JP2001086430A - Recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable special reproducing without reducing recording capacity. SOLUTION: A bit rate data generating circuit 15 generates the bit rate of a recording service from the number of packets during a recording period and holds the generated bit stream in a bit rate data recording part 19 while relating it to the recording stream of a stream recording part 12. At the time of special reproducing, a file pointer control circuit 17 finds a reading position on the basis of the bit rate and designates it to the stream recording part 12. Thus, jump reproducing and fast forward reproducing or the like can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus capable of performing special reproduction of a recorded stream.

[0002]

2. Description of the Related Art In recent years, MPEG (Moving Picture Exper
With the establishment of high-efficiency coding techniques such as ts Group 2), digitization of images is progressing, and recording devices for digital video signals and audio signals are also being digitized.

In MPEG2, PS (Progr)
am Stream) and TS (Transport S)
stream) are defined. In particular, the TS system has a function of coping with transmission errors and multiplexing and transmitting a plurality of programs, and supports multi-channel broadcasting and multi-media communication or storage media.

In the TS system, transmission data is transmitted in fixed-length packet units in order to facilitate time-division multiplexing of a plurality of images, sounds, data, and the like.
The recording device records the entire transport stream or only a part of the packets corresponding to the service selected from the transport stream. At the time of reproduction, reproduction is performed by depacketizing and decoding the transport stream.

When reproducing a recorded stream,
In addition to the normal reproduction in which the stream is sequentially read from the beginning of the file and reproduced, there are a method of reading and reproducing the stream from a designated time position (hereinafter, referred to as jump reproduction) and a method of performing fast forward reproduction.

[0006] Jump playback is generally a method in which a user designates a position at which playback is to be started by time. For example, 1
If the user wants to start playback from 0 minutes later, the user must enter “10
After a minute "to the recording / reproducing apparatus. The recording / reproducing apparatus searches for a position (address) of the file corresponding to 10 minutes after the current reproduction position, and starts reproduction from that position.

[0007] Fast forward reproduction is a method of reproducing at a speed higher than a normal reproduction speed. That is, data is read from the stream file while skipping data at appropriate frame intervals, and only the read frame data is decoded and reproduced.

By the way, the MPEG2 standard employs variable length coding, and the code amount of each frame is different from each other. Therefore, the capacity required to store data for one screen differs for each screen, and the time required for reading also differs for each screen. For this reason, the change in the time instructed by the user for jump reproduction and the change in the recording address of the stream are not fixed, and it is difficult to find the file position corresponding to the time specified by the user. Similarly, it is also difficult to determine the recording position of a frame for fast-forward playback.

Therefore, there is a method of recording information indicating the relationship between the recording position (address) of the stream file to be recorded and the reproduction time in a table (hereinafter referred to as a random access table) at the time of recording. In the case of jump reproduction, jump reproduction is enabled by referring to the random access table, obtaining the address of the recording file associated with the designated time, and reading the file from the obtained address. Similarly,
Also in the case of fast-forward reproduction, by controlling the address of a file recorded in units of frames with reference to the random access table, data can be read out while thinning out in units of frames.

The random access table is usually stored in a recording device as a file associated with a stream file. At the time of jump reproduction and fast forward reproduction, the random access table is read from the recording device to control the read address of the stream file.

However, since the random access table is a table in which the reproduction time and the address are sequentially associated, the file size increases in proportion to the recording time, and the longer the recording time, the smaller the recording capacity of the recording device. There was a problem of pressure.

[0012]

As described above, conventionally, when performing special reproduction such as jump reproduction and fast-forward reproduction, a random access table is required, and the recording capacity of the recording apparatus is reduced. There was a point.

The present invention has been made in view of such a problem, and enables a jump reproduction and a fast-forward reproduction without using a random access table, thereby reducing a required recording capacity. An object of the present invention is to provide a recording and reproducing device.

[0014]

A recording / reproducing apparatus according to the present invention comprises: recording means for recording a stream encoded with high efficiency; bit rate acquiring means for acquiring a bit rate of the stream; Special playback control means for designating the playback position of the stream recorded by the recording means based on the bit rate acquired by the bit rate acquisition means.

[0015] In the present invention, the stream that has been encoded with high efficiency is recorded by the recording means. The bit rate obtaining means obtains the bit rate of the recorded stream. The trick play means designates the playback position of the stream recorded by the recording means based on the bit rate acquired by the bit rate acquisition means during trick play.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the recording / reproducing apparatus according to the present invention.

According to the present embodiment, when recording a transport stream, the bit rate of the transport stream is calculated for each recording service (program of a channel), and the bit rate is recorded in association with the transport stream. By reading the recorded bit rate and controlling the read address, special reproduction such as jump reproduction and fast forward reproduction can be performed.

A transport stream is input to an input terminal 1. This transport stream may be, for example, a signal obtained by demodulating a received digital broadcast signal, or may be a reproduced signal of a transport stream recorded in another recording device.

