implement intensity compensation for VC-1 decoding for Ivybridge and better #234
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Intensity compensation was not present for B-frames, but only for P-frames. When a P-frame flags intensity compensation for its forward reference frame, all subsequent B-frames that use this reference frame as well, need to do intensity compensation as well.
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Could you please add a line of 'Fixes #xxx' to the commit message so that others know which issue is resolved by this commit? |
| intensitycomp_single_fwd = gen7_vc1_surface->intensity_compensation; | ||
| luma_scale1 = gen7_vc1_surface->luma_scale; | ||
| luma_shift1 = gen7_vc1_surface->luma_shift; | ||
| } |
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Does P frame also use the parameters from the reference frame? the commit message only says all subsequent B-frames need to do intensity compensation.
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The commit message only referenced the changes in intensity compensation. For P-frames intensity compensation was already working.
It is the P-frame that sets the parameters for its reference frame. Subsequently, the P-frame also uses this intensity compensated reference frame. Any B-frames that follow this P-frame and that reference that same reference frame also use the intensity compensation on the reference frame. (See 8.3.8 in VC-1 spec).
The patch stores the intensity compensation status with each surface. When such a surface is used as a reference, the stored intensity compensation status is used to program the graphics hardware.
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thanks for the explanation in detail
Intensity compensation was not present for B-frames, but only for P-frames. When a P-frame flags intensity compensation for its forward reference frame, all subsequent B-frames that use this reference frame as well, need to do intensity compensation as well.
VC1-decoder: implement intensity compensation for VC-1
Intensity compensation was not present for B-frames, but only for P-frames. When a P-frame flags intensity compensation for its forward reference frame, all subsequent B-frames that use this reference frame as well, need to do intensity compensation as well.
Fixes: #13 [IVB/BYT/BSW] Macroblocking artifact seen on a VC1 video file
Signed-off-by: Jerome Borsboom jerome.borsboom@carpalis.nl