JP2006101093A - Program recording apparatus, program reproducing apparatus and program recording/reproducing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a program recording apparatus which can perform recompression of data or a program even if it is the case where the program reproducing apparatus does not have an encoding function without having a decoding function in a program recording apparatus, and to provide a program reproducing apparatus and a program recording/reproducing system. <P>SOLUTION: A compression controller 21 selects at least one of the data of the program compressed by a compression rate α<SB>0</SB>in a terminal memory 26. A decoder 24 decompresses the data of the selected program in the terminal memory 26. The data of the program decompressed by a transfer unit 15 from a transfer unit 25 is transmitted. An encoder 13 compresses the data of the received program by a compression rate α<SB>1</SB>higher than the compression rate α<SB>0</SB>. The data of the program are transmitted as compressed into the transfer unit 25 by a compression rate α<SB>1</SB>from the transfer unit 15. A recording controller 23 replaces the data of the program compressed by the selected compression rate α<SB>0</SB>in the terminal memory 26 with the data of the program compressed at the received compression rate α<SB>1</SB>. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a program recording apparatus, a program reproducing apparatus, and a program recording / reproducing system, and in particular, compresses and stores received program data, and decompresses the stored program data at the time of reproduction. The present invention relates to an apparatus and a program recording / playback system.

  In recent years, a program recording / reproducing apparatus that compresses and stores program data sent from a broadcast station and decompresses the program data stored at the time of reproduction has been put to practical use.

  In such a broadcast program recording / playback apparatus, for example, Patent Document 1 discloses a method for recompressing received program data stored by compression.

  That is, when the accumulated recording capacity is equal to or greater than a predetermined capacity value, or when a predetermined time (date and time) has elapsed from the recording date and time, it is determined that recompression is possible and recompressible data is stored. Decoded and encoded at a higher compression rate than when it was first recorded.

By such recompression, the accumulated storage capacity can be reduced.
JP 2003-189243 A

  By the way, a mode in which the program recording apparatus and the program playback apparatus operate independently, such as a program recording / playback system including a program recording apparatus installed at home and a portable program playback apparatus, is considered. It is done.

  In such a program recording / playback system, program data is received by a program recording device, compressed by an encoder, and stored. Then, the compressed program data is transferred from the program recording device to the program reproducing device and stored. In the program reproducing apparatus, the program data compressed by the decoder is decompressed and displayed.

  In such a program recording / reproducing system, the program recording apparatus does not have a decoding function, and the program reproducing apparatus does not have an encoding function, so that it is difficult to recompress program data. Further, since the capacity of the storage device of the portable program playback device is limited, there is a high need for recompression of program data stored in the program playback device.

  Therefore, an object of the present invention is to provide a program recording apparatus capable of recompressing program data even when the program recording apparatus does not have a decoding function and the program reproducing apparatus does not have an encoding function, A program reproducing apparatus and a program recording / reproducing system are provided.

  In order to solve the above-described problems, a program recording apparatus of the present invention is a program recording apparatus that does not have a decoding function, a storage unit for storing compressed program data, and a program transmitted from a broadcasting station. A tuner for receiving data; an encoder for compressing the received program data at a first compression rate; a recording control unit for storing the compressed program data in a storage unit; and A communication unit that transfers data, the communication unit receives program data from the program reproduction device that has already been transferred to the program reproduction device and has been decompressed by the first compression ratio, and the encoder The received decompressed program data is compressed at a compression rate higher than the first compression rate, and the recording control unit stores the program data compressed at a compression rate higher than the first compression rate in the storage unit. Save the communication part Transferring data compressed program at a high compression ratio than the first compression ratio in the program playback apparatus.

  Preferably, the program recording device further checks whether there is a free space in the storage unit of the program playback device for storing data of the compressed program to be transferred next time to the program playback device, and there is a free space. If not, a compression control unit is provided for instructing the communication unit to notify the program reproducing apparatus of the volume of compressed program data to be transferred next time.

  Preferably, the communication unit receives, from the program playback device, a compression rate specification for recompressing the program data together with the decompressed program data, and the specified compression rate is higher than the first compression rate. The encoder compresses the received decompressed program data at the designated compression rate, and the communication unit transfers the program data compressed at the designated compression rate to the program reproducing apparatus.

  Preferably, the recording control unit, when receiving from the program playback device the program data that has already been transferred to the program playback device and decompressed the program data compressed at the first compression ratio, The program data compressed at the first compression rate transferred to the apparatus is deleted from the storage unit.

  Preferably, the recording control unit, when receiving from the program playback device the program data that has already been transferred to the program playback device and decompressed the program data compressed at the first compression ratio, The communication unit does not delete the program data compressed at the first compression rate transferred to the apparatus from the storage unit, and the communication unit receives from the program playback device an instruction to select the program data that returns the compression rate to the first compression rate. Then, the program data in which the data of the program instructed to be selected is compressed at the first compression rate is read from the storage unit and transferred to the program reproducing device.

  The program playback device of the present invention is a program playback device that does not have an encoding function, and receives a compressed program data from a storage unit for storing compressed program data and a program recording device. A communication unit, a recording control unit for storing the received compressed program data in the storage unit, and at least one of the program data compressed at the first compression rate in the storage unit to be recompressed is selected. And a decoder for decompressing program data compressed at the selected first compression rate in the storage unit, and the communication unit transfers the decompressed program data to the program recording device for decompression. The program data received from the program recording device is re-compressed at a compression rate higher than the first compression rate, and the recording control unit has a higher compression rate than the received first compression rate. Recompressed program data In replacing the data of the compressed program on the selected first compression rate in the storage unit.

  Preferably, the compression control unit replays the program data compressed at the first compression rate in the storage unit so that the desired free space can be secured when the desired free space does not exist in the storage unit. At least one to be compressed is selected, and the compression rate when re-compressing the data of the selected program is specified at a compression rate higher than the first compression rate, and the communication unit includes the decompressed program data The specified compression rate is transferred to the program recording device, and the program data compressed by the specified compression rate is received from the program recording device, and the recording control unit receives the specified compression rate. The program data recompressed in step (b) is replaced with the program data compressed at the selected first compression rate in the storage unit.

