command to the VTR 91, and the VTR 91 performs the CUEUP in step ST206.

At the next step ST207, time t = t1
The automatic driving control device 90 sends the PLAY (playback) command to the VTR 91 at the timing of step ST2.
08, at time t = after the fixed delay time T0 has elapsed.
At ts1, the VTR 91 starts reproducing the audio / video signal SA1. After this time, as shown in step ST209, the audio / video signal SA1 is output from the selector 93.

In the next step ST210, time t = t2
At this timing, the automatic driving control device 90 sends the CUEUP command to the VTR 92, and in step ST211, the VTR 92 performs CUEUP.

At the next step ST212, time t = t3.
The automatic operation control device 90 sends the PLAY (playback) command to the VTR 92 at the timing of step ST2.
13, the time t = ts2 after the fixed delay time T0 has elapsed
Then, the VTR 92 starts reproduction of the audio / video signal SB1. At this time t = ts2, the automatic driving control device 90
As shown in step ST214, a command [OUT = b] for selecting the input terminal b and connecting it to the output is sent to the selector 93. In step ST215, the selector 93 selects the input from the input terminal b. Therefore, from this time ts2 onward, the selector 93 outputs the audio / video signal SB1 as shown in step ST216.

At the next step ST217, time t = t4.
The automatic driving control device 90 sends the STOP (stop) command to the VTR 91 at the timing of step ST2.
At 18, the VTR 91 stops reproduction.

Next, in step ST219, the tape on which the audio / video signal SA2 is recorded is inserted into the VTR 91. In the next step ST220, the automatic driving control device 90 causes the VTR 91 to perform the above C at the timing of time t = t5.
Send UEUP command, and VTR in step ST221
91 performs CUEUP.

Next, in step ST222 of FIG.
At the timing of time t = t6, the automatic driving control device 90 becomes V
The PLAY (playback) command is sent to TR91, and in step ST223, at time t = ts3 after the elapse of the fixed delay time T0, the VTR91 causes the audio / video signal SA to be transmitted.
Start playback of 2. At this time t = ts3, the automatic driving control device 90 sends a command [OUT = a] for selecting the input terminal a and connecting it to the output to the selector 93, as shown in step ST224. In step ST225, the selector 93 selects the input from the input terminal a. Therefore, from this time ts3 onward, as shown in step ST226,
The audio / video signal SA2 is output from the selector 93.

At the next step ST227, time t = t7.
The automatic driving control device 90 sends the STOP command to the VTR 92 at the timing of step ST2.
At 28, the VTR 92 stops playing.

Next, in step ST229, the tape on which the audio / video signal SB2 is recorded is inserted into the VTR 92. In the next step ST230, the automatic driving control device 90 causes the VTR 92 to perform the above-mentioned C at the timing of time t = t8.
Send UEUP command, and VTR in step ST231
92 performs CUEUP.

Next, in step ST232, time t =
At the timing of t9, the automatic driving control device 90 causes the VTR 92 to
Send the above PLAY command to step ST
233, at time t after the fixed delay time T0 has elapsed
= Ts4, the VTR 92 starts reproduction of the audio / video signal SB2. At this time t = ts4, the automatic driving control device 9
0 indicates the selector 93, as shown in step ST234.
A command to select the input terminal b and connect it to the output [OUT =
b] is sent. In step ST235, the selector 93 selects the input from the input terminal b. Therefore, this time ts4
From then on, as shown in step ST236, the audio / video signal SB2 is output from the selector 93.

At the next step ST237, time t = t1.
At the timing of 0, the automatic driving control device 90 causes the VTR 91 to
Send the above STOP command to step ST
At 238, the VTR 91 stops playing. Also step S
At T239, the automatic driving control device 90 sends the STOP (stop) command to the VTR 92 at the timing of time t = t11, and the VTR 92 stops the reproduction at step ST240.

[0019]

By the way, in recent years, a recording / reproducing apparatus for audio and / or video data using a recording / reproducing apparatus such as a HDD (hard disk device) capable of random access as a data accumulating apparatus has been considered. However, let us consider a case in which such a device is intended to perform control equivalent to that of a system composed of two VTRs and a selector for switching audio / video signals.

When data is reproduced by an audio / video data recording / reproducing device which uses a disk device such as an HDD as a storage device, the data from the disk device is a transfer rate necessary for reproducing the audio / video data. Faster but discontinuous data. On the other hand, a constant transfer rate is required to output audio / video data.

