Method and apparatus for controlling encoding of a digital video signal according to monitored parameters of a radio frequency communication signal

• US 6,611,674 B1
• Filed: 08/06/1999
• Issued: 08/26/2003
• Est. Priority Date: 08/07/1998
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Jokimies, Matti, Luomi, Marko, Jarvinen, Petri, Lunden, Vesa, Hakaste, Markus
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): PEREZ GUTIERREZ, RAFAEL
• Application Number:
  US09/370,661
• Time in Patent Office: 1,481 Days
• Field of Search: 375/240.07, 375/240.02, 375/240.01, 375/240.24, 375/240.27, 725/124, 725/62, 725/63, 725/67, 725/68, 725/118, 725/121, 725/123, 348/180, 348/193, 348/192, 455/67.1, 455/69, 455/67.3, 455/522, 455/226.1, 455/226.2, 455/226.3, 455/115, 455/68, 455/126, 370/465, 714/746, 714/752, 714/774
• US Class Current: 455/69
• CPC Class Codes: H04L 1/0014 by adapting the source coding
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/156 Availability of hardware or computational resources, e.g. encoding based on power-saving criteria
• CPC Class Codes: H04N 19/164 Feedback from the receiver or from the transmission channel
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 7/147 Communication arrangements, e.g. identifying the communication as a video-communication, intermediate storage of the signals selecting H04Q

Abstract

Method and apparatus for controlling the operation of a video codec designed for encoding video data suitable for radio transmission between a network and a mobile station. The invention is particularly applicable where the transmission errors are unpredictable, and entails monitoring one or more parameters of the received or transmitted signal and providing a feedback signal based on the monitored signal, the feedback signal controlling the encoding parameters in the algorithm of the video codec.

Claims

1. A system for controlling the source coding of a digital video signal by a video encoder, the digital video signal being encoded by the video encoder in accordance with predetermined encoding parameters so as to provide an encoded video data signal for transmission by means of a radio frequency communication signal by a first radio communication device to a second radio communication device, the radio frequency communication signal being received at the second radio communication device, the system comprising:

means for monitoring at least one parameter indicative of a property of the radio frequency communication signal received at the second radio communication device;

means for forming a feed back signal responsive to the at least one monitored parameter for controlling at least one of the predetermined encoding parameters used by the video encoder in the source coding of the digital video signal;

means for transmitting the feedback signal from the second radio communication device to the first radio communication device;

means for receiving the feedback signal at the first radio communication device;

means for providing the feedback signal received at the first radio communication device to the video encoder; and

means for modifying at least one of the pre-determined encoding parameters used by the video encoder in the source coding of the digital video signal.

2. A system according to claim 1, further comprising a third radio communication device, wherein the video encoder is located in connection with the third radio communication device, and wherein the first radio communication device is a radio communication network, and the second radio communication device and the third radio communication device are a portable radio communication apparatus or a radio card for use in connection with a personal computer.

3. A system according to claim 2, wherein the third radio communication device comprises means for transmitting a digital video signal encoded by the video encoder as a radio frequency communication signal to the first radio communication device and the first radio communication device comprises means for transmitting the digital video signal encoded by the video encoder as a radio frequency communication signal to the second radio communication device.

4. A system according to claim 3, wherein the first radio communication device comprises means for transmitting the feedback signal responsive to the at least one monitored parameter transmitted from the second radio communication device to the first radio communication device further from the first radio communication device to the third radio communication device.

5. A system according to claim 4, wherein transmission of the feedback signal responsive to the at least one monitored parameter from the second radio communication device to the first radio communication device and further from the first radio communication device to the third radio communication device is arranged to be performed by an end-to-end control protocol.

6. A system according to claim 5, wherein the end-to-end control protocol is an H.245 control protocol.

7. A system according to claim 1, further comprising means for measuring a signal quality of the radio frequency communication signal received at the second radio communication device as the at least one parameter indicative of a property of the radio frequency communication signal.

8. A system according to claim 1, further comprising means for measuring a signal strength of the radio frequency communication signal received at the second radio communication device as the at least one parameter indicative of a property of the radio frequency communication signal.

9. A system according to claim 1, wherein the second communication device is a radio communication network, and the first radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

10. A system according to claim 1, wherein the first radio communication device is a radio communication network and the second radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

11. A system according to claim 1 wherein the at least one of the predetermined encoding parameters used by the video encoder in the source coding is arranged to control the frequency of intra-refresh data in the encoded video data.