  Preferably, the communication unit receives the capacity of the compressed program data to be transferred next time from the program recording device, and the compression control unit has a free space for the notified capacity of the compressed program data to be transferred next time. At least one program data to be recompressed is selected and selected from the program data compressed at the first compression rate in the storage unit so that the free space can be secured when the capacity does not exist in the storage unit. The compression rate when recompressing the program data is specified at a compression rate higher than the first compression rate, and the communication unit transfers the specified compression rate together with the decompressed program data to the program recording device, The decompressed program data is received from the program recording device in which the program data is compressed at the specified compression rate, and the recording control unit selects the program data in the storage unit based on the received program data recompressed at the specified compression rate. First Replacing the data of the compressed program at a compression rate.

  Preferably, the compression control unit gives priority to the data of the program that has been viewed in the program reproducing apparatus as the data of the program compressed at the at least one first compression rate to be selected.

  Preferably, the compression control unit returns the compression rate to the first compression rate in the program data compressed at a higher compression rate than the first compression rate in the storage unit based on the free space in the storage unit. The communication unit selects at least one program data, the communication unit notifies the program recording device of the selected program data, receives the program data compressed at the first compression rate from the program recording device, and the recording control unit Replaces the program data compressed at a higher compression rate than the selected first compression rate in the storage unit with the received program data compressed at the first compression rate.

  Preferably, the compression control unit gives priority to data of an unviewed program in the program reproducing device as program data for returning at least one selected compression ratio to the first compression ratio.

  The program recording / playback system of the present invention is a program recording / playback system comprising a program recording device that does not have a decoding function and a program playback device that does not have an encoding function. A first storage unit for storing data; a tuner for receiving program data sent from a broadcasting station; an encoder for compressing received program data at a first compression rate; and compressed program data Is stored in the first storage unit, and a first communication unit for transferring the compressed program data to the program reproduction device, and the first communication unit is already a program reproduction device. The data of the program that has been decompressed at the first compression rate transferred to the program is decompressed from the program playback device, and the encoder receives the decompressed program data that is higher than the first compression rate. compression The first recording control unit stores the program data compressed at a compression rate higher than the first compression rate in the first storage unit, and the first communication unit performs the first compression. Program data compressed at a compression rate higher than the rate is transferred to the program playback device, and the program playback device is compressed from the program recording device by a second storage unit for storing compressed program data. A second communication unit that receives the data of the received program, a second recording control unit that stores the received compressed program data in the second storage unit, and a first compression rate in the second storage unit The first compression control unit that selects at least one of the program data compressed in step 1 to be recompressed, and the program data compressed at the selected first compression rate in the second storage unit are decompressed. And a second communication unit that stores the decompressed program data in the program recording device. The program data transferred and decompressed is re-compressed from the program recording device at a compression rate higher than the first compression rate, and the second recording control unit receives the received first compression. The program data recompressed at a compression rate higher than the rate is replaced with the program data compressed at the selected first compression rate in the second storage unit.

  According to the present invention, even when the program recording apparatus does not have a decoding function and the program reproduction apparatus does not have an encoding function, program data can be recompressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
In the first embodiment, the compressed program data is decompressed by the decoder of the program playback device, the decompressed program data is transmitted to the program recording device, and the decompressed program data is transmitted by the encoder of the program recording device. The present invention relates to a program recording / reproducing system for recompressing and transmitting to a program reproducing apparatus.

(Configuration of program recording / playback system)
FIG. 1 is a diagram showing the configuration of a program recording / playback system.

  Referring to FIG. 1, the program recording / playback system includes a program recording device 10 and a program playback device 20.

  The program recording apparatus 10 includes a compression control unit 11, a tuner 12, an encoder 13, a recording control unit 14, a main body storage unit 16, and a transfer unit 15.

  The compression control unit 11 controls the entire compression process of the program recording apparatus 10.

  The tuner 12 receives data of a program composed of analog video and audio data transmitted from a broadcasting station.

Encoder 13, the compression ratio alpha ₀ the data of the program, alpha _1, alpha _2, · · ·, compressed in one of alpha _N. Compression _{ratio, α 0, α 1, α} 2, ···, it becomes higher in the order of α _N. The compression rate is represented by the amount of data after compression / the amount of data before compression. When the compression rate is high, the amount of data after compression is small. The encoder 13 compresses the analog program data received by the tuner 12 into digital MPEG data. The compression rate at this time is α ₀ . Further, the encoder 13 recompresses the data of each program received from the program playback device 20 at a new compression rate specified for each program received from the program playback device 20. The compression rate at this time is any one of α ₁ , α ₂ ,..., Α _N.

  The main body storage unit 16 stores program data compressed by the encoder 13.

  The recording control unit 14 deletes, from the main body storage unit 16, data of one or more programs that have been notified to be recompressed from the program playback device 20 (data before recompression). The recording control unit 14 stores the recompressed program data (recompressed data) in the main body storage unit 16.

The transfer unit 15 transfers the program data received by the tuner 12 and compressed by the encoder 13 at the compression rate α ₀ to the program playback device 20. In addition, the transfer unit 15 receives notification of one or more programs to be recompressed and a new compression rate of each recompressed program. Further, the transfer unit 15 receives the data of one or more decompressed programs. In addition, the transfer unit 15 transfers the recompressed program data to the program playback device 20.

  The program playback device 20 includes a compression control unit 21, an operation input unit 22, a recording control unit 23, a terminal storage unit 26, a decoder 24, and a transfer unit 25.

  The operation input unit 22 receives from the user one or more programs to be recompressed among programs whose data is stored in the terminal storage unit 26, and designation of a new compression rate for each program to be recompressed.

  The compression control unit 21 controls the entire compression process of the program playback device 20. The compression control unit 21 sends to the transfer unit 25 one or more programs to be recompressed that have been designated by the user and a new compression rate for each program to be recompressed.

  The terminal storage unit 26 stores compressed program data transferred from the program recording apparatus 10.

  The recording control unit 23 deletes data of one or more programs to be recompressed from the terminal storage unit 26. The recording control unit 23 stores the recompressed program data in the terminal storage unit 26.

  The decoder 24 reads the data of one or more programs to be recompressed from the terminal storage unit 26 and decompresses the data.

  The transfer unit 25 notifies the program recording apparatus 10 of one or more programs to be recompressed, which are designated by the user, and the new compression rate of each program to be recompressed. Further, the transfer unit 25 transfers the data of one or more decompressed programs to the program recording device 10. In addition, the transfer unit 25 receives recompressed program data.

(Overview of recompression processing)
FIG. 2 is a diagram illustrating an outline of the recompression process according to the first embodiment.

  FIG. 2A shows the state of the program recording apparatus 10 before the start of the recompression process, and FIG. 2B shows the state of the program playback apparatus 20 before the start of the recompression process.