Therefore, control such as rate matching using a buffer memory or the like is required.
The CUEUP of the next audio and video data as done in R
The configuration for performing
It is difficult to perform control such that reproduction is started with a fixed delay time equivalent to UEUP.

The present invention has been made in view of such a conventional situation, and can output audio / video data at a constant transfer rate by using a data storage device capable of random access and has a simple structure. An object of the present invention is to provide a data recording and / or reproducing apparatus and method for starting reproduction after a fixed delay time has elapsed from the time of inputting a reproduction start command.

[0023]

According to the present invention, in order to solve the above-mentioned problems, video and / or audio data files are recorded on a randomly accessible recording medium and the recorded data files are reproduced. A buffer memory having two buffers is provided between the data recording / reproducing means and the external input / output terminal, and the write address of the buffer being written in the buffer memory is changed to the buffer being read in response to the file reproducing command. It is characterized in that change control is performed to a write start position for newly writing a data amount equal to the data amount of.

As a result, the audio / video data of the file is read out from the buffer memory and output after a fixed delay time corresponding to the buffer size has passed since the file playback command for the new audio / video data file was given. It

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention in which a random access data storage device which can be controlled by an automatic driving control device 20 and which records and reproduces audio and / or video data is used. Data recording / reproducing apparatus 1
FIG. 2 is a block diagram showing a system configuration of No. 0.

In FIG. 1, a data recording / reproducing apparatus 1
0 is connected to an automatic operation control device 20, which is a conventional PLAY (reproduction), RE
In addition to the C (record), CUEUP, and STOP (stop) commands, the OPEN and CLOSE commands are output. This is VT
While R manages the audio / video signal by the time code, in the system shown in FIG. 1, since the audio / video signal is managed by the file system, PL
This is because the OPEN and CLOSE of the file as the target of the AY, REC, CUEUP, and STOP instructions are necessary. The data recording / reproducing device 10 records a plurality of audio data and video data or any one of them (audio / video data), and outputs the audio / video data in response to a request from the automatic driving control device 20.

In the internal structure of the data recording / reproducing apparatus 10, a CPU (microprocessor unit) 11 and a CP
ROM (Read Only Me) that stores the U program
mory) 12, a RAM (Random Access Memory) 13, which serves as a work area for the CPU to execute a program, and CP which takes in input / output signals from the automatic operation control device 20.
A control signal interface circuit (control signal I / F circuit) 14 for transmitting to U and a file management information storage unit 15 such as a hard disk for storing file management information,
It is connected to the bus line 16. A computer for control is configured by these components, each component of the data recording / reproducing device 10 is controlled based on the edit data input from the automatic driving control device 20, and is recorded in the data storage device 30. It manages the recording area for each audio / video data. That is, the CPU (microprocessor unit) 11 is, for example, a general-purpose microprocessor or RISC (Reduced Instruction Set Co).
It is composed of a microprocessor and its peripheral circuits. The CPU 11 uses the RAM 13 to ROM1
2 executes the program stored in the control signal I /
The automatic driving control data and the response data are transmitted / received to / from the automatic driving control device 20 via the F circuit 14.

The data storage device 30 is a large-capacity random-access data recording / reproducing device such as a hard disk array device, and is connected to the bus line 16 such as an interface circuit (data storage I / F circuit) such as SCSI. ) 31 is used to input / output data. The data storage I / F circuit 31 inputs / outputs data from / to the buffer memory 32 connected to the bus line 16. The buffer memory 32 inputs and outputs data to and from the encoder / decoder 33, and is a buffer between a video / audio signal which is continuous data at a constant speed and data of the high-speed and intermittent data storage device 30. Do the ring. The encoder / decoder 33 performs compression / expansion of data as necessary, and outputs audio / video to / from an external input / output terminal 35 via an audio / video signal interface circuit (audio / video signal I / F circuit) 34. Inputting and outputting signals. The audio / video signal I / F circuit 34 extracts only data from the audio / video signal input from the outside, or conversely adds a synchronization signal or the like to the audio / video data and converts it into an audio / video signal. It should be noted that the encoder / decoder 33 is not necessary when handling the signal in a non-compressed state.

