Data communication system, data transmission apparatus, data receiving apparatus, data communication method, data transmission method, received-data processing method, and computer program

• US 20030118107A1
• Filed: 11/12/2002
• Published: 06/26/2003
• Est. Priority Date: 11/12/2001
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Itakura, Eisaburo, Fukuhara, Takahiro, Ichino, Yasuhiko
• Granted Patent: US 7,385,921 B2
• Time in Patent Office: Days
• US Class Current: 375/240.19
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/234354 by altering signal-to-noise ratio parameters, e.g. requantization
• CPC Class Codes: H04N 21/234363 by altering the spatial resolution, e.g. for clients with a lower screen resolution
• CPC Class Codes: H04N 21/23614 Multiplexing of additional data and video streams arrangements for simultaneous broadcast of plural pieces of information H04H20/28
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/6375 for requesting retransmission , e.g. of data packets lost or corrupted during transmission from serverARQ protocols H04L1/18; implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP] H04L69/16
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/64322 IP
• CPC Class Codes: H04N 21/6582 Data stored in the client, e.g. viewing habits, hardware capabilities, credit card number arrangements where receivers interact with the broadcast H04H20/38

Abstract

A system allows data transfer in which the most appropriate packet processing is executed according to the performance of a terminal. A data transmission side stores scalable-encoded data in a packet as a payload, assigns priority-level information corresponding to a layer level of the encoded data stored in the packet to a packet header, and transmits the packet. A data receiving side performs processing by referring to the priority-level information. A level of priority dependent on an application is specified in an RTP payload header according to the degree of importance of scalable-encoded data, and a level of priority is further specified in an IP header. The most appropriate packet processing based on the performance of a terminal is allowed. Re-transmission control based on the layer level of encoded data is also allowed.

Claims

1. A data communication system, comprising:

a data transmission apparatus which includes encoding parts for applying scalable-encoding processing by using wavelet transform to an image signal, and packet generation parts for generating a packet which stores scalable-encoded data generated by the encoding parts and for specifying priority-level information corresponding to a layer of the scalable-encoded data of the image signal, stored in the generated packet; and

a data receiving apparatus which includes decoding parts for applying decoding processing to data stored in a packet to which the information of a level of priority equal to or larger than a value specified according to the a processing performance of the data receiving apparatus is assigned.

2. A data communication system as claimed in claim 1, wherein the data receiving apparatus further includes packet-priority-level-information determination parts for determining whether a packet has the information of a level of priority equal to or larger than the value specified according to the processing performance of the data receiving apparatus, and the decoding parts apply the decoding processing to data stored in a packet selected by the packet-priority-level-information determination parts.

3. A data communication system as claimed in claim 1, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header.

4. A data communication system as claimed in claim 1, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an IP header.

5. A data communication system as claimed in claim 1, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header and an IP header.

6. A data communication system as claimed in claim 1, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet, according to a priority-level setting map in which the layer of the scalable-encoded data is associated with a level of priority.

7. A data communication system as claimed in claim 1, wherein the data transmission apparatus further includes a structure for receiving receiving-terminal information from the data receiving apparatus, and the packet generation parts dynamically change the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to the receiving-terminal information.

8. A data communication system as claimed in claim 1, wherein the data transmission apparatus dynamically changes the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to a network condition.

9. A data communication system as claimed in claim 1, wherein the encoding parts of the data transmission apparatus apply the scalable-encoding processing by using the wavelet transform to the image signal, and generate encoded data having different spatial resolutions generated by the wavelet transform, and the packet generation parts specify priority-level information corresponding to layers of the spatial resolutions of the encoded data having the different spatial resolutions, as additional information of the generated packet.

10. A data communication system as claimed in claim 1, wherein the encoding parts of the data transmission apparatus generate scalable-encoded data by progressive encoding processing, and the packet generation parts specify priority-level information corresponding to a layer specified for a progressive order of the scalable-encoded data generated by applying the progressive encoding processing to the image signal and stored in the generated packet, as additional information of the generated packet.

11. A data communication system as claimed in claim 1, wherein the encoding parts of the data transmission apparatus generate scalable-encoded data by progressive encoding processing in which different spatial resolutions are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each spatial resolution of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

12. A data communication system as claimed in claim 1, wherein the encoding parts of the data transmission apparatus generate scalable-encoded data by progressive encoding processing in which different SNRs are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each SNR of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

13. A data communication system as claimed in claim 1, wherein the encoding parts of the data transmission apparatus generate scalable-encoded data by progressive encoding processing in which different color components are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each color component of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

14. A data communication system as claimed in claim 1, wherein the data transmission apparatus further includes a re-transmission control structure for, in response to a packet re-transmission request sent from the data receiving apparatus, determining the levels of priority assigned to packets for which the re-transmission request has been sent, for determining whether re-transmission is to be performed according to the determined levels of priority, and for re-transmitting packets having higher levels of priority earlier.