As shown in these figures, the program recording apparatus 10 and a program playback apparatus 20, the data A has been compressed at a compression rate alpha ₀ the program and the data B of the compressed program at a compression rate alpha ₀ is stored Yes.

  FIG. 2C shows the state of the program recording apparatus 10 at the time of notification of program data to be recompressed, and FIG. 2D shows the state of the program playback apparatus 20 at the time of notification of data of the program to be recompressed. To express.

As shown in these drawings, the program playback device 20 notifies the program recording device 10 of the recompression of the compressed program data A and the new compression rate α ₁ . Upon receiving this notification, the program recording apparatus 10 deletes the compressed program data A.

  FIG. 2E shows the state of the program recording apparatus 10 when the program data is decompressed and recompressed, and FIG. 2F shows the state of the program playback apparatus 20 when the program data is decompressed and recompressed. To express.

As shown in these drawings, the program playback device 20 decodes the compressed program data A and transfers the decompressed data to the program recording device 10. The program playback device 20 deletes the compressed program data A. The program recording apparatus 10 receives the decompressed data, recompresses this data at the compression rate α ₁ , stores the recompressed program data A ′, and transfers it to the program recording apparatus 10. The program recording apparatus 10 receives and stores the recompressed program data A ′.

  FIG. 2G shows the state of the program recording apparatus 10 after the end of the recompression process, and FIG. 2H shows the state of the program playback apparatus 20 after the end of the recompression process.

  As shown in these figures, the program recording device 10 and the program reproducing device 20 store recompressed program data A ′ and compressed program data B.

(Recompression operation)
FIG. 3 is a flowchart showing an operation procedure of recompression processing by the program recording / playback system according to the first embodiment.

  First, the operation input unit 22 of the program playback device 20 sets one or more programs to be recompressed among programs whose data is stored in the terminal storage unit 26 from the user, and a new compression rate for each program to be recompressed. Accept specification. This new compression rate is higher than the current compression rate of the program data. The compression control unit 21 of the program playback device 20 sends one or more programs to be recompressed in response to the designation designated by the user and the new compression rate of each program to be recompressed to the transfer unit 25 (step S101). .

  The transfer unit 25 of the program playback device 20 notifies the program recording device 10 of one or more programs to be recompressed specified by the user and the new compression rate of each program to be recompressed (step S102).

  The transfer unit 15 of the program recording apparatus 10 receives notification of one or more programs to be recompressed and a new compression ratio of each recompressed program. The recording control unit 14 of the program recording apparatus 10 deletes the data of one or more programs to be recompressed that have been notified from the main body storage unit 16 (step S103).

  Next, the decoder 24 of the program playback device 20 reads out the data of one or more programs to be recompressed from the terminal storage unit 26 and decompresses them. The transfer unit 25 of the program playback device 20 transfers the data of one or more decompressed programs to the program recording device 10 (step S104).

  The storage control unit of the program playback device 20 deletes the data of one or more programs to be recompressed from the terminal storage unit 26 (step S105).

  The transfer unit 15 of the program recording apparatus 10 receives the data of one or more decompressed programs. The encoder 13 of the program recording device 10 recompresses the data of each program at the new compression rate specified for each program received in step S102. The recording control unit 14 of the program recording apparatus 10 stores the recompressed program data in the main body storage unit 16. The transfer unit 15 of the program recording device 10 transfers the recompressed program data to the program playback device 20 (step S106).

  The transfer unit 25 of the program playback device 20 receives the recompressed program data. The recording control unit 23 of the program reproducing device 20 stores the recompressed program data in the terminal storage unit 26 (step S107).

  As described above, according to the program recording / playback system according to the first embodiment, even if the program recording device 10 does not have a decoding function and the program playback device 20 does not have an encoding function, Data can be recompressed.

[Second Embodiment]
In the second embodiment, when the user designates a desired free space in the storage unit in the mobile terminal, the program selected by selecting the program data to be recompressed in order to secure the free space Is decompressed by the decoder 24 of the program reproducing device 20, the decompressed program data is transmitted to the program recording device 10, the decompressed program data is recompressed by the encoder 13 of the program recording device 10, and the program is reproduced. The present invention relates to a program recording / playback system to be transmitted to the apparatus 20.

(Configuration of program recording / playback system)
Of the components of the program recording / playback system according to the second embodiment, differences from the program recording / playback system according to the first embodiment will be described.

  First, the operation input unit 22 of the program playback device 20 accepts designation of a desired free space ESU in the terminal storage unit 26 from the user.

  The compression control unit 21 of the program playback device 20 does not perform recompression when the current free space ES0 of the terminal storage unit 26 is equal to or larger than the free space ESU designated by the user.

When the current free space ES0 of the terminal storage unit 26 is less than the free space ESU specified by the user, the compression control unit 21 of the program playback device 20 stores the desired free space in the terminal storage unit 26. Among the program data compressed at the compression rate α ₀ , at least one of the program data to be re-compressed is selected, and the compression rate when re-compressing the data of the selected program is set to α ₁ , α ₂ ,. Specify one of α _N.

(Recompression operation)
FIG. 4 is a flowchart showing an operation procedure of recompression processing by the program recording / playback system according to the second embodiment.

  First, the operation input unit 22 of the program playback device 20 accepts designation of a desired free space ESU in the terminal storage unit 26 from the user (step S201).

  When the current free space ES0 in the terminal storage unit 26 is equal to or larger than the free space ESU specified by the user (NO in step S202), the compression control unit 21 of the program playback device 20 does not perform recompression.

  When the current free space ES0 of the terminal storage unit 26 is less than the free space ESU specified by the user (YES in step S202), the compression control unit 21 of the program playback device 20 performs recompression by the following steps S203 to S214. Let it be done.

  The compression control unit 21 of the program playback device 20 sets the compression rate control variable n to 1 (step S203).

The compression control unit 21 of the program playback device 20 checks whether or not the compression rate α _n is specified for all programs among the programs whose data is stored in the terminal storage unit 26 (step S204).

When the compression rate α _n is specified for all programs (NO in step S204), the compression control unit 21 of the program playback device 20 increments the compression control variable n by 1 (step S205), and the process proceeds to step S204. Return.

When there is a program for which the compression rate α _n is not specified (YES in step S204), the compression control unit 21 of the program playback device 20 selects one program from these programs and newly adds it to the program. Specify a specific compression ratio α _n . At the time of selection, if there is a program that has been viewed among those programs, it is selected, and if there is no program that has been viewed, an unviewed program is selected (step S206).