The CPU 11 of the data recording / reproducing apparatus 10 is
The data storage device 30 and the like are controlled via the data storage I / F circuit 31 in synchronization with a synchronization signal such as a reference signal of the broadcasting station, and the data storage is performed in response to a request from the automatic operation control device 20 and other external devices. The device 30 is caused to record audio / video data, and the recorded audio / video data is provided to the automatic driving control device 20 and other external devices. CPU1
1 generates recording area data or file management information indicating recording areas occupied by the audio / video data recorded in the data storage device 30 in the recording medium (hard disk or the like) of the data storage device 30. Also, C
The PU 11 generates recording area data of partial data or file management information indicating a recording area occupied by each portion (partial data) of audio / video data (material data) included in the edited result data in the recording medium of the data storage device 30. To do. Further, the CPU 11 stores the generated recording area data or file management information in the RAM 1
3 and the file management information storage unit 15 such as a hard disk.

Here, FIG. 2A shows the flow of data at the time of recording, and FIG. 2B shows the flow of data at the time of reproduction.

First, at the time of recording shown in FIG. 2A, the audio / video signal supplied to the external input / output terminal 35 is transmitted through the audio / video signal I / F circuit 34 to the encoder 33E (of the encoder / decoder 33). Sent to the encoder)
The data is compressed and sent to the buffer memory 32. The buffer memory 32 has a configuration as shown in FIG. 3, for example, and temporarily buffers audio / video data. This is because the data rate from the outside is different from the transfer rate and timing for accessing the data storage means. The audio / video data from the buffer memory 32 is sent to the data storage device 30 via the data storage I / F circuit 31 and recorded therein.

At the time of reproduction shown in FIG. 2B, the audio / video data recorded in the data storage device 30 is read out and sent to the buffer memory 32 via the data storage I / F circuit 31. . The audio / video data is temporarily buffered in the buffer memory 32, and the decoder 33D
Data is expanded in the (decoder section of the encoder / decoder 33) and taken out from the external input / output terminal 35 via the audio / video signal I / F circuit 34.

Next, regarding the buffer memory 32,
This will be described with reference to FIG. The buffer memory shown in FIG. 3 is an example of what is called a double buffer. That is, on the input (IN) side of the two buffers 41 and 42, a selector 44 is provided, which switches and selects the input data from the input terminal 43 and sends the data to either one of the buffers 41 and 42. Output (OU
A selector 45 is provided on the T) side to switch and select the output data from one of the buffers 41 and 42 and send it to the output terminal 46. The selected terminals of the selectors 44 and 45 on the buffer 41 side are all set to a, and the selected terminals of the buffer 42 side are set to b. Selector 4
The selector 4 selects one of the buffers 41 and 42 for writing and supplies the data from the input terminal 43.
Reference numeral 5 selects the other of the buffers 41 and 42 for reading and sends the read data to the output terminal 46. The write address of each buffer 41, 42 is generated from the write address generation circuit 47, and the read address is generated from the read address generation circuit 48.
The signals are supplied to the address terminals of the buffers 41 and 42 via the selector 49 composed of a crossbar switch.
That is, one of the read address supplied to the write address input terminal W of the selector 49 and the write address supplied to the read address input terminal R is connected to the address terminal of the buffer 41 via the output terminal a and the other. Are supplied to the address terminals of the buffer 42 via the output terminals b. The selectors 44, 45, 49 and the address generation circuits 47, 48 are controlled by the CPU 11 of the data recording / reproducing apparatus 10. In this Figure 3, CP
The control signal from U11 is indicated by CTL, the write address from the write address generating circuit 47 is indicated by ADR_W, the read address from the read address generating circuit 48 is indicated by ADR_R, and the output from the output terminal a of the selector 49 of the crossbar switch is indicated. The address output is indicated by ADR_a, and the address output from the output terminal b is indicated by ADR_b.

The operation of the buffer memory having such a double buffer structure will be described. Here, prior to the description of the buffering according to the embodiment of the present invention, the operation in the case where it is assumed that writing and reading to and from the buffer memory are performed continuously at the same transfer rate 4 will be described with reference to FIG.

In the example of FIG. 4, the sizes of the buffers 41 and 42 are represented by real time conversion, that is, reproduction time when used for reproduction at a constant rate, and both are set to T0.
Time t = when the file F1 of the predetermined audio / video signal is being reproduced
At t0, when the remaining data size of the file F1 on the reading side, that is, the buffer 42 side in FIG. 4 is T1, and another PLAY command (playback command) of a new predetermined audio / video signal file F2 is received. explain.