The transport stream input via the input terminal 1 is supplied to the selector 2. Selector 2
Is also supplied with a transport stream from the stream recording unit 12. The stream recording unit 12 holds a transport stream from the gate 11 described later as a file.

The selector 2 is controlled by the recording control circuit 4 to select one of the input stream 1 and the transport stream from the stream recording section 12 and output it to the TS demultiplexer 5. The TS demultiplexer 5 depackets the input transport stream, extracts desired video signals and audio signals, and outputs the extracted signals to the MPEG decoder 6. The MPEG decoder 6 decodes the depacketed stream and outputs a video signal and an audio signal to the display device 7. The display device 7 projects an image based on the input video signal and audio signal, and outputs sound from a speaker (not shown).

On the other hand, the output of the selector 2 is also supplied to a video PID filtering circuit 8, an audio PID filtering circuit 9, a PCR_PID filtering circuit 10, and a recording control circuit 4 in order to record a desired service in the transport stream. You. The user can specify which service in the transport stream is to be recorded.

By a user operation of an operation unit (not shown), a command for designating a service ID of a service desired to be recorded by the user and for starting and stopping recording is input to the terminal 3. The information input to the terminal 3 is supplied to the recording control circuit 4.

When performing recording, the recording control circuit 4
By controlling the selector 2, the transport stream from the input terminal 1 is selected. The transport stream includes SI (Servic), which is information related to the entire broadcast service.
e lnformation) are multiplexed, and SI is, for example,
SDT (Service Defini
and an EIT (Event Information Table) that describes detailed information of programs in the service.
Further, a PCR (Program Clock Reference) serving as a time reference of the stream is also inserted into the transport stream. Each of these packets has a PID for identifying the packet.

The recording control circuit 4 extracts the SI included in the transport stream from the selector 2, compares the service ID list described in the SI with the service specified by the user, , The PID is obtained for the video signal, audio signal and PCR included in the service. The recording control circuit 4 includes a video signal,
The PID of each packet of the audio signal and the PCR
The ID filtering circuit 8, audio PID filtering circuit 9, and PCR_PID filtering circuit 10 are set. Further, at the time of recording, the recording control circuit 4 outputs a recording period signal indicating that recording is being performed to the gate 11, the packet counter 14, and the packet number measurement time generation circuit 16.

The video PID filtering circuit 8 extracts a packet corresponding to the PID value of the video signal set by the recording control circuit 4 from the input transport stream, and outputs the packet to the gate 11. Also,
The audio PID filtering circuit 9 extracts a packet that matches the PID value of the audio signal set by the recording control circuit 4 from the input transport stream, and outputs the packet to the gate 11. In addition, PCR_
The PID filtering circuit 10 extracts a packet matching the PID value of the PCR set by the recording control circuit 4 from the input transport stream, and outputs the extracted packet to the gate 11.

The gate 11 is controlled by the recording control circuit 4 to output the input packet to the stream recording unit 12. When the recording period signal from the recording control circuit 4 indicates that recording is being performed, the gate 11
The input transport stream is stored in the stream recording unit 12 as a file.

The video PID filtering circuit 8, the audio PID filtering circuit 9, and the PCR
The _PID filtering circuit 10 outputs a detection signal indicating that a packet matching the PID set by the recording control circuit 4 is detected to the OR circuit 13. The OR circuit 13 takes the logical sum of the three input detection signals and outputs the result to the packet counter 14.

The packet counter 14 is provided by the OR circuit 13
The output of is counted. The output of the OR circuit 13 indicates the insertion position of each packet of the video signal, the audio signal, and the PCR included in the service designated by the user, and the packet counter 14 outputs the output of the OR circuit 13 according to the recording period signal. Is counted to obtain the number of packets of the stream to be recorded.

In this embodiment, the output of the packet counter 14 is supplied to a bit rate data generation circuit 15. The output of the packet counter 14 indicates the number of packets corresponding to the service specified by the user existing in the transport stream after the start of recording. On the other hand, a recording period signal indicating whether or not recording is being performed is input from the recording control circuit 4 to the packet number measurement time generation circuit 16. The packet number measurement time generation circuit 16
A recording period signal is provided, and information indicating a measurement time for counting the number of packets during the recording period is output to the bit rate data generation circuit 15.

The bit rate data generation circuit 15 generates a measurement period signal indicating a period for measuring the number of packets based on the information indicating the measurement time from the packet number measurement time generation circuit 16, and generates a signal period (measurement period). During the period, the number of packets output from the packet counter 14 is calculated. That is, the bit rate data generation circuit 15 obtains the number of packets corresponding to the service specified by the user existing in the transport stream during the measurement period after the start of recording. Further, the bit rate data generation circuit 15 obtains the bit rate of the recording service from the obtained number of packets by the following equation (1). It is assumed that the transport stream has a fixed packet length of 188 bytes.