The compression control unit 21 of the program playback device 20 re-compresses, that is, re-compresses the data of each program for which a new compression rate is designated at the compression rate designated for the program, and compresses the re-compressed program data. The free capacity ES1 of the terminal storage unit 26 is calculated when it is replaced with the pre-recompressed program data compressed at the rate α ₀ and stored in the terminal storage unit 26.

That is, the free space ES1 is {ES0 + the amount of uncompressed data for the recording time of all programs for which a new compression rate is specified × α ₀ −Σthe recording time for each program for which a new compression rate is specified. The amount of uncompressed data x the new compression rate specified for the program}. Here, the new compression rate designated for the program is any one of α ₁ , α ₂ ,..., Α _n (step S207).

  When the free capacity ES1 of the terminal storage unit 26 when recompressed is less than the free capacity ESU designated by the user (NO in step S208), the compression control unit 21 of the program playback device 20 returns to step S204.

  When the free capacity ES of the terminal storage unit 26 when recompressed is equal to or larger than the free capacity ESU specified by the user (YES in step S208), the compression control unit 21 of the program playback device 20 recompresses the data to the transfer unit 25 1 The program recording apparatus 10 is notified of the new compression rate of the programs to be recompressed and more than one program (step S209).

  Next, the transfer unit 15 of the program recording apparatus 10 receives notification of one or more programs to be recompressed and a new compression ratio of each recompressed program. The recording control unit 14 of the program recording apparatus 10 deletes the program data to be recompressed from the main body storage unit 16 (step S210).

  Next, the decoder 24 of the program playback device 20 reads out the data of one or more programs to be recompressed from the terminal storage unit 26 and decompresses them. The transfer unit 25 of the program playback device 20 transfers the data of one or more decompressed programs to the program recording device 10 (step S211).

  The recording control unit 23 of the program reproduction device 20 deletes data of one or more programs to be recompressed from the terminal storage unit 26 (step S212).

  The transfer unit 15 of the program recording apparatus 10 receives the data of one or more decompressed programs. The encoder 13 of the program recording apparatus 10 recompresses the data of each program at the compression rate specified for each program received in step S111. The recording control unit 14 of the program recording apparatus 10 stores the recompressed program data in the main body storage unit 16. The transfer unit 15 of the program recording device 10 transfers the recompressed program data to the program playback device 20 (step S213).

  The transfer unit 25 of the program playback device 20 receives the recompressed program data. The recording control unit 23 of the program reproduction device 20 stores the recompressed program data in the terminal storage unit 26 (step S214).

  As described above, according to the program recording / playback system according to the second embodiment, even if the program recording device 10 does not have a decoding function and the program playback device 20 does not have an encoding function, Data can be recompressed to secure a free space as desired by the user.

[Third Embodiment]
In the third embodiment, recompression is performed before transfer for the purpose of securing free space in the storage unit in the portable terminal for storing program data to be transferred from the program recording device 10 to the program playback device 20. The program data to be selected is selected, the selected program data is decompressed by the decoder 24 of the program playback device 20, the decompressed program data is transmitted to the program recording device 10, and the encoder 13 of the program recording device 10 is transmitted. The present invention relates to a program recording / reproducing system for recompressing data of a decompressed program and transmitting it to a program reproducing device 20.

(Configuration of program recording / playback system)
Of the components of the program recording / playback system according to the third embodiment, differences from the program recording / playback system according to the first embodiment will be described.

The compression control unit 11 of the program recording apparatus 10 calculates the total recording time of the next program group PG to be transferred. The compression control unit 11 of the program recording device 10 calculates the data size PS of the program group PG by multiplying the compression rate α ₀ and the data amount at the time of non-compression for the total recording time. The compression control unit 11 of the program recording device 10 instructs the transfer unit 15 of the program recording device 10 when the current free space ES0 of the terminal storage unit 26 of the program playback device 20 is less than the data size PS of the program group PG. Then, a recompression request is transmitted to the program playback device 20 together with the data size PS of the program group PG.

  The transfer unit 25 of the program playback device 20 receives the recompression request together with the data size of the program group PG.

The compression control unit 21 of the program playback device 20 can secure the free space when there is no free space in the terminal storage unit 26 for storing the compressed program data transferred from the program recording device 10 next time. As described above, at least one program data to be recompressed is selected from the program data compressed at the compression rate α ₀ in the terminal storage unit 26, and the compression rate when the selected program data is recompressed is expressed by α Designate _{one of 1} , α ₂ ,..., Α _N.

(Overview of recompression processing)
FIG. 5 is a diagram illustrating an outline of the recompression processing according to the third embodiment.

  FIG. 5A shows the state of the program recording apparatus 10 before the start of the recompression process, and FIG. 5B shows the state of the program playback apparatus 20 before the start of the recompression process.

As shown in these figures, the program recording apparatus 10 and a program playback apparatus 20, the data A has been compressed at a compression rate alpha ₀ the program and the data B of the compressed program at a compression rate alpha ₀ is stored Yes. The program recording apparatus 10 stores program data C compressed at the compression rate α ₀ , but has not yet been transferred to the program playback apparatus 20.

  FIG. 5C shows the state of the program recording apparatus 10 at the time of notification of the data of the program to be recompressed, and FIG. 5D shows the state of the program playback apparatus 20 at the time of notification of the data of the program to be recompressed. To express.

As shown in these drawings, the program playback device 20 notifies the program recording device 10 of the recompression of the compressed program data A and the new compression rate α ₁ . Upon receiving this notification, the program recording apparatus 10 deletes the compressed program data A.

  FIG. 5E shows the state of the program recording apparatus 10 when the program data is decompressed and recompressed, and FIG. 5F shows the state of the program playback apparatus 20 when the program data is decompressed and recompressed. To express.

As shown in these drawings, the program playback device 20 decodes the compressed program data A and transfers the decompressed data to the program recording device 10. The program playback device 20 deletes the compressed program data A. The program recording apparatus 10 receives the decompressed data, recompresses this data at the compression rate α ₁ , stores the recompressed program data A ′, and transfers it to the program recording apparatus 10. The program recording apparatus 10 receives and stores the recompressed program data A ′.

  FIG. 5G shows the state of the program recording apparatus 10 after the end of the recompression process, and FIG. 5H shows the state of the program playback apparatus 20 after the end of the recompression process.

  As shown in these figures, the program recording device 10 and the program reproducing device 20 store recompressed program data A ′ and compressed program data B. The program recording apparatus 10 stores program data C before being transferred to the program reproducing apparatus 20.

