High quality low bitrate video coding by enabling and disabling a non-residual mode
View Patent ↗A method for encoding video, comprising the steps of (A) encoding a number of macroblocks of a video signal with a non-residual mode disabled, (B) checking each of the macroblocks for a null information pattern, and (C) re-encoding each of the macroblocks having the null information pattern with the non-residual mode enabled.
1. A method for encoding video, comprising the steps of:
(A) encoding a number of macroblocks of a video signal with a non-residual mode disabled;
(B) checking each of said macroblocks for a null information pattern;
(C) transmitting a subset of macroblocks in said macroblocks with said non-residual mode enabled, the subset of macroblocks having said null information pattern; and
wherein said non-residual mode is selected from a group consisting of a PSKIP mode, a DIRECT mode, a mode in which no previous macroblocks are re-encoded, and a mode in which no subsequent macroblocks are re-encoded.
2. The method according to claim 1 , wherein step (c) comprises:
replacing a coded representation for each of said macroblocks having said null information pattern with that corresponding to encoding with said non-residual mode enabled.
3. The method according to claim 1 , wherein said non-residual mode comprises a PSKIP mode in which said marcroblock having said null information pattern is based on a second presentation of a previous macroblock.
4. The method according to claim 1 , wherein said non-residual mode comprises a DIRECT mode.
5. The method according to claim 1 , wherein said null information pattern comprises a quantized macroblock having all zero DCT coefficients and zero motion vector difference information.
6. The method according to claim 1 , wherein said encoding comprises rate distortion optimized motion estimation and quantization.
7. The method according to claim 6 , further comprising the steps of:
(A-1) re-encoding said macroblocks with an increased quantization parameter;
(B-1) re-checking each of said macroblocks for said null information pattern;
(C-1) re-encoding each of said macroblocks having said null information pattern with said non-residual mode enabled; and
(D-1) in place of step (C-1), replacing coded representation of each said macroblocks having said null information pattern when said macroblock is coded with said non-residual mode.
8. The method according to claim 1 , wherein step (B) comprises exact bit pattern matching.
9. The method according to claim 1 , wherein step (B) comprises rate-distortion comparison of coded representation.
10. The method according to claim 1 , wherein said checking of null information pattern includes both exact bit pattern matching and rate-distortion comparison of coded representations.
11. A method for encoding video, comprising the steps of:
(A) receiving an encoded bitstream comprising a number of macroblocks, wherein said encoded bitstream was generated with a non-residual mode disabled;
(B) checking each of said macroblocks for a null information patter; and
(C) transmitting a subset of macroblocks in said macroblocks with said non-residual mode enabled, the subset of macroblocks having said null information pattern; and
wherein said non-residual mode is selected from a group consisting of a PSKIP mode, a DIRECT mode, a mode in which no previous macroblocks are re-encoded, and a mode in which no subsequent macroblocks are re-encoded.
12. An apparatus comprising:
an encoder circuit configured to encode a number of macroblocks of a video signal; with a non-residual mode disabled;
a detection circuit configured to check each of said macroblocks for a null information pattern;
a control circuit configured to initiate transmitting a subset of macroblocks in each of said macroblocks with said non-residual mode enabled, the subset of macroblocks having said null information pattern; and
wherein said non-residual mode is selected from a group consisting of a PSKIP mode, a DIRECT mode, a mode in which no previous macroblocks are re-encoded, and a mode in which no subsequent macroblocks are re-encoded.
13. The apparatus according to claim 12 , wherein said re-encoding is performed in said encoder.
14. The apparatus according to claim 12 , wherein said re-encoding is performed in a second encoder circuit.
15. The apparatus according to claim 14 , wherein said encoder circuit is implemented on the first integrated circuit and said second encoder circuit is implemented on a second integrated circuit.
16. The apparatus according to claim 12 , wherein said non-residual mode comprises a PSKIP mode in which said marcroblock having said null information pattern is based on a second presentation of a previous macroblock.
17. The apparatus according to claim 12 , wherein said non-residual mode comprises a DIRECT mode.