Bit rate [bps] = number of packets × 188 × 8 [bit] / measurement period [second] (1) The bit rate data generation circuit 15 streams information of the bit rate obtained by the above equation (1). Recording unit 12
The file is stored in the bit rate data recording unit 19 in association with the stream file recorded in the. The bit rate information recording section 19 records bit rate information for each service recorded in the stream recording section 12.

At the time of reproduction, the selector 2 selects and outputs the output of the stream recording unit 12. In the present embodiment, reading of the stream recording unit 12 is controlled by the file pointer control circuit 17. Information based on a user operation is input to the file pointer control circuit 17 via the terminal 18. For example, from the terminal 18, information such as the time in jump playback and the number of double speeds in fast-forward playback is input. The file pointer control circuit 17 reads the bit rate data associated with the service specified by the user from the bit rate data recording unit 19, and converts the input information into a read address value based on the read bit rate. .

For example, when time information for jump reproduction is input, the file pointer control circuit 17
Calculates the read address by the following equation (2).

Read address [Byte] = Bit rate × 8 [Byte] × Time information [Second] (2) For example, when the file pointer control circuit 17 performs fast-forward playback by playing back only I pictures. , The read address is calculated by the following equation (3).

Read address [Byte] = Bit rate × 8 [Byte] × I picture insertion interval [Second] (3) The file pointer control circuit 17 reads out the stream recording unit 12 using the obtained read address. Control.

Next, the operation of the embodiment configured as described above will be described with reference to FIGS. FIG. 2 is a timing chart for explaining the operation of the embodiment. FIG. 2A shows the recording control circuit 4 to the gate 11,
2 shows signals output to the packet counter 14 and the packet number measurement time generation circuit 16. FIG. 2B shows the output of the selector 2. In FIG. 2, one packet is represented by one rectangle, and the PID is represented by English characters in the rectangle. In FIG. 2, [V]
Indicates the PID of any one video signal included in the service selected by the user, [A] indicates the PID of any one audio signal included in the service selected by the user, and [P] indicates the PID of the user. P included in the selected service
The PID of the CR is shown. Further, (VI) indicates a packet including the head of an I picture in the PID of any one video signal included in the service selected by the user. Note that an I picture is a video signal that has been intra-frame coded or intra-field coded. [X] in FIG. 2 indicates a packet other than the service selected by the user. FIG. 2C shows a transport stream output from the video PID filtering circuit 8, and FIG. 2D shows a transport stream output from the audio PID filtering circuit 9.
FIG. 2E shows a transport stream output from the PCR_PID filtering circuit 10.
FIG. 2F shows a transport stream input to the gate 11, and FIG. 2G shows a transport stream output from the gate 11. FIG. 2 (h)
2 shows the output of the OR circuit 13, FIG. 2 (i) shows the output of the packet counter 14, and FIG. 2 (j) shows the output of the packet number measurement time generation circuit 16.

Now, it is assumed that the selector 2 selects and outputs the transport stream from the input terminal 1. The transport stream shown in FIG. 2B is transmitted from the selector 2 to the TS demultiplexer 5 and the video PID.
The signals are output to the filtering circuit 8, the audio PID filtering circuit 9, and the PCR_PID filtering circuit 10.

The TS demultiplexer 5 selects a packet of the program desired by the user from the input transport stream and supplies the selected packet to the MPEG decoder 6.
The G decoder 6 decodes the input packet. Thus, the video signal and the audio signal of the program corresponding to the user's channel selection operation are output from the MPEG decoder 6 and supplied to the display device 7. The display device 7 displays the video of the program selected by the user and outputs sound.

Here, it is assumed that the user records a broadcast signal. A signal based on a user operation is supplied from a terminal 3 to a recording control circuit 4. Then, the recording control circuit 4 outputs a recording period signal indicating that recording is being performed as shown in FIG. 2A to the gate 11, the packet counter 14, and the packet number measurement time generation circuit 16 at timing T1. In addition,
The recording period signal shown in FIG.
“H”) indicates that recording is in progress.

The recording control circuit 4 converts the video signal, audio signal, and PID of each packet of the PCR of the program selected by the user into a video PID filtering circuit 8, an audio PID filtering circuit 9, and a PCR_PI
This is set in the D filtering circuit 10.

As a result, the video PID filtering circuit 8 extracts the video packet shown in the frame of FIG.
Output to 1. Further, the video PID filtering circuit 8 outputs a signal indicating that the video packet has been extracted at the extraction timing of the video packet to the OR circuit 13.

Similarly, the audio PID filtering circuit 9 extracts a video packet and outputs a signal to the OR circuit 13 at the extraction timing as shown in FIG. 2D, and the PCR_PID filtering circuit 10
As shown in FIG. 2E, a PCR packet is extracted, and a signal is output to the OR circuit 13 at the extraction timing.

FIG. 2F shows a packet input to the gate 11. When the recording period signal from the recording control circuit 4 becomes “H”, the gate 11 transfers the packet from the video PID filtering circuit 8, the audio PID filtering circuit 9 and the PCR_PID filtering circuit 10 as shown in FIG. Stream recording unit 1
Output to 2. Thus, only the packets of the program desired by the user are recorded in the stream recording unit 12.