  FIG. 5 (i) shows the state of the program recording device 10 when the program data is transferred, and FIG. 5 (j) shows the state of the program playback device 20 when the program data is transferred.

  As shown in these figures, the program recording apparatus 10 transfers the compressed program data C to the program reproduction apparatus 20. The program playback device 20 receives and stores program data C.

(Recompression and transfer of new program data)
FIG. 6 is a flowchart showing an operation procedure of recompression and new program data transfer processing by the program recording / playback system according to the third embodiment.

Referring to FIG. 6, tuner 12 of program recording apparatus 10 receives data of a program reserved according to a reservation schedule. The encoder 13 of the program recording apparatus 10 compresses the received program data at the compression rate α ₀ . The recording control unit 14 of the program recording apparatus 10 stores the program data compressed at the compression rate α ₀ in the main body storage unit 16 (step S301).

The compression control unit 11 of the program recording apparatus 10 calculates the total recording time of the program group PG to be recorded the next day and transferred next time at a predetermined night time, for example, 2:00 am. The compression control unit 11 of the program recording device 10 calculates the data size PS of the program group PG by multiplying the compression rate α ₀ and the amount of uncompressed data for the total recording time (step S302).

  The compression control unit 11 of the program recording device 10 does not perform recompression when the current free space ES0 of the terminal storage unit 26 of the program playback device 20 is equal to or larger than the data size PS of the program group PG (NO in step S303). .

  When the current free space ES0 of the terminal storage unit 26 of the program playback device 20 is less than the data size PS of the program group PG (YES in step S303), the compression control unit 11 of the program recording device 10 performs the following steps S304 to S304. In step S315, recompression is performed.

  The transfer unit 15 of the program recording device 10 transmits a recompression request together with the data size PS of the program group PG to the program reproduction device 20 (step S304).

  The transfer unit 25 of the program playback device 20 receives the recompression request together with the data size of the program group PG. The compression control unit 21 of the program playback device 20 sets the compression rate control variable n to 1 (step S305).

The compression control unit 21 of the program playback device 20 checks whether or not the compression rate α _n is specified for all programs among the programs whose data is stored in the terminal storage unit 26 (step S306).

When the compression rate α _n is specified for all programs (NO in step S306), the compression control unit 21 of the program playback device 20 increments the compression control variable n by 1 (step S307), and the process proceeds to step S305. Return.

When there is a program for which the compression rate α _n is not specified (YES in step S306), the compression control unit 21 of the program playback device 20 selects one program from these programs and newly adds the program to the program. Specify a specific compression ratio α _n . At the time of selection, if there is a program that has been viewed among those programs, it is selected, and if there is no program that has been viewed, an unviewed program is selected (step S308).

The compression control unit 21 of the program playback device 20 re-compresses, that is, re-compresses the data of each program for which a new compression rate is designated at the compression rate designated for the program, and compresses the re-compressed program data. The free capacity ES1 of the terminal storage unit 26 is calculated when it is replaced with the pre-recompressed program data compressed at the rate α ₀ and stored in the terminal storage unit 26. That is, the free space ES1 is {ES0 + the amount of uncompressed data for the recording time of all programs for which a new compression rate is specified × α ₀ −Σthe recording time for each program for which a new compression rate is specified. The amount of uncompressed data x the new compression rate specified for the program}. Here, the new compression rate designated for the program is any one of α ₁ , α ₂ ,..., Α _n (step S309).

  When the free capacity ES1 of the terminal storage unit 26 when recompressed is less than the data size PS of the program group PG (NO in step S310), the compression control unit 21 of the program playback device 20 returns to step S306.

  When the free capacity ES1 of the terminal storage unit 26 when recompressed is equal to or larger than the data size PS of the program group PG (YES in step S310), the compression control unit 21 of the program playback device 20 recompresses to the transfer unit 25 1 The program recording apparatus 10 is notified of the new compression rate of the programs to be recompressed and the one or more programs (step S311).

  Next, the transfer unit 15 of the program recording apparatus 10 receives notification of one or more programs to be recompressed and a new compression ratio of each recompressed program. The recording control unit 14 of the program recording apparatus 10 deletes the program data to be recompressed from the main body storage unit 16 (step S312).

  Next, the decoder 24 of the program playback device 20 reads out the data of one or more programs to be recompressed from the terminal storage unit 26 and decompresses them. The transfer unit 25 of the program playback device 20 transfers the decompressed data of one or more programs to the program recording device 10 (step S313).

  The recording control unit 23 of the program playback device 20 deletes data of one or more programs to be recompressed from the terminal storage unit 26 (step S314).

  The transfer unit 15 of the program recording apparatus 10 receives the data of one or more decompressed programs. The encoder 13 of the program recording apparatus 10 recompresses the data of each program at the compression rate specified for each program received in step S311. The recording control unit 14 of the program recording apparatus 10 stores the recompressed program data in the main body storage unit 16. The transfer unit 15 of the program recording apparatus 10 transmits the recompressed program data to the program reproduction apparatus 20 (step S315).

  The transfer unit 25 of the program playback device 20 receives the recompressed program data. The recording control unit 23 of the program playback device 20 stores the recompressed program data in the terminal storage unit 26 (step S316).

The transfer unit 15 of the program recording device 10 transmits the program data of the program group PG compressed at the compression rate α ₀ to the program reproduction device 20 at a predetermined time at night, for example, 3:00 am (step S317).

The transfer unit 25 of the program playback device 20 receives the program data of the program group PG compressed at the compression rate α ₀ . The recording control unit 23 of the program reproduction device 20 stores the program in the data terminal storage unit 26 of the program group PG compressed at the compression rate α ₀ (step S318).

  As described above, according to the program recording / playback system according to the third embodiment, even if the program recording device 10 does not have a decoding function and the program playback device 20 does not have an encoding function, By recompressing the data, it is possible to secure a free space for storing the data of the compressed program transferred from the program recording device 10 next time.

[Fourth Embodiment]
In the fourth embodiment, when the free space of the program playback device increases due to deletion of program data or the like, program data obtained by compressing program data recompressed at a high compression rate at the original low compression rate The present invention relates to a program recording / playback system having a function of replacing with.

(Configuration of program recording / playback system)
Of the components of the program recording / playback system according to the fourth embodiment, differences from the program recording / playback system according to the third embodiment will be described.