15. A data transmission apparatus for storing image data in a packet and for transmitting the packet, comprising:

encoding parts for applying scalable-encoding processing by using wavelet transform to an image signal; and

packet generation parts for generating a packet which stores scalable-encoded data generated by the encoding parts and for specifying priority-level information corresponding to a layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

16. A data transmission apparatus as claimed in claim 15, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header.

17. A data transmission apparatus as claimed in claim 15, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an IP header.

18. A data transmission apparatus as claimed in claim 15, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header and an IP header.

19. A data transmission apparatus as claimed in claim 15, wherein the packet generation parts specify the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet, according to a priority-level setting map in which the layer of the scalable-encoded data is associated with a level of priority.

20. A data transmission apparatus as claimed in claim 15, wherein the data transmission apparatus further includes a structure for receiving receiving-terminal information from the data receiving apparatus, and the packet generation parts dynamically change the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to the receiving-terminal information.

21. A data transmission apparatus as claimed in claim 15, wherein the data transmission apparatus dynamically changes the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to a network condition.

22. A data transmission apparatus as claimed in claim 15, wherein the encoding parts apply the scalable-encoding processing by using the wavelet transform to the image signal, and generate encoded data having different spatial resolutions generated by the wavelet transform, and the packet generation parts specify priority-level information corresponding to layers of the spatial resolutions of the encoded data having the different spatial resolutions, as additional information of the generated packet.

23. A data transmission apparatus as claimed in claim 15, wherein the encoding parts generate scalable-encoded data by progressive encoding processing, and the packet generation parts specify priority-level information corresponding to a layer specified for a progressive order of the scalable-encoded data generated by applying the progressive encoding processing to the image signal and stored in the generated packet, as additional information of the generated packet.

24. A data transmission apparatus as claimed in claim 15, wherein the encoding parts generate scalable-encoded data by progressive encoding processing in which different spatial resolutions are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each spatial resolution of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

25. A data transmission apparatus as claimed in claim 15, wherein the encoding parts generate scalable-encoded data by progressive encoding processing in which different SNRs are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each SNR of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

26. A data transmission apparatus as claimed in claim 15, wherein the encoding parts generate scalable-encoded data by progressive encoding processing in which different color components are specified in a progressive order, and the packet generation parts specify priority-level information corresponding to a layer specified for each color component of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

27. A data transmission apparatus as claimed in claim 15, wherein the data transmission apparatus further includes a re-transmission control structure for, in response to a packet re-transmission request sent from the data receiving apparatus, determining the levels of priority assigned to packets for which the re-transmission request has been sent, for determining whether re-transmission is to be performed according to the determined levels of priority, and for re-transmitting packets having higher levels of priority earlier.

28. A data receiving apparatus for receiving packets which store encoded data, comprising:

receiving parts for receiving packets which store data scalable-encoded by wavelet transform;

packet-priority-level-information determination parts for determining whether the packets have the information of a level of priority equal to or larger than a value specified according to a processing performance of the n data receiving apparatus; and

decoding parts for decoding data stored in packets selected by the packetpriority-level-information determination parts.

29. A data receiving apparatus as claimed in claim 28, wherein the packetpriority-level-information determination parts include IP packet filtering parts for determining a level of priority assigned to an IP header of a received packet, and RTP-packet-header scanning parts for determining a level of priority assigned to an RTP header of the received packet.

30. A data communication method for a data communication system including a data transmission apparatus and a data receiving apparatus, the method comprising the steps of:

applying scalable-encoding processing by using wavelet transform to an image signal;

generating a packet which stores scalable-encoded data generated in the encoding step and specifying priority-level information corresponding to a layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet, both steps being executed in the data transmission apparatus; and

decoding data stored in a packet to which the information of a level of priority equal to or larger than a value specified according to a processing performance of the data receiving apparatus is assigned, the decoding step being executed in the data receiving apparatus.

31. A data communication method as claimed in claim 30, the method further comprising the step of:

determining whether a packet has the information of a level of priority equal to or larger than the value specified according to the processing performance of the data receiving apparatus, the step being executed by the data receiving apparatus, wherein the decoding step decodes data stored in a packet selected by the determining step.

32. A data communication method as claimed in claim 30, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header.

33. A data communication method as claimed in claim 30, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an IP header.

34. A data communication method as claimed in claim 30, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header and an IP header.

35. A data communication method as claimed in claim 30, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet, according to a priority-level setting map in which the layer of the scalable-encoded data is associated with a level of priority.

36. A data communication method as claimed in claim 30, the method further comprising the step of receiving receiving-terminal information from the data receiving apparatus, the step being executed by the data transmission apparatus, wherein the packet generation step includes a step of dynamically changing the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to the receiving-terminal information.

37. A data communication method as claim in claim 30, the method further comprising the step of dynamically changing the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to a network condition, the step being executed by the data transmission apparatus.

38. A data communication method as claimed in claim 30, wherein the encoding step executed in the data transmission apparatus includes a step of applying the scalable-encoding processing by using the wavelet transform to the image signal, and of generating encoded data having different spatial resolutions generated by the wavelet transform, and the packet generation step includes a step of specifying priority-level information corresponding to layers of the spatial resolutions of the encoded data having the different spatial resolutions, as additional information of the generated packet.