On the other hand, the logical sum circuit 13 calculates the logical sum of the input signals and outputs the signal shown in FIG. The packet counter 14 counts the output of the OR circuit 13 during recording. The numbers in FIG. 2 (i) indicate count values. The count value of the packet counter 14 indicates the number of packets in the transport stream corresponding to the service specified by the user after the start of recording. The count value is supplied to the bit rate data generation circuit 15.

On the other hand, the packet number measurement time generation circuit 16
Sets the time for measuring the bit rate of the service being recorded. That is, the packet number measurement time generation circuit 1
6 outputs a signal indicating the measurement time to the bit rate data generation circuit 15. Bit rate data generation circuit 15
Generates a measurement period signal (FIG. 2 (j)) that becomes “H” for a time corresponding to the measurement time Tm based on the measurement time information input from the packet number measurement time generation circuit 16.
The measurement period signal indicates the measurement period by “H”.

The bit rate data generation circuit 15 calculates the number of packets during the measurement period using the number of packets input from the packet counter 14 during the “H” period of the measurement period signal. In the example of FIG. 2, the measurement period is between the timings T2 and T3 in FIG. 2, and the number of packets at the timing T2 is "3" and the number of packets at the timing T3 is "15".
Determines that the number of packets during the measurement period is “12”. This value indicates the number of packets during the measurement period corresponding to the service specified by the user.

The bit rate data generation circuit 15 obtains the bit rate of the service being recorded by, for example, the above equation (1). The bit rate data generation circuit 15
The determined bit rate data is associated with the packet data to be recorded in the stream recording unit 12 and recorded in the bit rate data recording unit 19.

Here, the user inputs the stream recording unit 12
In this case, it is instructed to perform jump playback of the stream recorded in the. The recording control circuit 4 causes the selector 2 to select the output of the stream recording unit 12. In addition, the user specifies a jump position by time. The jump time information is transmitted to the file pointer control circuit 1 via the terminal 18.
7 is supplied.

On the other hand, the file pointer control circuit 17
The bit rate data associated with the service designated to be reproduced is read from the bit rate data recording unit 19, and the time information is converted into a read address value of the stream recording unit 12 using the read bit rate. In this case, for example, the calculation method of the above equation (2) is used.

The value of the read address in the above equation (2) is the position of the file where the reproduction is started after the jump. The file pointer control circuit 17 specifies the obtained read address value to the stream recording unit 12. As a result, the stream file is read from the position where the user jumps for the time designated by the user, and is supplied to the selector 2.
Thus, jump reproduction is performed.

Next, the operation at the time of fast forward reproduction will be described with reference to FIG. FIG. 3 is a flowchart showing an operation flow during fast forward reproduction.

Now, it is assumed that the user performs a fast forward operation during normal reproduction. The command based on the fast forward operation is sent to terminal 18
Is supplied to the file pointer control circuit 17 to start the fast forward reproduction in step S1. The file pointer control circuit 17 reads out bit rate data associated with the stream file being reproduced from the bit rate data recording unit 19.

The file pointer control circuit 17 sequentially advances the read address of the stream recording unit 12 until an I picture is detected in step S2. The stream from the stream recording unit 12 is supplied to the TS demultiplexer 5 via the selector 2 and further supplied to the MPEG decoder 6 for decoding. The I-picture is detected by the MPEG decoder 6. MPEG
When detecting the I picture, the decoder 6 notifies the file pointer control circuit 17 of the detection of the I picture.

After the detection of the I picture is notified, the file pointer control circuit 17 performs reading by sequentially advancing the read address by the maximum size of the I picture (step S3). As a result, data of one I-picture portion is read from the stream recording unit 12. The data of the I picture is decoded by the MPEG decoder 6,
An image based on the decoded I picture is displayed on the display device 7.

The file pointer control circuit 17 has an MPE
Data indicating the GOP (Group 0 Picture) structure is also given from the G decoder 6, and the file pointer control circuit 17 sends the bit rate data read from the bit rate data recording unit 19 and the GOP from the MPEG decoder 6.
With reference to the data of the structure, the insertion position of the next I picture is obtained.

That is, the file pointer control circuit 17
By analyzing the GOP structure, the insertion interval of the I picture is grasped, and the read address is obtained based on the above equation (3). In the next step S4, the file pointer control circuit 17 advances the read address slightly less than the address obtained by the above equation (3). As a result, a read address is set before the next I picture in the stream recording unit 12, and the stream file is reproduced.

The read address value in the above equation (3) is based on the average bit rate during the measurement period, and is not always the head of the I picture. Therefore, by setting the read address slightly before the obtained address, it is possible to reliably reproduce the head of the I picture.

Next, the file pointer control circuit 17
Returns the process to step S2, and sequentially advances the read pointer until the next I picture is detected. MPEG
The decoder 6 is reliably supplied with the data of the I picture and decodes the I picture. Since data is sequentially input to the MPEG decoder 6 from the data before the I picture, it is necessary to control the MPEG decoder 6 so as not to decode pictures other than the I picture during fast forward reproduction.