  When the free capacity ES1 of the terminal storage unit 26 when recompressed is equal to or larger than the data size PS of the program group PG, the compression control unit 21 of the program playback device 20 includes one or more programs to be recompressed by the transfer unit 25 and each of the programs. Instead of notifying the program recording device 10 of the new compression rate of the program to be recompressed, the transfer unit 15 of the program recording device 10 notifies one or more programs to be recompressed and the new compression rate of each recompressed program. The recording control unit 14 of the program recording apparatus 10 does not delete the program data to be recompressed from the main body storage unit 16.

  The operation input unit 22 of the program playback device 20 accepts designation of one or more programs to be deleted from among programs whose data are stored in the terminal storage unit 26 from the user.

The recording control unit 23 of the program playback device 20 deletes the program data designated by the user from the terminal storage unit 26. The recording control unit 23 of the program playback device 20 deletes the data of the program designated to change the compression rate to α ₀ from the terminal storage unit 26. The recording control unit 23 of the program playback device 20 stores the received program data compressed at the compression rate α ₀ in the terminal storage unit 26.

The compression control unit 21 of the program playback device 20 determines the compression rate of the program data compressed at a compression rate other than the compression rate α ₀ in the terminal storage unit 26 based on the free space in the terminal storage unit 26. At least one program data to be returned to α ₀ is selected.

The communication unit of the program playback device 20 notifies the program recording device 10 of the data of the selected program. Further, the communication unit of the program playback device 20 receives program data compressed at the compression rate α ₀ from the program recording device 10.

The communication unit of the program recording device 10 receives from the program playback device 20 an instruction to select program data that returns the compression rate to α ₀ , and receives program data compressed at the data compression rate α ₀ of the selected program. The data is read from the main body storage unit 16 and transferred to the program playback device 20.

(Overview of recompression processing)
FIG. 7 is a diagram illustrating an outline of the recompression processing according to the fourth embodiment.

  FIG. 7A shows the state of the program recording device 10 at the time of notification of the data of the program to be recompressed, and FIG. 7B shows the state of the program playback device 20 at the time of notification of the data of the program to be recompressed. To express.

As shown in these figures, the program recording apparatus 10 and a program playback apparatus 20, the data A has been compressed at a compression rate alpha ₀ the program and the data B of the compressed program at a compression rate alpha ₀ is stored Yes. The program recording apparatus 10 stores program data C compressed at the compression rate α ₀ , but has not yet been transferred to the program playback apparatus 20.

The program reproducing device 20 notifies the program recording device 10 of the recompression of the compressed program data A and the new compression rate α ₁ . Unlike the third embodiment, the program recording apparatus 10 does not delete the compressed program data A even when this notification is received.

  FIG. 7C shows the state of the program recording apparatus 10 at the time of decompression and recompression of program data, and FIG. 7D shows the state of the program playback apparatus 20 at the time of decompression and recompression of program data. To express.

As shown in these drawings, the program playback device 20 decodes the compressed program data A and transfers the decompressed data to the program recording device 10. The program playback device 20 deletes the compressed program data A. The program recording apparatus 10 receives the decompressed data, recompresses this data at the compression rate α ₁ , stores the recompressed program data A ′, and transfers it to the program recording apparatus 10. The program recording apparatus 10 receives and stores the recompressed program data A ′.

  FIG. 7E shows the state of the program recording apparatus 10 after the end of the recompression process, and FIG. 7F shows the state of the program playback apparatus 20 after the end of the recompression process.

  As shown in these drawings, the program recording apparatus 10 is recompressed with the compressed program data A, the compressed program data B, the program data C before being transferred to the program reproduction apparatus 20, and the like. Program data A 'is stored. The program playback apparatus 20 stores recompressed program data A ′ and compressed program data B.

  FIG. 7G shows the state of the program recording device 10 when the program data is transferred, and FIG. 7H shows the state of the program playback device 20 when the program data is transferred.

  As shown in these figures, the program recording apparatus 10 transfers the compressed program data C to the program reproduction apparatus 20. The program playback device 20 receives and stores program data C.

  FIG. 7 (i) shows the state of the program recording device 10 when the user deletes the program data, and FIG. 7 (j) shows the state of the program playback device 20 when the user deletes the program data.

  As shown in these drawings, in the program reproducing device 20, the compressed program data C is deleted.

  FIG. 7 (k) shows the state of the program recording device 10 when the program data is transferred, and FIG. 7 (l) shows the state of the program playback device 20 when the program data is transferred.

  As shown in these figures, since the free space has increased in the storage unit in the program playback device 20, it is possible to store program data A having a low compression rate instead of program data A ′ having a high compression rate. As a result, the program recording apparatus 10 transfers the data A of the program with a low compression rate. The program reproducing device 20 receives data A of a program with a low compression rate, deletes data A ′ of a program with a high compression rate, and stores data A of a program with a low compression rate.

(Recompression and transfer of new program data)
FIG. 8 is a flowchart showing an operation procedure of recompression and data transfer processing of a new program by the program recording / playback system according to the fourth embodiment.

  Referring to FIG. 8, the operation procedure of FIG. 8 is different from the operation procedure of the third embodiment shown in FIG. 6 in that steps S311 and S312 are not provided. Is to execute.

  In other words, the compression control unit 21 of the program playback device 20 recompresses the transfer unit 25 when the free capacity ES1 of the terminal storage unit 26 when recompressed is equal to or larger than the data size PS of the program group PG (YES in step S310). The program recording apparatus 10 is not notified of one or more programs to be executed and the new compression rate of each recompressed program.

  Then, the transfer unit 15 of the program recording device 10 does not receive notification of one or more programs to be recompressed and the new compression rate of each recompressed program, and the recording control unit 14 of the program recording device 10 performs the recompression. The program data to be deleted is not deleted from the main body storage unit 16.

  If YES in step S310, the decoder 24 of the program playback device 20 reads data from one or more programs to be recompressed from the terminal storage unit 26 and decompresses them. The transfer unit 25 of the program playback device 20 transfers the data of one or more decompressed programs to the program recording device 10 (step S314).

(Original compressed data decompression process)
FIG. 9 is a flowchart showing the operation procedure of the original compressed data decompression process by the program recording / playback system according to the fourth embodiment.

  Referring to FIG. 9, operation input unit 22 of program playback device 20 accepts designation of one or more programs to be deleted from programs whose data is stored in terminal storage unit 26 from the user (step S401).

  The recording control unit 23 of the program playback device 20 deletes the data of the designated program from the terminal storage unit 26 (step S402).

  The compression control unit 21 of the program playback device 20 acquires the current free space ES0 of the terminal storage unit 26 after deletion of the program data (step S403).

