Systems and methods for channel switching
Techniques for video encoding and decoding channel switch frames (CSF) to enable acquisition and re/synchronization of the video stream while preserving compression efficiency is provided. Systems and methods to process multimedia data enabling channel switching are presented. The systems generate a CSF with one or more network adaptation layer (NAL) units as a random access point (RAP) frame. Back-to-back frames are transmitted which include the CSF and a non-RAP frame, each having the same frame ID number.
1. A device comprising:
a processor operative to generate a channel switch frame (CSF) from one or more network abstraction layer (NAL) units to enable random access points in a coded bitstream, wherein at least one of the NAL units comprises an Instantaneous Decoding Refresh (IDR) NAL unit having a non-zero frame identification number equal to a frame number of a corresponding P-slice.
2. The device of claim 1 , wherein the IDR NAL unit has a non-zero picture order count (POC) number.
3. The device of claim 1 , wherein the processor is operative to generate the CSF with at least two additional NAL units, the at least two additional NAL units comprising a sequence parameter set (SPS) NAL unit and a picture parameter set (PPS) NAL unit.
4. The device of claim 1 , wherein the CSF includes an I-frame NAL unit.
5. The device of claim 1 , further comprising a transmitter to broadcast the CSF as a random access point (RAP) frame.
6. The device of claim 1 , wherein the CSF is operative to cause switching from one channel to another channel or to facilitate error recovery.
7. An integrated circuit comprising:
a processor operative to generate a channel switch frame (CSF) from one or more network abstraction layer (NAL) units to enable random access points in a coded bitstream, wherein at least one of the NAL units comprises a low-quality Instantaneous Decoding Refresh (IDR) NAL unit having a non-zero frame identification number equal to a frame number of a corresponding P-slice.
8. The integrated circuit of claim 7 , wherein the IDR NAL unit has a non-zero picture order count (POC) number.
9. The integrated circuit of claim 7 , wherein the processor is operative to generate the CSF with at least two additional NAL units, the at least two additional NAL units comprising a sequence parameter set (SPS) NAL unit and a picture parameter set (PPS) NAL unit.
10. The integrated circuit of claim 7 , wherein the CSF includes an I-frame NAL unit.
11. The integrated circuit of claim 7 , further comprising a transmitter to broadcast the CSF as a random access point (RAP) frame.
12. The integrated circuit of claim 7 , wherein the CSF is operative to cause switching from one channel to another channel or to facilitate error recovery.
13. A computer program product including a non-transitory computer readable medium having instructions for causing a computer to:
generate a channel switch frame (CSF) from one or more network abstraction layer (NAL) units to enable random access points in a coded bitstream to cause switching from one channel to another channel or to facilitate error recovery, wherein at least one of the NAL units comprises a low-quality Instantaneous Decoding Refresh (IDR) NAL unit having a non-zero frame identification number equal to a frame number of a corresponding P-slice.
14. The computer program product of claim 13 , wherein the IDR NAL unit has a non-zero picture order count (POC) number.
15. The computer program product of claim 13 , wherein the instructions to generate the CSF includes instructions to generate the CSF with at least two additional NAL units, the at least two additional NAL units comprising a sequence parameter set (SPS) NAL unit and a picture parameter set (PPS) NAL unit.
16. The computer program product of claim 13 , wherein the instructions to generate the CSF includes instructions to generate an I-frame NAL unit.
17. A device comprising:
a processor operative to decode one or more of back-to-back video media frames of a block of consecutive video media frames, each with a same frame identification (ID) number that identifies a relative decode order of the corresponding frame, with a first video media frame of the back-to-back video media frames being a random access point (RAP) frame and a second video media frame of the back-to-back video media frames being a non-RAP frame.
18. The device of claim 17 , wherein the processor is operative to decode only one of the back-to-back frames.
19. The device of claim 17 , wherein the processor is operative to decode the RAP frame and drop frames in output order before the RAP frame.