Thereafter, the same operation is repeated, and the MPEG decoder 6 performs decoding for each I picture, and the display device 7 displays an image using only the I picture. Thereby, fast forward reproduction is realized.

As described above, in the present embodiment, when recording a transport stream, information on the bit rate of the transport stream is recorded for each service,
During jump playback or fast-forward playback, transport stream read control is performed based on the recorded bit rate information. As a result, special reproduction such as jump reproduction and fast-forward reproduction can be performed using only a very small amount of bit rate data without using a random access table whose file size increases in proportion to the recording time.

FIG. 4 is a block diagram showing another embodiment of the present invention. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In the embodiment of FIG. 1, the bit rate is obtained only once at the time of recording. However, in the present embodiment, the bit rate is calculated a plurality of times at an appropriate timing in order to cope with a change in the bit rate. The result is stored as a file.

This embodiment differs from the embodiment of FIG. 1 in that an address generation circuit 21 and a bit rate data table generation circuit 22 are added. Address generation circuit 21
Is the timing at which the packet counter 1 receives the measurement time information output from the packet number measurement time generation circuit 16.
After latching the output value of No. 4 and converting it to an address value, the output value is output to the bit rate data table generation circuit 22. The value latched by the address generation circuit 21 indicates the number of recording service packets at the moment of recording, and the address value can be calculated from the number of packets.

Bit rate data table generation circuit 22
Also receives the output of the bit rate data generation circuit 15. The bit rate data table generation circuit 22 associates the bit rate data output from the bit rate data generation circuit 15 with the address value output from the address generation circuit 21, and stores the bit rate data in the bit rate data recording section 19.
Is saved as a bit rate data file. The bit rate data file has a description including the bit rate and the timing at which the bit rate is determined so that the bit rate has changed.

Next, the operation of the embodiment configured as described above will be described with reference to the explanatory diagram of FIG. 5, and FIGS. 6 and 7. 5 (a) to 5 (e) show operation timings, and FIGS. 5 (f) to 5 (h) show timings T3, T5, T
7 shows the contents of the bit rate data table.

The present embodiment differs from the embodiment of FIG. 1 in that the bit rate is calculated a plurality of times during recording.

Now, it is assumed that a recording start command is given to the recording control circuit 4 via the terminal 3. Then, as shown in FIG. 5A, the recording control circuit 4 sets the recording period signal indicating that recording is being performed to “H”. In the “H” period of the recording period signal, the packet number measurement time generation circuit 16 outputs measurement time information for counting the number of packets to the bit rate data generation circuit 15.

In this embodiment, the measurement time information is output a plurality of times at appropriate timing. For example, it is assumed that the measurement time information is output to the bit rate data generation circuit 15 and the address generation circuit 21 at timings T2, T4, and T6 in FIG.

On the other hand, the output value of the packet counter 14 is
As in the embodiment of FIG. 1, after recording is started, the number of packets corresponding to the service specified by the user existing in the transport stream is shown. The output of the packet counter 14 is the bit rate data generation circuit 1
5 and the address generation circuit 21. The bit rate data generation circuit 15 generates a measurement period signal (FIG. 5B) for measuring the number of packets based on the measurement time information.

For example, the bit rate data generation circuit 15
Are the timings T2, T4, T for receiving the measurement time information.
From 6 on, the measurement period signal is set to “H” for a predetermined period to set the measurement period. Note that the measurement period is a time based on the measurement period information. The bit rate data generation circuit 15 obtains the number of packets during the measurement period, converts the number into a bit rate,
The bit rate data is output to the bit rate data table generation circuit 22 as the bit rate data shown in FIG.

In this embodiment, the measurement time information is also supplied to the address generation circuit 21. The address generation circuit 21 latches the output value of the packet counter 14 at the timing when receiving the measurement time information. That is, the value latched by the address generation circuit 21 indicates the number of packets of the recorded stream at that moment. In the example of FIG.
At each timing of 2, T4 and T6, the packet counter 14
Are latched, and FIG. 5D shows the number of latched packets.

Since the transport stream has a fixed length of 188 bytes, the number of packets can be converted to the number of bytes by multiplying the number of packets by 188. That is, by multiplying the latched value by 188, the size of the stream recorded at the latch timing is indicated. That is, the address generation circuit 21 can obtain the address in the stream recording unit 12 from the latched value. The address generation circuit 21 outputs the obtained address to the bit rate data table generation circuit 22. FIG. 5E shows an output value of the address generation circuit 21.

Bit rate data table generation circuit 22
Generates a table in which the bit rate data output from the bit rate data generation circuit 15 and the address value output from the address generation circuit 21 are associated with each other, and stored in the bit rate data recording unit 19 as a bit rate data table file. save. This table is configured such that immediately after the bit rate data output from the bit rate data generation circuit 15 is updated, the address value output from the address generation circuit 21 is referred to and associated with the updated bit rate data. I do.