FIG. 4A shows the state of each of the buffers 41 and 42 at the time t = t0. In the buffer 41, the unreproduced data of the file F1 exists by the size T1. Also,
Data of the file F1 of size T0-T1 has already been written in the buffer 42. At this time, the data of the file F2 starts to be written in the buffer 41.

FIG. 4B shows the states of the buffers 41 and 42 at time t = t1 after a short time has elapsed from the time t0, and the file F1 is continuously read from the buffer 42. File F2 is written in the buffer 41.

FIG. 4C shows time t = t2 after the time of the size T1 of the unreproduced data has elapsed from the time t0.
Shows the state of each buffer 41, 42 at (= t0 + T1),
The buffer 42 becomes empty and the buffer 41 becomes full. Immediately after this, as shown in FIG. 4D, the read (write) and write (write) buffers are exchanged, and the data of the file F1 is read from the buffer 41.

FIG. 4E shows the state of the buffers 41 and 42 at time t = t3 after a short time has elapsed from the time t2. The file F1 is read from the buffer 41 and The file F2 is written in 42.

FIG. 4F shows time t = t4 (= time after the time of the size T0 of the buffer elapses from the time t0.
t0 + T0), the state of each buffer 41, 42 is shown, and the file F2 starts to be read from the buffer 41,
The file F2 is written in the buffer 42. That is, upon receiving the PLAY command, reproduction is started after a fixed delay time T0 corresponding to the buffer size has elapsed.

However, in reality, the write rate to the buffer memory and the read rate are different, and the buffer memory is provided to absorb the difference between these rates. That is, when data is reproduced by the audio / video data recording / reproducing device 10 using a disk device such as an HDD in the data storage device 30 of FIG. 1, the data from the disk device is necessary for reproducing the audio / video data. The data is faster than the transfer rate but discontinuous. On the other hand, a constant transfer rate is required to output audio / video data. Therefore, the buffer memory 3 is provided between the data storage device 30 and the audio / video signal I / F circuit 34.
2 is needed. It is necessary to write the data from the data storage device 30 to the buffer memory 32 and read the buffer memory to reproduce the audio / video data at the same time. Therefore, it consists of a double buffer and dual port memory (Dual Port Memory). When reproducing audio / video data, the buffer memory is controlled like a FIFO.

By the way, the insertion of the tape in the above-mentioned conventional VTR system corresponds to the OPEN of the file in the audio / video data recording / reproducing apparatus using the disk device. The above C of the next audio / video data as performed by the VTR
UEUP is not possible with one buffer memory. P without opening CUEUP for the opened file
When LAY is executed, if writing to and reading from the buffer memory are continuous at the completely same transfer rate, it is possible to reproduce with fixed delay after receiving PLAY, but transfer for reading data from the disk device. The rate (that is, the transfer rate for writing to the buffer) is different from the transfer rate for reading from the buffer, and it is discontinuous.
There is no fixed delay from the time the command is received until the audio / video signal is played back.

This point will be described with reference to FIG. The example of FIG. 5 shows a case where the transfer rate for writing to the buffer memory is faster than the transfer rate for reading from the buffer memory and is discontinuous, and the sizes of the buffers 41 and 42 are set in real time as in the case of FIG. Converted to T0
When the audio / video signal file F1 is being reproduced, the remaining data size of the file F1 on the reading side buffer 42 side is T1.
At time t = t0, P of audio / video signal file F2
It is assumed that the LAY command has been received.

FIG. 5A shows the state of each of the buffers 41 and 42 at the time t = t0. In the buffer 41, the unreproduced data of the file F1 exists by the size T1. Also,
The data of the file F1 of size T0- (T1-ΔT) has already been written in the buffer 42. This ΔT is a value that differs depending on the data supply state from the data storage device 30 and is not a fixed value. At this time, P of the above file F2
In response to the LAY command, the file F2 is stored in the buffer 41.
Data will start to be written.

FIG. 5B shows the state of each of the buffers 41 and 42 at time t = t1 after a short time has passed from the time t0, and the file F1 is continuously read from the buffer 42. The file F2 is written in the buffer 41.

FIG. 5C shows time t = t2 after the time of the size T1 of the unreproduced data has elapsed from the time t0.
Shows the state of each buffer 41, 42 at (= t0 + T1),
The buffer 42 is empty and the buffer 41 is full. Immediately after this, the read and write buffers are exchanged, and the data of the file F1 is read from the buffer 41.

FIG. 5D shows the state of each of the buffers 41 and 42 at time t = t3 after a short time has elapsed from the time t2. The file F1 is read from the buffer 41 and The file F2 is written in 42.