The compression control unit 21 of the program playback device 20 includes programs that are not specified to change the compression rate to α ₀ among the programs recorded in the terminal storage unit 26 with a compression rate other than α _0. It is checked whether or not there is (step S404).

When there is a program that is not designated to change the compression ratio to α ₀ (YES in step S404), the compression control unit 21 of the program playback device 20 selects one program from these programs. At the time of selection, if there is a program of an unviewed program among those programs, it is selected, and if there is no program of an unviewed program, a viewed program is selected (step S405).

The compression control unit 21 of the program playback device 20 has the free space ES1 of the terminal storage unit 26 when the compression rate of the program designated to change the compression rate to α ₀ and the currently selected program is changed to α _0. Is calculated.

The free space ES1 is {ES0-Σdata amount at the time of non-compression for the recording time of each program designated to change the compression rate to α ₀ × (α ₀ -current compression rate of the program) -selection The amount of uncompressed data for the recording time of the recorded program × (α ₀ −the current compression rate of the program) is calculated here, where the current compression rate of the program data is α ₁ , α ₂ ,..., Α _N (step S406).

When the free space ES1 is 0 or more (YES in step S407), the compression control unit 21 of the program playback device 20 specifies to change the compression rate of the selected program to α ₀ (step S408).

  When the free space ES1 exceeds 0 (NO in step S409), the compression control unit 21 of the program playback device 20 returns to step S404.

  When the free space ES1 is less than 0 (NO in step S407) and when the free space ES1 is 0 (YES in step S409), the compression control unit 21 of the program playback device 20 finishes specifying the compression rate change. .

Next, the transfer unit 25 of the program playback device 20 notifies the program recording device 10 of the program designated to change the compression rate to α ₀ (step S410).

The recording control unit 23 of the program playback device 20 deletes the data of the program designated to change the compression rate to α ₀ from the terminal storage unit 26 (step S411).

The transfer unit 15 of the program recording apparatus 10 reads the data of the notified program that has been compressed at the compression rate α ₀ from the main body storage unit 16 and distributes the data to the program playback apparatus 20. (Step S412).

The transfer unit 25 of the program playback device 20 receives program data compressed at the compression rate α ₀ . The recording control unit 23 of the program playback device 20 stores the program in the data terminal storage unit 26 of the program compressed at the compression rate α ₀ (step S413).

  As described above, according to the program recording / playback system of the fourth embodiment, the program recording device 10 does not have a decoding function and the program playback device 20 has an encoding function, as in the third embodiment. Even if it is not, it is possible to recompress the program data and to secure a free space for storing the compressed program data transferred from the program recording apparatus 10 next time. In addition, when the program recording device 10 re-compresses the program data at a high compression rate, the program recording device 10 retains the program data compressed at the original low compression rate without deleting it. Can be replaced with high-quality program data with a low compression ratio.

(Modification)
The present invention is not limited to the above embodiment, and includes, for example, the following modifications.

(1) Notification of compression rate of recompression In the embodiment of the present invention, the program reproduction device notifies the program recording device of the compression rate when recompressing program data. However, the present invention is not limited to this. is not. The program recording apparatus may recompress the program data at a predetermined compression rate.

(2) Recompression timing In the embodiment of the present invention, after the program is recorded, the program data to be transferred, which is the data of the recorded program, is stored in the program playback device before being transferred to the program playback device. Although the data of the program is recompressed, the present invention is not limited to this. When the capacity of the main body storage unit of the program recording device is not large, the program data stored in the program reproducing device may be recompressed before recording the program.

(3) Priority program In the embodiment of the present invention, a program that has already been viewed is prioritized as a program to be recompressed, and a program that is not viewed as a program that returns to the original compression rate α ₀ when the free space in the terminal storage unit increases. Although priority was given to programs, this is not a limitation. For example, priority may be given to a program specified by the user, or priority may be given to a program belonging to a genre selected by the user. Further, as the program to be restored to the original compression rate α ₀ when the free space in the terminal storage unit increases, the program data having a higher compression rate may be selected in order.

(4) Method of selecting program to be recompressed In the second to fourth embodiments of the present invention, the minimum necessary program data is recompressed in order to secure free space, but the present invention is not limited to this. . For example, the free space is calculated when the data of all viewed programs is recompressed at the compression rate α ₁ . If the free space is insufficient, all the data of the viewing already program recompressed at a compression rate alpha _1, and calculates the available capacity when recompressing all program data unviewed at a compression rate alpha ₁ . If this even free space is insufficient, all of the data of the viewing pre-program and re-compressed in the compression rate α _2, and the free space at the time of the re-compression all of the program of data unviewed at a compression rate of α ₁ calculate. If this even free space is insufficient, all of the data of the viewing pre-program and re-compressed in the compression rate α _2, and the free space at the time of the re-compression all of the program of data unviewed at a compression rate of α ₂ calculate. Hereinafter, the compression rate is increased until the necessary free space can be secured.

(5) Program Data In the embodiment of the present invention, program data consisting of video and audio is received from a broadcast station, and program data consisting of video and audio is compressed in MPEG format. However, the present invention is limited to this. It is not a thing. For example, program data (music data) consisting only of audio from a broadcasting station may be received, and program data consisting only of audio may be compressed in MP3 (MPEG Audio Layer-3) format.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the structure of a program recording / reproducing system. It is a figure showing the outline | summary of the recompression process of 1st Embodiment. It is a flowchart showing the operation | movement procedure of the recompression process by the program recording / reproducing system which concerns on 1st Embodiment. It is a flowchart showing the operation | movement procedure of the recompression process by the program recording / reproducing system which concerns on 2nd Embodiment. It is a figure showing the outline | summary of the recompression process of 3rd Embodiment. It is a flowchart showing the operation | movement procedure of the recompression by the program recording / reproducing system which concerns on 3rd Embodiment, and the transfer process of the data of a new program. It is a figure showing the outline | summary of the recompression process of 4th Embodiment. It is a flowchart showing the operation | movement procedure of the recompression by the program recording / reproducing system which concerns on 4th Embodiment, and the transfer process of the data of a new program. It is a flowchart showing the operation | movement procedure of the original compression data decompression | restoration process by the program recording / reproducing system which concerns on 4th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Program recording device, 11, 21 Compression control part, 12 Tuner, 13 Encoder, 14, 23 Recording control part, 15, 25 Transfer part, 16 Main body memory | storage part, 20 Program reproducing | regenerating apparatus, 22 Operation input part, 24 Decoder, 26 Terminal storage unit.