FIGS. 5F to 5H show the process of generating this table.

As shown in FIG. 5C, at timing T3
In, the bit rate data is updated to 6 Mbps. Immediately after this, the address value output from the address generation circuit 21 is 7520 bytes as shown in FIG. These information, "6Mbps" and "7520"
The two values of “byte” are associated with each other and stored in the bit rate data recording unit 19 as a table file. FIG. 5F shows the contents of the table file generated at the timing T3.

Thereafter, by the same operation, the table file is updated every time the bit rate data is updated.
At timings T5 and T7 in FIG.
The table file shown in (h) has been generated.

As described above, in this embodiment, it is possible to record a table file in which the bit rate at each moment is associated with the address of the stream recorded at that moment.

Next, the operation at the time of jump reproduction will be described with reference to the explanatory diagram of FIG. FIG. 6A shows the contents of the table file, and FIG. 6B shows the relationship between the reproduction time and the designated address, with the vertical axis indicating the address and the horizontal axis indicating the reproduction time.

The user specifies time information corresponding to the jump position. This time information is input to the file pointer control circuit 17 via the terminal 18. The file pointer control circuit 17 reads a table file associated with the stream file from the bit rate data recording unit 19. The table file describes the relationship between the recording address of the stream file in the stream recording unit 12 and the bit rate at that address, and the file pointer control circuit 17 calculates the recording address of the stream file and the playback time from the read table file. Derive a relationship with

Assume that the table file read by the file pointer control circuit 17 is as shown in FIG. In this table file, addresses and bit rates are associated. For example, in the first line, the instantaneous bit rate of the stream recorded at the position where the address value is “7520” is “6000000”.
bps ”. The file pointer control circuit 17 determines that the bit rate is constant between the addresses described in the table file. That is, in the example of FIG.
The bit rate between “00” and “206800” is “6000000 bps”, and the address is “206800”.
The bit rate between “357200” and “357200” is “59”.
00000 bps ”.

In each section, the relationship between the address and the reproduction time is represented by the following equation (4).

Address [Byte] = Bit Rate [bps] × Reproduction Time [Second] / 8 (4) FIG. 6B is a graph of the relationship of the above equation (4).

The file pointer control circuit 17 derives the relationship between the recording address of the stream file and the reproduction time by the above equation (4). For example, when time information from the terminal 18 is specified on the reproduction time axis in FIG. 6B, the address value is uniquely determined. The file pointer control circuit 17 designates the obtained read address value to the stream recording unit 12 assuming that the read address value thus obtained is the recording position of the file to be reproduced after the jump. As a result, the stream file is read from the position where the user jumps for the time designated by the user, and the jump reproduction is performed.

Next, the operation at the time of fast forward reproduction will be described with reference to the flowchart of FIG.

Also in the present embodiment, fast forward reproduction is realized by reproducing only I pictures. Now, it is assumed that a fast-forward command is input to the file pointer control circuit 17 via the terminal 18 during normal reproduction. Then, the file pointer control circuit 17
Stores the table file associated with the stream file currently being reproduced in the bit rate data recording unit 19.
Read from

The file pointer control circuit 17 sequentially advances the read address until an I picture is detected in step S 2, and data is sequentially read from the stream recording unit 12. The MPEG decoder 6 decodes the input stream, and outputs an I picture detection signal indicating that an I picture has been detected, and a GO picture.
A signal indicating the P structure is output to the file pointer control circuit 17.

When notified of the detection of the I picture, the file pointer control circuit 17 determines in step S3 that the I picture
The read address is sequentially advanced by the maximum size of the picture. As a result, data for one I picture is read from the stream recording unit 12 and decoded by the MPEG decoder 6.

In the present embodiment, the next step S
In step 11, the file pointer control circuit 17 refers to the read table file to determine the bit rate of the read address position after reading the data of one I picture. For example, if the table file is as shown in FIG.
The read address after reading the data of one I picture is “300,00”.
0 ". In this case, "300,00
The value “0” is a value between “206,800” and “357,200” in the bit rate data table, and the bit rate in this section is “206, 800”.
"5,900," associated with the address value of "800"
000 bps ”, the required bit rate is
It is determined to be “5,900,000 bps”.

In the next step S12, the file pointer control circuit 17 determines the bit rate obtained in step S11 and the GOP input from the MPEG decoder 6.
With reference to the data indicating the structure, the insertion position of the next I picture is obtained. The fact that the file pointer control circuit 17 sets a read address slightly smaller than the address obtained in step S12 is the same as in the embodiment of FIG.

The subsequent operation is the same as that of the embodiment shown in FIG. Thus, fast-forward reproduction is realized by decoding and displaying only the I picture.

As described above, in the present embodiment, the bit rate is measured a plurality of times, and the table file that associates the recording stream with the bit rate is recorded.
Reliable addressing is possible even when the bit rate of the stream changes. The number of times the bit rate is measured may be relatively small, and is sufficiently smaller than the capacity of the random access file in the conventional example.

