Method for transcoding MPEG encoded streams

• US 7,421,024 B2
• Filed: 06/30/2003
• Issued: 09/02/2008
• Est. Priority Date: 06/30/2003
• Status: Active Grant

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: Intel Corporation
• Inventors: Castillo, Michael J.
• Primary Examiner(s): VO, DON NGUYEN
• Application Number:
  US10/611,452
• Publication Number:
  US 20040264803A1
• Time in Patent Office: 1,891 Days
• Field of Search: 375/240, 375/240.12, 375/240.01, 375/240.25, 375/240.18, 375/240.26, 382/243, 382/250, 725/100, 341/61
• US Class Current: 375/240.18
• CPC Class Codes: H04N 21/4122 additional display device, e.g. video projector digital output for controlling a plurality of local displays G06F3/1423
• CPC Class Codes: H04N 21/43637 involving a wireless protocol, e.g. Bluetooth, RF or wireless LAN [IEEE 802.11] arrangements for wireless networking or broadcasting of information in indoor or near-field type systems H04B10/114
• CPC Class Codes: H04N 21/4402 involving reformatting operations of video signals for household redistribution, storage or real-time display details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4408 involving video stream encryption, e.g. re-encrypting a decrypted video stream for redistribution in a home network
• CPC Class Codes: H04N 21/4621 Controlling the complexity of the content stream or additional data, e.g. lowering the resolution or bit-rate of the video stream for a mobile client with a small screen arrangements for using the results of monitoring on user's side in broadcast systems H04H60/65; flow control in packet networks H04L47/10

Abstract

A system and method of transcoding video data for distribution over a variety of media. A digital data stream is decoded and optionals down sampled to reduce the bit rate of the original stream. The decoded stream is further encoded to further reduce the bit rate of the data stream to be consistent with the reliable delivery capabilities of the media over which the data stream is to be transmitted and/or the display on which display is to occur.

Claims

1. A method comprising:

decoding a digital data stream received at a video decoder into data including decompressed video data;

passing a decoded data stream to an encoder;

dynamically adjusting an aggressiveness of down sampling of the data stream prior to passing the data stream, wherein down sampling is based at least on constraints imposed by storage resources; and

encoding the decoded data stream at a bit rate below a bit rate of the digital data stream to form a lower bit rate data stream.

2. The method of claim 1 further comprising:

storing data corresponding to the lower bit rate data stream in a non-volatile storage medium.

3. The method of claim 1 further comprising:

encrypting the lower bit rate data stream; and

busing the encrypted lower bit rate data stream to a distribution interface.

4. The method of claim 1 comprising:

sending the digital data stream to a display device if the display device is local to the video decoder; and

sending the lower bit rate data stream to a display device if the display device is remote from the video decoder.

5. The method of claim 1 further comprising:

wirelessly transmitting the lower bit rate data stream to a display device.

6. The method of claim 1 wherein the encoding comprises:

compressing the decoded data stream.

7. The method of claim 1 wherein the dynamic adjustment of down sampling is accomplished including by a look up table.

8. The method of claim 7 wherein look-up is based at least on constraints imposed by expected transport media, storage resources, or target display.

9. The method of claim 1 wherein the down sampling comprises down sampling based at least on a desired bit rate to allow longer recording times by reducing a non-volatile storage required for each unit of time of the down sampled data stream.

10. The method of claim 9 wherein encoding comprises further compressing the down sampled data stream to the desired bit rate, the desired bit rate being based at least on allowing longer recording times.

11. An apparatus comprising:

a video decoder having an output to output a decoded data stream including decompressed video data, and having a digital input interface;

an encoder coupled to the video decoder to encode a decoded data stream received from the video decoder;

down sampling logic to dynamically adjust the aggressiveness of down sampling of the data stream, wherein down sampling is based at least on constraints imposed by storage resources; and

a non-volatile storage unit coupled to the video decoder.

12. The apparatus of claim 11 wherein the video decoder comprises:

an encryption engine; and

a decryption engine.

13. The apparatus of claim 11 wherein the encoder comprises:

a compression engine.

14. The apparatus of claim 13 wherein the compression engine performs motion picture experts group (MPEG) encoding.

15. The apparatus of claim 11 further comprising:

a local area network interface.

16. The apparatus of claim 11 further comprising:

a wireless network interface.

17. The apparatus of claim 11 further comprising:

a host processor coupled to the video decoder.

18. A system comprising:

a video decoder including an output to output a decoded data stream having decompressed video data, and including a down sampler wherein the aggressiveness of down sampling is dynamically adjusted, wherein down sampling is based at least on constraints imposed by storage resources;

an encoder coupled to the video decoder to encode a video stream at a bit rate below a bit rate of a source stream;

a wireless interface operably coupled to the video decoder to transmit the video stream at the bit rate below the bit rate of the source stream; and

a display to receive and display the video stream.

19. The system of claim 18 further comprising:

a non-volatile storage unit coupled to the video decoder.

20. The system of claim 18 further comprising:

a local interface operably coupled to the video decoder to transmit the source stream at a full bit rate; and

a display coupled to the local interface.

21. An apparatus comprising:

means for decoding an incoming video stream into a decoded video stream including decoded video data;

means for down sampling the decoded video stream wherein the aggressiveness of down sampling is dynamically adjusted, wherein down sampling is based at least on constraints imposed by storage resources; and

means for encoding the decoded video stream into a lower bit rate video stream.

22. The apparatus of claim 21 further comprising:

means for storing the lower bit rate video stream.

23. The apparatus of claim 21 further comprising:

means of selecting the lower bit rate based on a transmission medium to be used.

24. A computer readable storage media containing executable computer program instructions which when executed cause a digital processing system to perform a method comprising:

decoding a digital data stream received at a video decoder into data including decompressed video data;

dynamically adjusting the aggressiveness of down sampling of decoded data stream, wherein down sampling is based at least on constraints imposed by storage resources; and

encoding the decoded data stream at a bit rate below a bit rate of the digital data stream to form a lower bit rate data stream.

25. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

down sampling the data stream prior to passing the decoded data stream.

26. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

storing data corresponding to the lower bit rate data stream in a non-volatile storage medium.

27. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

encrypting the lower bit rate data stream; and

busing the encrypted lower bit rate data stream to a distribution interface.

28. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

sending the digital data stream to a display device if the display device is local to the video decoder; and

sending the lower bit rate data stream to a display device if the display device is remote from the video decoder.

29. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

wirelessly transmitting the lower bit rate data stream to a display device.

30. The computer readable storage media of claim 24 which when executed cause a digital processing system to perform a method further comprising:

compressing the decoded data stream.