12. A system according to claim 1 wherein the at least one of the predetermined encoding parameters used by the video encoder in the source coding is arranged to control the frequency of start codes in the encoded video data.

13. A system according to claim 1, wherein the video encoder is remote from the first radio communication device.

14. A system according to claim 13, wherein the video encoder is located in a personal computer in connection with the first radio communication device.

15. A system according to claim 1, wherein the video encoder is located in the first radio communication device.

16. A method of controlling the source coding of a digital video signal by a video encoder, in which the digital video signal is encoded by the video encoder in accordance with predetermined encoding parameters so as to provide an encoded video data signal for transmission by means of a radio frequency communication signal by a first radio communication device to a second radio communication device, the radio frequency communication signal being received at the second radio communication device, the method comprising the steps of:

monitoring at least one parameter indicative of a property of the radio frequency communication signal received at the second radio communication device;

responsive to the at least one monitored parameter, forming a feedback signal for controlling at least one of the predetermined encoding parameters used by the video encoder in the source coding of the digital video signal;

transmitting the feedback signal from the second radio communication device to the first radio communication device;

receiving the feedback signal at the first radio communication device;

providing the feedback signal received at the first radio communication device to the video encoder; and

modifying at least one of the predetermined encoding parameters used by the video encoder in the source coding of the digital video signal.

17. A method according to claim 16, wherein the video encoder is located in connection with a third radio communication device, the first radio communication device is a radio communication network, and the second radio communication device and the third radio communication device are a portable radio communication apparatus or a radio card for use in connection with a personal computer.

18. A method according to claim 17, wherein the digital video signal is encoded by the video encoder and is transmitted as a radio frequency communication signal from the third radio communication device to the first radio communication device and further from the first radio communication device to the second radio communication device.

19. A method, according to claim 18, wherein the feedback signal responsive to the at least one monitored parameter transmitted from the second radio communication device to the first radio communication device is further transmitted from the first radio communication device to the third radio communication device.

20. A method according to claim 19, wherein the transmission of the feedback signal responsive to the at least one monitored parameter from the second radio communication device to the first radio communication device and further from the first radio communication device to the third radio communication device is performed by an end-to-end control protocol.

21. A method according to claim 20, wherein the end-to-end control protocol is an H.245 control protocol.

22. A method according to claim 16, wherein the second communication device is a radio communication network, and the first radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

23. A method according to claim 16, wherein the first radio communication device is a radio communication network and the second radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

24. A method according to claim 16, wherein the at least one parameter indicative of a property of the radio frequency communication signal monitored at the second radio communication device is a measure of received signal quality.

25. A method according to claim 16, wherein the at least one parameter indicative of a property of the radio frequency communication signal monitored at the second radio communication device is a measure of received signal strength.

26. A method according to claim 16, wherein the at least one of the predetermined encoding parameters used by the video encoder in the source coding controls the frequency of intra-refresh data in the encoded video data.

27. A method according to claim 16, wherein the at least one of the predetermined encoding parameters used by the video encoder in the source coding controls the frequency of start codes in the encoded video data.

28. A method according to claim 16, wherein the video encoder is remote from the first radio communication device.

29. A method according to claim 28, wherein the video encoder is located in a personal computer in connection with the first radio communication device.

30. A method according to claim 16, wherein the video encoder is located in the first radio communication device.

31. An apparatus for controlling the source coding of a digital video signal by a video encoder, the digital video signal being encoded by the video encoder in accordance with predetermined encoding parameters so as to provide an encoded video data signal for transmission by means of a radio frequency communication signal by a first radio communication device to a second radio communication device, the radio frequency communication signal being received at the second radio communication device, wherein the apparatus is located in the second radio communication device, the apparatus comprising:

means for monitoring at least one parameter indicative of a property of the radio frequency communication signal received at the second radio communication device; and

means for forming a feedback signal responsive to the at least one monitored parameter for controlling at least one of the predetermined encoding parameters used by the video encoder in the source coding of the digital video signal.

32. An apparatus according to claim 31, further comprising means for measuring a signal quality of the radio frequency communication signal received at the second radio communication device as the at least one parameter indicative of a property of the radio frequency communication signal.

33. An apparatus according to claim 31, further comprising means for measuring a signal strength of the radio frequency communication signal received at the second radio communication device as the at least one parameter indicative of a property of the radio frequency communication signal.