20. The device of claim 19 , wherein the processor is operative to decode the RAP frame by decoding a channel switch frame comprising one or more network abstraction layer (NAL) units.
21. A computer program product including a non-transitory computer readable medium having instructions for causing a computer to:
decode one or more of back-to-back video media frames of a block of consecutive video media frames, each with a same frame identification (ID) number that identifies a relative decode order of the corresponding frame, with a first video media frame of the back-to-back video media frames being a random access point (RAP) frame and a second video media frame of the back-to-back video media frames being a non-RAP frame.
22. The computer program product of claim 21 , wherein the instructions to decode include instructions to decode only one of the back-to-back frames.
23. The computer program product of claim 21 , wherein the instructions to decode include instructions to decode the RAP frame and drop frames in output order before the RAP frame.
24. The computer program product of claim 23 , wherein the instructions to decode the RAP frame includes instruction to decode a channel switch frame comprising one or more network abstraction layer (NAL) units.
25. A method comprising:
decoding one or more of back-to-back video media frames of a block of consecutive video media frames, each with a same frame identification (ID) number that identifies a relative decode order of the corresponding frame, with a first video media frame of the back-to-back video media frames being a random access point (RAP) frame and a second video media frame of the back-to-back video media frames being a non-RAP frame.
26. The method of claim 25 , wherein the decoding step includes decoding only one of the back-to-back frames.
27. The method of claim 26 , further comprising the step of providing both back-to-back frames to a decoder.
28. The method of claim 25 , wherein the decoding step includes decoding the RAP frame; and dropping frames in output order before the RAP frame.
29. The method of claim 28 , wherein the decoding of the RAP frame includes decoding a channel switch frame comprising one or more network abstraction layer (NAL) units.
30. A method comprising the step of:
encoding one or more of back-to-back video media frames of a block of consecutive video media frames, each with the same frame identification (ID) number that identifies a relative decode order of the corresponding frame, with a first video media frame of the back-to-back video media frames being a random access point (RAP) frame and a second video media frame of the back-to-back video media frames being a non-RAP frame.
31. A system comprising:
an encoder operative to encode one or more of back-to-back video media frames of a block of consecutive video media frames, each with a same frame identification (ID) number that identifies a relative decode order of the corresponding frame, with a first video media frame of the back-to-back frames being a random access point (RAP) frame and a second video media frame of the back-to-back video media frames being a non-RAP frame; and
a decoder operative to decode one or more of the back-to-back video media frames to switch channels or to facilitate error recovery.
32. A system comprising:
an encoder operative to generate and broadcast a channel switch frame (CSF) from one or more network abstraction layer (NAL) units to enable random access points in a coded bitstream, wherein at least one of the NAL units comprises an Instantaneous Decoding Refresh (IDR) NAL unit having a non-zero frame identification number equal to a frame number of a corresponding P-slice; and
a decoder operative to decode the CSF to cause switching from one channel to another channel or to facilitate error recovery.
33. A method comprising:
generating a channel switch frame (CSF) from one or more network abstraction layer (NAL) units to enable random access points in a coded bitstream, wherein at least one of the NAL units comprises an Instantaneous Decoding Refresh (IDR) NAL unit having a non-zero frame identification number equal to a frame number of a corresponding P-slice.
34. The method of claim 33 , wherein the IDR NAL unit has a non-zero picture order count (POC) number.
35. The method of claim 33 , wherein the generating step further includes generating the CSF with at least two additional NAL units, the at least two additional NAL units comprises a sequence parameter set (SPS) NAL unit and a picture parameter set (PPS) NAL unit.
36. The method of claim 33 , wherein the generating step includes generating the CSF with an I-frame NAL unit.
37. The method of claim 33 , further comprising the step of broadcasting the CSF as a random access point (RAP) frame to effectuate channel switching.
38. The method of claim 37 , further comprising receiving the CSF; and switching from one channel to another channel in response to the received CSF.
39. The method of claim 37 , further comprising receiving the CSF; and recovering from an error in the coded bitstream in response to the received CSF.