FIG. 5E shows time t = t4 (= time after the time of the size T0 of the buffer elapses from the time t0.
t0 + T0) of each of the buffers 41 and 42, and the buffer 41 stores files of the above size ΔT.
Since F1 remains, the file F1 is continuously read from the buffer 41. The file F2 is written in the buffer 42.

FIG. 5F shows T0 + from the time t0.
Time t = t5 (= t0 + T0 + ΔT) after elapse of ΔT time
The state of each of the buffers 41 and 42 in FIG. 4 is shown. The file F2 starts to be read from the buffer 41, and the file F2 is written in the buffer 42.

Therefore, the time from the reception of the PLAY command to the start of reproduction varies by the difference of ΔT and does not become a fixed delay. Thus, PL
Since the reproduction cannot be started with a fixed delay after receiving the AY command, continuous reproduction control of a plurality of audiovisual files using the automatic driving device is impossible.

If a structure for realizing CUEUP in the case of the conventional VTR is adopted, reproduction can be started with a fixed delay, but for that purpose, a buffer memory for CUEUP is required in addition to the buffer memory used for reproduction. . CU
Since the buffer memory for EUP is hardly read or written, the usage efficiency is very low. That is, almost useless memory is needed only for CUEUP.

Therefore, in the embodiment of the present invention, the read / write control of the buffer memory 32 is devised so that the reproduction is started with a fixed delay time after the reproduction command (PLAY command) is issued.

The buffering operation by the buffer memory 32 in this embodiment of the present invention will be described with reference to FIGS. 6, 7 and 8. 6 and 7
For each of the buffers 41, 42, as in FIG.
Of the audio / video signal at the time t = t0 when the remaining data size of the file F1 of the buffer 42 on the reading side is T1 during reproduction of the audio / video signal file F1. It is assumed that the PLAY command, which is a reproduction instruction of the file F2 of FIG. FIG. 8 is a flowchart for explaining the buffering operation.

First, as shown in step ST101 of FIG. 8, the file F1 is reproduced from the buffer 42.

FIG. 6A shows the state of the buffers 41 and 42 at the time t = t0. In the buffer 41, the unreproduced data of the file F1 exists for the size T1. In addition, the file F1 of size T0- (T1-ΔT) is stored in the buffer 42.
Data has already been written. This ΔT is a value that differs depending on the data supply state from the data storage device 30 and is not a fixed value. At this time, the write address ADR_W of the buffer 41 indicates T0-T1 + ΔT, and the buffer 42
Read address ADR_R points to T0-T1. In this state, as shown in step ST102 of FIG. 8, the reproduction command (PLAY command) of the file F2 is received.

FIG. 6B shows the state of each of the buffers 41 and 42 immediately after receiving the PLAY command of the file F2 at the time t = t0, and the write address ADR_W of the buffer 41 is T0. -T1 + ΔT is changed to T0-T1 (step ST103 in FIG. 8), and the data of the file F2 starts to be written from this address T0-T1.

FIG. 6C shows the states of the buffers 41 and 42 at time t = t1 after a short time has elapsed from the time t0. As shown in step ST104 of FIG. The data of the read address ADR_R of the file F1 is read, and the data of the file F2 is written to the write address ADR_W of the buffer 41.

FIG. 6D shows time t = t2 after the time of the size T1 of the unreproduced data has elapsed from the time t0.
Shows the state of each buffer 41, 42 at (= t0 + T1),
As shown in step ST105 of FIG.
The read address ADR_R reaches the end T0 and is empty.
Then, the buffer 41 is full (FULL) when the write address ADR_W reaches the end T0. Immediately after this,
As shown in FIG. 8A, the read and write buffers are exchanged (step ST10 in FIG. 8).
6), the read address ADR_R of the buffer 41 and the write address ADR_W of the buffer 42 are both at the start address 0
Becomes Therefore, the data of the file F1 is read from the starting end address 0 of the buffer 41, and the data of the file F2 is written from the starting end address 0 of the buffer 42.

FIG. 7B shows the state of each of the buffers 41 and 42 at time t = t3 after a short time has elapsed from the time t2, and as shown in step ST107 of FIG. File F1 is read from and buffer 4
File F2 is written in 2.