34. A system for controlling encoding of a digital video signal, the digital video signal being encoded by a video encoder and transmitted by means of a radio frequency communication signal by a first radio communication device, the radio frequency communication signal being received by a second radio communication device, the system comprising:

means for monitoring at least one parameter indicative of a property of the radio frequency communication signal at the first radio communication device;

means for forming a feedback signal responsive to the at least one monitored parameter indicative of a property of the radio frequency communication signal for controlling at least one encoding parameter of the video encoder; and

means for providing the feedback signal to the video encoder to control the encoding of the digital video signal.

35. A system according to claim 34, wherein the means for monitoring at least one parameter indicative of a property of the radio frequency signal at the first radio communication device comprises means responsive to a power control command received at the first radio communication device.

36. A system according to claim 34, wherein the means for monitoring at least one parameter indicative of a property of the radio frequency signal at the first radio communication device comprises means for measuring a transmission power of the radio frequency communication signal.

37. A system according to claim 34, wherein the second communication device is a radio communication network, and the first radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

38. A system according to claim 34 wherein the at least one encoding parameter of the video encoder is arranged to control the frequency of intra-refresh data in the encoded video data.

39. A system according to claim 34 wherein the at least one encoding parameter of the video encoder is arranged to control the frequency of start codes in the encoded video data.

40. A method of controlling encoding of a digital video signal, in which the digital video signal is encoded by a video encoder and transmitted by means of a radio frequency communication signal by a first radio communication device, the radio frequency communication signal being received by a second radio communication device, the method comprising the steps of:

monitoring at least one parameter indicative of a property of the radio frequency communication signal at the first radio communication device;

responsive to the at least one monitored parameter, forming a feedback signal for controlling at least one encoding parameter of the video encoder; and

providing the feedback signal to the video encoder to control the encoding of the digital video signal.

41. A method according to claim 40, wherein the second communication device is a radio communication network, and the first radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

42. A method according to claim 40, wherein the first radio communication device is a radio communication network and the second radio communication device is a portable radio communication apparatus or a radio card for use in connection with a personal computer.

43. A method according to claim 40, wherein the at least one parameter indicative of a property of the radio frequency communication signal monitored at the first radio communication device is a power control command received at the first radio communication device.

44. A method according to claim 40, wherein the at least one parameter indicative of a property of the radio frequency communication signal monitored at the first radio communication device is a measure of transmitted signal power.

45. A method according to claim 40, wherein the at least one encoding parameter of the video encoder controls the frequency of intra-refresh data in the encoded video data.

46. A method according to claim 40, wherein the at least one encoding parameter of the video encoder controls the frequency of start codes in the encoded video data.

47. A method according to claim 40, wherein the video encoder is remote from the first radio communication device.

48. A method according to claim 47, wherein the video encoder is located in a personal computer in connection with the first radio communication device.

49. A method according to claim 40, wherein the video encoder is located in the first radio communication device.

50. An apparatus for controlling encoding of a digital video signal, the digital video signal being encoded by a video encoder and transmitted by means of a radio frequency communication signal by a first radio communication device, the radio frequency communication signal being received by a second radio communication device, wherein the apparatus is located in the first radio communication device, the apparatus comprising:

means for monitoring at least one parameter indicative of a property of the radio frequency communication signal at the first radio communication device; and

means for forming a feedback signal responsive to the at least one monitored parameter indicative of a property of the radio communication signal for controlling at least one encoding parameter of the video encoder.

51. An apparatus according to claim 50, wherein the means for monitoring at least one parameter indicative of a property of the radio frequency signal at the first radio communication device comprises means responsive to a power control command received at the first radio communication device.

52. An apparatus according to claim 50, wherein the means for monitoring at least one parameter indicative of a property of the radio frequency signal at the first radio communication device comprises means for measuring a transmission power of the radio frequency communication signal.

53. A digital video encoder comprising encoder means for source coding of a digital video signal, the digital video signal being encoded by the encoder means in accordance with predetermined encoding parameters so as to provide an encoded video data signal for transmission by means of a radio communication signal by a first radio communication device to a second radio communication device,

the encoder means being operable to respond to feedback signals based on at least one monitored parameter indicative of a property of the radio frequency communication signal and to modify at least one of the pre-determined encoding parameters used by the video encoder in the source coding of the digital video signal.