Use a combination of table lookups and pshufb to convert coefficients
to zero run/level format. Two 16-entry lookup tables are used for a
total of 192 bytes worth of tables. (The existing SSE2 version uses a
table of size 2048 bytes.)
Speedup is ~1.5x-3x as compared with the SSE2 version on Haswell (the
speedup is greater for input with many trailing zeros).
The use of popcnt makes it require SSE4.2. This can be replaced with
a small LUT and accumulation which would reduce the requirement to
SSSE3.
WelsQuantFour4x4Max_avx2 (~2.06x speedup over SSE2)
WelsQuantFour4x4_avx2 (~2.32x speedup over SSE2)
WelsQuant4x4Dc_avx2 (~1.49x speedup over SSE2)
WelsQuant4x4_avx2 (~1.42x speedup over SSE2)
WelsSampleSatd16x16_avx2 (~2.31x speedup over SSE4.1 on Haswell).
WelsSampleSatd16x8_avx2 (~2.19x speedup over SSE4.1 on Haswell).
WelsSampleSatd8x16_avx2 (~1.68x speedup over SSE4.1 on Haswell).
WelsSampleSatd8x8_avx2 (~1.53x speedup over SSE4.1 on Haswell).
The "Video signal type present" information is written to the output
video file when it is created, and later is used by the decoder to
properly decode the compressed video data. The saved attributes
are:
- format type (PAL, NTSC, etc.)
- color primaries (BT709, SMPTE170M, etc.)
- transfer characteristics (BT709, SMPTE170M, etc.)
- color matrix ((BT709, SMPTE170M, etc.)
These modifications allow the client to specify these attributes
and, if specified, makes sure they are written to the output file.
The "Video signal type present" information is written to the output
video file when it is created, and later is used by the decoder to
properly decode the compressed video data. The saved attributes
are:
- format type (PAL, NTSC, etc.)
- color primaries (BT709, SMPTE170M, etc.)
- transfer characteristics (BT709, SMPTE170M, etc.)
- color matrix ((BT709, SMPTE170M, etc.)
These modifications allow the client to specify these attributes
and, if specified, makes sure they are written to the output file.
We do four blocks at a time when possible, but need to handle
single blocks at a time for intra prediction.
~3.15x speedup over MMX for the DCT on Haswell.
~2.94x speedup over MMX for the IDCT on Haswell.
Returns diminish with increasing vector length because a larger
proportion of the time is spent on load/store/shuffling.
We do four blocks at a time when possible, but need to handle
single blocks at a time for intra prediction.
~2.31x speedup over MMX for the DCT on Haswell.
~1.92x speedup over MMX for the IDCT on Haswell.