FIG. 7C shows time t = t4 (= time after the time of the size T0 of the buffer elapses from the time t0.
t0 + T0), the read address ADR_R of the buffer 41 is T0-T1, and the file F2 previously written after this address T0-T1 begins to be read. The file F2 is written in the buffer 42. This corresponds to the reproduction of the file F2 from the buffer 41 shown in step ST108 of FIG.

Therefore, in response to the PLAY command,
The reproduction is started after the fixed delay time T0 corresponding to the buffer size has elapsed. That is, it is possible to start the reproduction with the fixed delay time T0 from the time of receiving the PLAY command of the reproduction start signal by using the buffer memory only for the reproduction. In addition, a memory dedicated to CUEUP, which is used for reading and writing and is low in efficiency, becomes unnecessary.

[0062]

As described above, according to the present invention,
A buffer memory having two buffers is provided between a data recording / reproducing means for recording a video and / or audio data file in a randomly accessible recording medium and reproducing the recorded data file, and an external input / output terminal. , The write address of the buffer being written in the buffer memory is controlled to be changed to the write start position for newly writing the data amount equal to the data amount of the buffer being read according to the file playback command. The audio / video data of the file is read out from the buffer memory and output after a fixed delay time corresponding to the buffer size has elapsed after the file reproduction command of the new audio / video data file is given.

That is, it is possible to start reproduction with a fixed delay time after receiving a reproduction start command using a buffer memory only for reproduction, without using a memory for exclusive use of CUEUP having low usage efficiency. Reproduction control similar to that of so-called CUEUP in an automatic driving control system using a VTR can be performed, and continuous reproduction control of a plurality of audio / video files can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a data recording / reproducing apparatus to which an embodiment of the present invention is applied.

FIG. 2 is a block diagram showing a data flow during recording and reproduction in the data recording / reproducing apparatus shown in FIG.

FIG. 3 is a diagram showing a specific example of a configuration of a buffer memory in the data recording / reproducing apparatus shown in FIG.

FIG. 4 is a diagram for explaining an example of buffer memory control during data reproduction.

FIG. 5 is a diagram for explaining another example of buffer memory control during data reproduction.

FIG. 6 is a diagram for describing an example of buffer memory control during data reproduction according to the embodiment of the present invention.

FIG. 7 is a diagram for explaining an example of buffer memory control during data reproduction according to the embodiment of the present invention.

FIG. 8 is a flowchart for explaining an example of buffer memory control during data reproduction according to the embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration example of an audio / video signal continuous reproduction system using a VTR.

FIG. 10 is a timing chart showing an example of audio / video signal continuous reproduction control using a VTR.

FIG. 11 is a flowchart for explaining the operation of an example of audio / video signal continuous reproduction control using a VTR.

FIG. 12 is a flowchart for explaining the operation of an example of audio / video signal continuous reproduction control using a VTR.

[Explanation of Codes] 10 Data Recording / Reproducing Device, 11 CPU, 14
Control signal I / F circuit, 15 file management information storage unit,
20 automatic operation control device, 30 data storage device,
31 data storage I / F circuit, 32 buffer memory, 33 encoder / decoder, 34 video / audio signal I / F circuit, 35 external input / output terminal, 41, 42
Buffer, 44, 45, 49 selector, 47
Write address generation circuit, 48 read address generation circuit

Claims (3)

[Claims] 1. A data recording / reproducing means for recording a video and / or audio data file on a randomly accessible recording medium and reproducing the recorded data file; and a data recording / reproducing means and an external input / output terminal. A buffer memory provided between the two buffers, address generating means corresponding to the respective buffers, and selecting means for switching and selecting one of the two buffers for writing and the other for reading; Control means for controlling the address generating means and the selecting means for changing the write address of the buffer being written in the buffer memory to an address equal to the read address of the buffer being read in response to the file reproduction command. A data recording and / or reproducing apparatus comprising: 2. The control means switches the video and / or audio data file to be reproduced from the data recording / reproducing means from the first file to the second file in response to the file reproducing command, and stores it in the buffer memory. The data recording and / or reproducing apparatus according to claim 1, which is sent. 3. A data recording and / or reproducing method for recording and / or reproducing a video and / or audio data file to / from a data recording / reproducing means having a randomly accessible recording medium via a buffer memory. In response to an input of a file reproduction command for switching and reproducing from the first file which is currently being reproduced among the video and / or audio data files recorded in the data recording / reproducing means to a new second file. A data recording and / or reproducing method, characterized in that the write address of the buffer being written in the buffer memory is controlled to be changed to an address equal to the read address of the buffer being read.