39. A data communication method as claimed in claim 30, wherein the encoding step executed in the data transmission apparatus includes a step of generating scalable-encoded data by progressive encoding processing, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for a progressive order of the scalable-encoded data generated by applying the progressive encoding processing to the image signal and stored in the generated packet, as additional information of the generated packet.

40. A data communication method as claimed in claim 30, wherein the encoding step executed in the data transmission apparatus includes a step of generating scalable-encoded data by progressive encoding processing in which different spatial resolutions are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each spatial resolution of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

41. A data communication method as claim in claim 30, wherein the encoding step executed in the data transmission apparatus includes a step of generating scalable-encoded data by progressive encoding processing in which different SNRs are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each SNR of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

42. A data communication method as claimed in claim 30, wherein the encoding step executed in the data transmission apparatus includes a step of generating scalable-encoded data by progressive encoding processing in which different color components are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each color component of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

43. A data communication method as claimed in claim 30, the method further comprising the step of, in response to a packet re-transmission request sent from the data receiving apparatus, determining the levels of priority assigned to packets for which the re-transmission request has been sent, determining whether re-transmission is to be performed according to the determined levels of priority, and re-transmitting packets having higher levels of priority earlier, the steps being executed by the data transmission apparatus.

44. A data transmission method for storing image data in a packet and for transmitting the packet, the method comprising the steps of:

applying scalable-encoding processing by using wavelet transform to an image signal; and

generating a packet which stores scalable-encoded data generated in the encoding step and of specifying priority-level information corresponding to a layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

45. A data transmission method as claimed in claim 44, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header.

46. A data transmission method as claimed in claim 44, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an IP header.

47. A data transmission method as claimed in claim 44, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, in an RTP header and an IP header.

48. A data transmission method as claimed in claim 44, wherein the packet generation step includes a step of specifying the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet, according to a priority-level setting map in which the layer of the scalable-encoded data is associated with a level of priority.

49. A data transmission method as claimed in claim 44, the method further comprising the step of receiving receiving-terminal information from the data receiving apparatus, the step being executed by the data transmission apparatus, wherein the packet generation step includes a step of dynamically changing the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to the receiving-terminal information.

50. A data transmission method as claimed in claim 44, the method further comprising the step of dynamically changing the priority-level information corresponding to the layer of the scalable-encoded data of the image signal, stored in the packet, according to a network condition, the step being executed by the data transmission apparatus.

51. A data transmission method as claimed in claim 44, wherein the encoding step includes a step of applying the scalable-encoding processing by using the wavelet transform to the image signal, and a step of generating encoded data having different spatial resolutions generated by the wavelet transform, and the packet generation step includes a step of specifying priority-level information corresponding to layers of the spatial resolutions of the encoded data having the different spatial resolutions, as additional information of the generated packet.

52. A data transmission method as claimed in claim 44, wherein the encoding step includes a step of generating scalable-encoded data by progressive encoding processing, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for a progressive order of the scalable-encoded data generated by applying the progressive encoding processing to the image signal and stored in the generated packet, as additional information of the generated packet.

53. A data transmission method as claimed in claim 44, wherein the encoding step includes a step a step of generating scalable-encoded data by progressive encoding processing in which different spatial resolutions are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each spatial resolution of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

54. A data transmission method as claimed in claim 44, wherein the encoding step includes a step of generating scalable-encoded data by progressive encoding processing in which different SNRs are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each SNR of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

55. A data transmission method as claimed in claim 44, wherein the encoding step includes a step of generating scalable-encoded data by progressive encoding processing in which different color components are specified in a progressive order, and the packet generation step includes a step of specifying priority-level information corresponding to a layer specified for each color component of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.

56. A data transmission method as claimed in claim 44, the method further comprising the steps of, in response to a packet re-transmission request sent from the data receiving apparatus, determining the levels of priority assigned to packets for which the re-transmission request has been sent, determining whether re-transmission is to be performed according to the determined levels of priority, and re-transmitting packets having higher levels of priority earlier, the steps being executed by the data transmission apparatus.

57. A received-data processing method for receiving packets which store encoded data and for executing data processing, the method comprising the steps of:

receiving packets which store data scalable-encoded by wavelet transform;

determining whether the packets have information of a level of priority equal to or larger than a value specified according to a processing performance of the data receiving apparatus; and

decoding data stored in packets selected in the determining step.

58. A received-data processing method as claimed in claim 57, wherein the determining step includes an IP-packet filtering step of determining a level of priority assigned to an IP header of each received packet, and an RTP-packet-header scanning step of determining a level of priority assigned to an RTP header of the received packet.

59. A computer program for executing processing for storing image data in a packet and for sending the packet, comprising:

an encoding step of applying scalable-encoding processing by using wavelet transform to an image signal; and

a packet generation step of generating a packet which stores scalable-encoded data generated in the encoding step and of specifying priority-level information corresponding to a layer of the scalable-encoded data of the image signal, stored in the generated packet, as additional information of the generated packet.