Claims (12)

A program recording device having no decoding function,
A storage unit for storing compressed program data;
A tuner for receiving program data sent from a broadcasting station;
An encoder for compressing the received program data at a first compression rate;
A recording control unit for storing the compressed program data in the storage unit;
A communication unit for transferring the compressed program data to the program playback device,
The communication unit receives program data from the program playback device, which has already been transferred to the program playback device and decompressed program data compressed at the first compression rate,
The encoder compresses the received decompressed program data at a compression rate higher than a first compression rate;
The recording control unit stores program data compressed at a compression rate higher than the first compression rate in the storage unit,
The communication unit transfers the program data compressed at a compression rate higher than the first compression rate to the program reproduction device. The program recording device further includes:
It is checked whether or not a free space for storing compressed program data to be transferred next time to the program playback device exists in the storage unit of the program playback device. If the free space does not exist, the communication is performed. The program recording apparatus according to claim 1, further comprising: a compression control unit that instructs a program to notify the program reproducing apparatus of a capacity of data of the compressed program to be transferred next time. The communication unit receives from the program playback device designation of a compression rate when recompressing the program data together with the decompressed program data,
The specified compression ratio is higher than the first compression ratio;
The encoder compresses the received decompressed program data at the specified compression rate,
The program recording apparatus according to claim 1, wherein the communication unit transfers program data compressed at the designated compression rate to the program reproduction apparatus.   The recording control unit further receives the program data from the program playback device when receiving the program data decompressed from the program data compressed at the first compression rate that has already been transferred to the program playback device. 2. The program recording apparatus according to claim 1, wherein the program data compressed at the first compression rate transferred to the reproduction apparatus is deleted from the storage unit. The recording control unit is further configured to receive the program data from the program playback device in which the program data compressed at the first compression rate that has already been transferred to the program playback device is received from the program playback device. Without deleting the program data compressed at the first compression rate transferred to the program playback device from the storage unit;
The communication unit receives an instruction to select program data for returning the compression rate to the first compression rate from the program reproducing device, and the data of the program instructed to be selected is compressed at the first compression rate. The program recording apparatus according to claim 1, wherein data is read from the storage unit and transferred to the program reproducing apparatus. A program playback device having no encoding function,
A storage unit for storing compressed program data;
A communication unit for receiving compressed program data from the program recording device;
A recording control unit for storing the received compressed program data in the storage unit;
A compression control unit that selects at least one program data to be recompressed from the program data compressed at the first compression rate in the storage unit;
A decoder for decompressing data of the program compressed at the selected first compression rate in the storage unit,
The communication unit transfers the decompressed program data to the program recording apparatus, and the decompressed program data is recompressed at a compression rate higher than the first compression rate. Received from the program recorder,
The recording control unit replaces the program data compressed at the selected first compression rate in the storage unit with the program data recompressed at a higher compression rate than the received first compression rate. Program playback device. The compression control unit includes the program data compressed at the first compression rate in the storage unit so that the desired free space can be secured when the desired free space does not exist in the storage unit. Selecting at least one to be recompressed, and specifying a compression rate when recompressing the data of the selected program at a compression rate higher than the first compression rate,
The communication unit transfers the specified compression rate together with the decompressed program data to the program recording apparatus, and the program data in which the decompressed program data is compressed at the specified compression rate is transferred to the program recording device. Received from the program recorder,
The program according to claim 6, wherein the recording control unit replaces the data of the program compressed at the selected first compression rate in the storage unit with the received program data recompressed at the specified compression rate. Playback device. The communication unit receives the volume of compressed program data transferred next time from the program recording device,
The compression control unit is configured to store the free space in the storage unit so that the free space can be secured when there is no free space in the storage unit for the compressed program data to be transferred next time. At least one program data to be recompressed is selected from the program data compressed at a compression rate of 1, and the compression rate when recompressing the selected program data is higher than the first compression rate. As a percentage,
The communication unit transfers the specified compression rate together with the decompressed program data to the program recording apparatus, and the program data in which the decompressed program data is compressed at the specified compression rate is transferred to the program recording device. Received from the program recorder,
The program according to claim 6, wherein the recording control unit replaces the data of the program compressed at the selected first compression rate in the storage unit with the received program data recompressed at the specified compression rate. Playback device.   The program playback device according to claim 6, wherein the compression control unit gives priority to data of a program that has been viewed in the program playback device as data of the program compressed at the at least one first compression rate to be selected. The compression control unit returns the compression rate to the first compression rate among program data compressed at a compression rate higher than the first compression rate in the storage unit, based on the free space in the storage unit. Select at least one program data,
The communication unit notifies the program recording device of data of the selected program, receives data of the program compressed at the first compression rate from the program recording device,
The recording control unit replaces program data compressed at a higher compression rate than the selected first compression rate in the storage unit with the received program data compressed at the first compression rate. Item 7. The program playback device according to Item 6.   11. The program reproduction device according to claim 10, wherein the compression control unit gives priority to data of an unviewed program in the program reproduction device as program data for returning the selected at least one compression rate to the first compression rate. A program recording / playback system comprising a program recording device not having a decoding function and a program playback device not having an encoding function,
The program recording device comprises:
A first storage unit for storing compressed program data;
A tuner for receiving program data sent from a broadcasting station;
An encoder for compressing the received program data at a first compression rate;
A first recording control unit for storing the compressed program data in the first storage unit;
A first communication unit for transferring the compressed program data to the program playback device;
The first communication unit receives, from the program reproduction device, program data obtained by decompressing program data compressed at the first compression rate that has already been transferred to the program reproduction device;
The encoder compresses the received decompressed program data at a compression rate higher than a first compression rate;
The first recording control unit stores program data compressed at a compression rate higher than the first compression rate in the first storage unit,
The first communication unit transfers program data compressed at a compression rate higher than the first compression rate to the program playback device,
The program playback device comprises:
A second storage unit for storing compressed program data;
A second communication unit for receiving compressed program data from the program recording device;
A second recording control unit for storing the received compressed program data in the second storage unit;
A first compression control unit that selects at least one program data to be recompressed from the program data compressed at the first compression rate in the second storage unit;
A decoder for decompressing program data compressed at the selected first compression rate in the second storage unit;
The second communication unit transfers the decompressed program data to the program recording apparatus, and the decompressed program data is recompressed at a compression rate higher than the first compression rate. Receiving data from the program recording device;
The second recording control unit is compressed at the selected first compression rate in the second storage unit with program data recompressed at a higher compression rate than the received first compression rate. A program recording and playback system that replaces program data.

Images