Method and device for ensuring storage time for digital broadcast

• US 20040141718A1
• Filed: 10/27/2003
• Published: 07/22/2004
• Est. Priority Date: 01/22/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Watabe, Akihiro, Miyagoshi, Eiji
• Granted Patent: US 7,359,615 B2
• Time in Patent Office: Days
• US Class Current: 386/46
• CPC Class Codes: G11B 20/00007 Time or data compression or expansion audio compression based on psychoacoustics G10L19/00; data processing for reproducing audio data at different playback speeds G10L21/04; video compression H04N19/00; data compression per se H03M7/30
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: G11B 2020/00079 the compression ratio or quality level being adapted to circumstances, e.g. to the available recording space
• CPC Class Codes: G11B 2220/216 Rewritable discs
• CPC Class Codes: G11B 2220/218 Write-once discs
• CPC Class Codes: G11B 2220/2541 Blu-ray discs; Blue laser DVR discs
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 2220/2575 DVD-RAMs
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/587 involving temporal sub-sampling or interpolation, e.g. decimation or subsequent interpolation of pictures in a video sequence
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/234363 by altering the spatial resolution, e.g. for clients with a lower screen resolution
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4424 Monitoring of the internal components or processes of the client device, e.g. CPU or memory load, processing speed, timer, counter or percentage of the hard disk space used error monitoring in general G06F11/30; arrangements for monitoring conditions of receiving stations in broadcast systems H04H60/32; diagnosis, testing or measuring for television receivers H04N17/04
• CPC Class Codes: H04N 5/76 : Television signal recording
• CPC Class Codes: H04N 5/781 : on disks or drums
• CPC Class Codes: H04N 5/85 : on discs or drums
• CPC Class Codes: H04N 9/8042 : involving data reduction

Abstract

When a digitized broadcast is recorded in a storage medium, a required capacity of the storage medium is firstly calculated on the basis of a bit-rate of digitized broadcast data and a recording time which is known in advance. If the remaining capacity of the storage medium is smaller than the required capacity of the storage medium, for example, a frame rate decimation and pixel reduction are performed upon a broadcast to be newly stored, a re-encoding processing is performed for the broadcast and then the resultant broadcast is stored in the storage medium. If the remaining storage capacity of the storage medium is larger than the required capacity of the storage medium and thus remains, a frame interpolation and pixel interpolation are performed for the broadcast to be stored and then a re-encoding processing is performed for the resultant broadcast in order to improve its image quality. As a result, recording of the broadcast data in the storage medium can be ensured.

Claims

1. A method for ensuring a storage time for digital broadcast at the time of storing data for a digitized and then transmitted broadcast, comprising the steps of:

monitoring a predetermined recording time for the broadcast and a bit-rate of the broadcast and calculating, in real time, a required capacity of a storage medium;

determining whether or not said calculated required capacity of the storage medium can be contained within an empty area or a freely limited area of the storage medium;

if said calculated required capacity of the storage medium cannot be contained as the result of said determination, converting, in real time, said bit-rate of the broadcast into a smaller one; and

storing said converted broadcast in said storage medium.

2. The method for ensuring a storage time for digital broadcast of claim 1 further comprising the steps of:

if said calculated required capacity of the storage medium can be contained as the result of said determination, determining whether or not said empty area or freely limited area of the storage medium remains;

if said empty area or freely limited area remains, converting, in real time, said bit-rate of the broadcast into a larger one; and

storing said converted broadcast into said storage medium.

3. The method for ensuring a storage time for digital broadcast of claim 1 further comprising the step of:

if said calculated required capacity of the storage medium can be contained as the result of said determination, storing said broadcast in said storage medium without converting the bit-rate.

4. The method for ensuring a storage time for digital broadcast of claim 1, wherein said step of converting said bit-rate of the digitized broadcast into a smaller one is an operation of missing a part of said broadcast data.

5. The method for ensuring a storage time for digital broadcast of claim 1, wherein said step of converting said bit-rate of the digitized broadcast into a smaller one is an operation of returning said broadcast in a baseband and performing a compression processing again for the broadcast.

6. The method for ensuring a storage time for digital broadcast of claim 5, wherein said operation of returning said broadcast in a baseband and performing a compression processing again for the broadcast is performed by utilizing a system for compressing an analog broadcast, decoding the compressed digital data and then playing back the resultant data.

7. The method for ensuring a storage time for digital broadcast of claim 5, wherein said step of converting said bit-rate of the digitized broadcast into a smaller one is an operation of returning said broadcast in a baseband, then performing image resolution conversion or image frame rate conversion upon the broadcast and performing the compression processing again upon the resultant broadcast.

8. The method for ensuring a storage time for digital broadcast of claim 1, wherein said step of converting said bit-rate of the digitized broadcast into a smaller one is performed by selecting one from three kinds of operations, i.e., the operation of missing a part of the broadcast data, the operation of returning the broadcast in a baseband and performing a compression processing again upon the broadcast and the operation of returning the broadcast in a baseband, then performing image resolution conversion or image frame rate conversion upon the broadcast and performing the compression processing again upon the resultant broadcast.