Also, instead of updating the table file every time the bit rate is measured, the table file is updated only when the change in the bit rate exceeds a predetermined threshold, thereby reducing the capacity of the generated table file. Clearly, it can be reduced.

FIG. 8 is a block diagram showing another embodiment of the present invention. 8, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In the embodiment shown in FIG. 1, the bit rate of the transport stream corresponding to the recording service is obtained by measuring the number of packets of the transport stream to be recorded. On the other hand, in the present embodiment, the bit rate of the transport stream corresponding to the recording service is obtained by analyzing the SI multiplexed in the transport stream in advance. The SI includes a table that describes the bit rate of each service, and extracts the bit rate by filtering packets that include this table.

In this embodiment, the OR circuit 13, the packet counter 14, the bit rate data generating circuit 15 and the packet number measuring time generating circuit 16 are deleted, and the bit rate table filtering circuit 31 and the bit rate data extracting circuit 32 are replaced. The added point is different from the embodiment of FIG.

The bit rate table filtering circuit 31 obtains the PID of the SI describing the bit rate of the service from the recording control circuit 4 and sets it in the bit rate table filtering circuit 31. The bit rate table filtering circuit 31 receives the transport stream from the selector 2, extracts a bit rate table, and outputs the extracted bit rate table to the bit rate data extraction circuit 32. The bit rate data extraction circuit 32 extracts bit rate data from the input bit rate table, and records the bit rate data in the bit rate data recording unit 19 in association with the transport stream to be recorded.

In the embodiment configured as described above, as in the embodiment of FIG. 1, the recording control circuit 4 receives the transport stream output from the selector 2 and extracts the SI. The recording control circuit 4 compares the list of service IDs described in the extracted SI with the service specified by the user,
Video signal, audio signal, PC included in the service from
The PID of each packet of SI describing R and the bit rate of the service is obtained. The recording control circuit 4 supplies the PID of the SI packet describing the bit rate of the service to the bit rate table filtering circuit 31.

Thus, the bit rate table filtering circuit 31 takes out the bit rate table from the stream input via the selector 2 and outputs it to the bit rate data extraction circuit 32. The bit rate data extraction circuit 32 extracts bit rate data from the input table and stores the bit rate data in the bit rate data recording unit 19 in association with the recording stream.

The other operations are the same as those of the embodiment shown in FIG.

As described above, in the present embodiment, the bit rate is obtained from the information multiplexed in the transport stream, so that the same effect as that of the embodiment of FIG. The circuit scale can be reduced as compared with the form.

FIG. 9 is a block diagram showing another embodiment of the present invention. In FIG. 9, the same components as those in FIGS. 4 and 8 are denoted by the same reference numerals, and description thereof will be omitted.

In the present embodiment, in order to cope with a change in bit rate, a process of extracting a table file from SI and obtaining bit rate data is performed a plurality of times at an appropriate timing, and is held as a table file. Is shown. Also in this embodiment, similarly to the embodiment of FIG. 4, the bit rate and the timing at which the bit rate is obtained are described in the table file so that the change in the bit rate can be understood. .

This embodiment differs from the embodiment shown in FIG. 4 in that the bit rate table filtering circuit 31 and the bit rate data extracting circuit 32 shown in FIG. 8 are employed as means for obtaining the bit rate.

That is, a bit rate table filtering circuit 31 and a bit rate data extracting circuit 32 are used instead of the OR circuit 13, the packet counter 14, the bit rate data generating circuit 15, and the packet number measuring time generating circuit 16 in FIG. I do. Further, the address generation circuit 21
Is obtained from the bit rate data extraction circuit 32.

In the embodiment configured as described above, the operation of extracting the bit rate by bit rate data extraction circuit 32 is the same as that of the embodiment of FIG. The extracted bit rate data is supplied to the bit rate data table generation circuit 22.

The bit rate data extraction circuit 32
Outputs to the address generation circuit 21 a signal indicating that bit rate information has been extracted from the SI describing the bit rate. The address generation circuit 21 latches the output of the packet counter 14 at the timing of the signal from the bit rate data extraction circuit 32. Address generation circuit 2
1 converts the latched count value into the address of the recording stream and converts the latched count value into the bit rate data table generation circuit 22.
Output to

Bit rate data table generation circuit 22
Associates the bit rate data with the address value and causes the bit rate data recording unit 19 to store the table file. Other operations are the same as those of the embodiment shown in FIGS.

As described above, in the present embodiment, the same effects as those in the embodiments of FIGS. 4 and 8 can be obtained.

Also, instead of updating the table file every time the bit rate is extracted, the table file is updated only when the change in the bit rate exceeds a predetermined threshold, thereby reducing the file capacity. What can be done is the same as the embodiment of FIG.

FIG. 10 is a block diagram showing another embodiment of the present invention. 10, the same components as those of FIG. 1 are denoted by the same reference numerals, and the description will be omitted.

