Method and apparatus for video encoding with hypothetical reference decoder compliant bit allocation
View Patent ↗A method and apparatus are provided for encoding with hypothetical reference decoder compliant bit allocation. The apparatus includes an encoder ( 100 ) for encoding image data for a picture in a resultant bitstream by controlling a bit allocation during the encoding of the image data responsive to satisfying requirements for a subsequent decoding of the bitstream. The requirements relate to preventing at least one of an underflow condition and an overflow condition in a buffer during the subsequent decoding of the bitstream.
1. An apparatus, comprising:
an encoder for encoding image data for a picture in a bitstream by controlling a bit allocation during the encoding of the image data responsive to satisfying requirements for a subsequent decoding of the bitstream, the requirements relating to preventing at least one of an underflow condition and an overflow condition in a buffer during the subsequent decoding of the bitstream,
wherein the bit allocation is controlled by at least applying a bit constraint over a range of pictures contributing to the underflow condition, and
wherein the range of pictures starts at from a nearest picture prior to the underflow condition, the nearest picture having an arrival time at the buffer equal to an earliest arrival time at which a first bit for a buffering period to which the nearest picture belongs begin to enter the buffer.
2. The apparatus of claim 1 , wherein the requirements pertain to at least one of a particular video coding standard and a particular video coding recommendation.
3. The apparatus of claim 1 , wherein the range of pictures ends at a last picture corresponding to a burst of consecutive occurrences of the underflow condition.
4. The apparatus of claim 3 , wherein a total amount of a bit reduction resulting from the bit constraint is a bit equivalent of [t af (n)− tr,n (n)], wherein t af (n) denotes a final arrival time at which a last bit of the last picture enters the buffer, and t r,n (n) denotes a nominal removal time to entirely remove the last picture from the buffer.
5. The apparatus of claim 4 , wherein the bit reduction of each of the pictures within the range of pictures is proportional to a number of bits exceeding a bit average calculated over the range of pictures.
6. The apparatus of claim 1 , wherein said encoder encodes the bitstream in compliance with the multi-video video coding extension of the International Organization for Standardization/International Electrotechnical Commission Moving Picture Experts Group-4 Part 10 Advanced Video Coding Standard/International Telecommunication Union, Telecommunication Sector H.264 Recommendation.
7. The apparatus of claim 6 , wherein the bitstream is encoded in compliance with the BLU-RAY 3D Specification.
8. The apparatus of claim 7 , wherein the picture corresponds to multi-view video content for at least two views, and a common value of a syntax element initial_cpb_removal_delay is used for all operation points of a buffering period to which the picture applies, the common value being equal to a minimum value of the syntax element initial_cpb_removal_delay of all the operation points of the buffering period.
9. The apparatus of claim 1 , wherein the range of pictures over which the bit constraint is applied is less than all pictures in the bitstream.
10. The apparatus of claim 1 , wherein the buffering period comprises the set of access units between two instances of the buffering period SEI message in decoding order.
11. In a video encoder, a method, comprising:
encoding image data for a picture in a bitstream by controlling a bit allocation during the encoding of the image data responsive to satisfying requirements for a subsequent decoding of the bitstream, the requirements relating to preventing at least one of an underflow condition and an overflow condition in a buffer during the subsequent decoding of the bitstream,
wherein the bit allocation is controlled by at least applying a bit constraint over a range of pictures contributing to the underflow condition, and
wherein the range of pictures starts at from a nearest picture prior to the underflow condition, the nearest picture having an arrival time at the buffer equal to an earliest arrival time at which a first bit for a buffering period to which the nearest picture belongs begin to enter the buffer.
12. The method of claim 11 , wherein the requirements pertain to at least one of a particular video coding standard and a particular video coding recommendation.
13. The method of claim 11 , wherein the range of pictures ends at a last picture corresponding to a burst of consecutive occurrences of the underflow condition.
14. The method of claim 13 , wherein a total amount of a bit reduction resulting from the bit constraint is a bit equivalent of [t af (n)− tr,n (n)], wherein t af (n) denotes a final arrival time at which a last bit of the last picture enters the buffer, and t r,n (n) denotes a nominal removal time to entirely remove the last picture from the buffer.
15. The method of claim 14 , wherein the bit reduction of each of the pictures within the range of pictures is proportional to a number of bits exceeding a bit average calculated over the range of pictures.
16. The method of claim 11 , wherein the bitstream is encoded in compliance with the multi-video video coding extension of the International Organization for Standardization/International Electrotechnical Commission Moving Picture Experts Group-4 Part 10 Advanced Video Coding Standard/International Telecommunication Union, Telecommunication Sector H.264 Recommendation.
17. The method of claim 16 , wherein the bitstream is encoded in compliance with the BLU-RAY 3D Specification.
18. The method of claim 17 , wherein the picture corresponds to multi-view video content for at least two views, and a common value of a syntax element initial_cpb_removal_delay is used for all operation points of a buffering period to which the picture applies, the common value being equal to a minimum value of the syntax element initial_cpb_removal_delay of all the operation points.
19. The method of claim 11 , wherein the range of pictures over which the bit constraint is applied is less than all pictures in the bitstream.
20. The method of claim 11 , wherein the buffering period comprises the set of access units between two instances of the buffering period SEI message in decoding order.