9. The method for ensuring a storage time for digital broadcast of claim 1 further comprising the step of:

if said calculated required capacity of the storage medium cannot be contained, deleting a broadcast which has been already stored in said storage medium to ensure the required capacity of the storage medium.

10. The method for ensuring a storage time for digital broadcast of claim 1 further comprising the step of:

if said calculated required capacity of the storage medium cannot be contained, re-compressing said broadcast which has been already stored in the storage medium to ensure the required capacity of the storage medium.

11. The method for ensuring a storage time for digital broadcast of claim 10, wherein said step of re-compressing said broadcast which has been already stored in the storage medium is performed by the operation of missing a part of the stored broadcast data, the operation of returning the stored broadcast in a baseband and performing a compression processing again upon the broadcast or the operation of returning said stored broadcast in a baseband, then performing image resolution conversion or image frame rate conversion and performing a compression processing again upon the broadcast.

12. The method for ensuring a storage time for digital broadcast of claim 9, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast that a set period of time or longer has passed since its storage will be deleted.

13. The method for ensuring a storage time for digital broadcast of claim 9, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which has been decoded at least once since its storage will be deleted.

14. The method for ensuring a storage time for digital broadcast of claim 9, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which is stored in the storage medium and then copied in other storage medium will be deleted.

15. The method for ensuring a storage time for digital broadcast of claim 9, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which was stored at the earliest date will be deleted.

16. The method for ensuring a storage time for digital broadcast of claim 9, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast that a set period of time or longer has passed since its storage, a broadcast which has been decoded at least once since its storage, a broadcast which is stored in the storage medium and then copied in other storage medium or a broadcast which was stored at the earliest date will be deleted, and these broadcasts are selected in accordance with a predetermined priority.

17. The method for ensuring a storage time for digital broadcast of claim 10, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast that a set period of time or longer has passed since its storage will be re-compressed.

18. The method for ensuring a storage time for digital broadcast of claim 10, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which has been decoded at least once since its storage will be re-compressed.

19. The method for ensuring a storage time for digital broadcast of claim 10, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which is stored in the storage medium and then copied in other storage medium will be re-compressed.

20. The method for ensuring a storage time for digital broadcast of claim 10, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast which was stored at the earliest date will be re-compressed.

21. The method for ensuring a storage time for digital broadcast of claim 10, wherein when a plurality of already stored broadcasts exist in the storage medium, a broadcast that a set period of time or longer has passed since its storage, a broadcast which has been decoded at least once since its storage, a broadcast which is stored in the storage medium and then copied in other storage medium or a broadcast which was stored at the earliest date will be re-compressed, and these broadcasts are selected in accordance with a predetermined priority.

22. A device for ensuring a storage time for digital broadcast at the time of storing a digitized and then transmitted broadcast comprising:

a required capacity calculation circuit for monitoring a predetermined recording time of the broadcast and a bit-rate of the broadcast and calculating, in real time, a required capacity of the storage medium;

a determination circuit for determining whether or not the required capacity of the storage medium calculated in said required capacity calculation circuit can be contained within an empty or freely limited area in the storage medium; and

a bit-rate conversion circuit for, if said calculated required capacity of the storage medium cannot be contained as the result of said determination by said determination circuit, converting, in real time, said bit-rate of the broadcast into a smaller one and storing the converted broadcast in said storage medium.

23. The device for ensuring a storage time for digital broadcast of claim 22, wherein said determination circuit further determines, if said calculated required capacity of the storage medium can be contained, whether or not said empty or freely limited area of the storage medium remains, and said device further comprising:

a second bit-rate changing circuit for, if the empty or freely limited area remains as the result of said determination by said determination circuit, converting, in real time, said bit-rate of the broadcast into a larger one and storing the converted broadcast in said storage medium.

24. The device for ensuring a storage time for digital broadcast of claim 22, wherein said required capacity calculation circuit comprising:

a determination circuit for writing an inputted broadcast stream in a storage memory and determining said bit-rate of the broadcast on the basis of its storage time and storage amount.

25. The device for ensuring a storage time for digital broadcast of claim 22 further comprising:

a deletion circuit for, if said calculated required capacity of the storage medium cannot, be contained as the result of determination by said determination circuit, deleting a broadcast which has been already stored in the storage medium.

26. The device for ensuring a storage time for digital broadcast of claim 22 further comprising:

a re-compression circuit for, if said calculated required capacity of the storage medium cannot be contained as the result of determination by said determination circuit, re-compressing a broadcast which has been already stored in the storage medium.

27. The device for ensuring a storage time for digital broadcast of claim 22, wherein said required capacity calculation circuit, said determination circuit and said bit-rate conversion circuit are integrated onto a chip.