This embodiment is a modification of the embodiment of FIG. 1 in which the bit rate is obtained. In the present embodiment, after recording, a bit rate is obtained based on the file size and the recording time of a recording stream, and the obtained bit rate is stored in association with the recorded stream file.

This embodiment employs a recording time measuring circuit 41 and a bit rate data generating circuit 42 instead of the OR circuit 13, the packet counter 14, the bit rate data generating circuit 15 and the packet number measuring time generating circuit 16. This is different from the embodiment of FIG.

The recording time measuring circuit 41 includes a recording control circuit 4
, A recording period signal is given, and the recording time of the recording service is measured and output to the bit rate data generation circuit 42. The bit rate data generation circuit 42 obtains information on the file size of the recording service from the stream recording unit 12. The bit rate data generation circuit 42 calculates the bit rate from the recording time and the file size for each recording service based on the following equation (5).

Bit rate [bps] = file size [bit] / recording time [second] (5) The bit rate data generation circuit 42 stores the obtained bit rate in the bit rate data recording unit 19 in association with the recording stream. It is made to let.

Next, the operation of the embodiment configured as described above will be described.

This embodiment is different from the embodiment shown in FIG. 1 in the operation of generating bit rate data. The recording control circuit 4 supplies a recording period signal to the gate 11 and the recording time measuring circuit 41. The recording time measuring circuit 41 measures the recording time for each recording service from the input recording period signal. The recording time of each service is supplied to the bit rate data generation circuit 42.

[0117] The bit rate data generation circuit 42 acquires information on the file size of each service from the stream recording unit 12. Then, the bit rate data generation circuit 4
2 calculates a bit rate for each service based on the above equation (5). This bit rate data is stored in the bit rate data recording unit 19 in association with the stream file.

Other functions are the same as those of the embodiment shown in FIG.

As described above, also in the present embodiment, FIG.
The same effect as that of the embodiment can be obtained.

[0120]

As described above, according to the present invention, it is possible to reduce the required recording capacity by enabling jump reproduction and fast-forward reproduction without using a random access table. Have.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a recording / reproducing apparatus according to the present invention.

FIG. 2 is a timing chart for explaining the operation of the embodiment of FIG. 1;

FIG. 3 is a flowchart for explaining the operation of the embodiment of FIG. 1;

FIG. 4 is a block diagram showing another embodiment of the present invention.

FIG. 5 is an explanatory diagram for explaining the operation of the embodiment in FIG. 4;

FIG. 6 is an explanatory diagram for explaining the operation of the embodiment in FIG. 4;

FIG. 7 is a flowchart for explaining the operation of the embodiment of FIG. 4;

FIG. 8 is a block diagram showing another embodiment of the present invention.

FIG. 9 is a block diagram showing another embodiment of the present invention.

FIG. 10 is a block diagram showing another embodiment of the present invention.

[Explanation of symbols]

2 selector 4 recording control circuit 5 TS demultiplexer 6 MPEG encoder 8 video PID filtering circuit 9 audio PID filtering circuit 10 PCR_PID filtering circuit 1
DESCRIPTION OF SYMBOLS 1 ... Gate, 12 ... Stream recording part, 15 ... Bit rate data generation circuit, 16 ... Packet number measurement time generation circuit, 17 ... File pointer control circuit, 19 ... Bit rate data recording part. Attorney Attorney Susumu Ito

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Noriya Sakamoto 8th Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Toshiba Yokohama Office (72) Inventor Atsushi Hirota 8th Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa (72) Inventor Hiroyuki Nagata 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa F-term (reference) 5C052 AA01 AB03 AB04 AC05 BB04 CC06 CC11 DD07

Claims (6)

[Claims] 1. A recording means for recording a stream encoded with high efficiency, a bit rate acquiring means for acquiring a bit rate of the stream, and a bit rate acquired by the bit rate acquiring means during special reproduction. A special reproduction control means for designating a reproduction position of the stream recorded by the recording means. 2. The recording means can record the stream for each service, and the bit rate obtaining means obtains a bit rate based on a data amount per unit time of a stream corresponding to a service to be reproduced. 2. The recording / reproducing apparatus according to claim 1, wherein the stored bit rate is stored in association with the recorded service. 3. The special reproduction means, at the time of fast forward reproduction,
3. The recording / reproducing apparatus according to claim 2, wherein a stream having a size corresponding to a maximum size of a frame to be reproduced is sequentially read, and after the reading, the stream is moved to a next reproducing position based on the stored bit rate. apparatus. 4. The recording / reproducing apparatus according to claim 1, wherein the bit rate obtaining means obtains the bit rate a plurality of times per unit time by obtaining the data amount per unit time a plurality of times. . 5. The recording / reproducing apparatus according to claim 1, wherein the bit rate acquisition unit acquires information indicating a bit rate included in a stream recorded by the recording unit. 6. The recording / reproducing apparatus according to claim 1, wherein the bit rate acquiring unit acquires the bit rate for each service based on a recording time and a recording capacity for each service.