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  1. 15 Nov, 2016 8 commits
    • Martin Storsjö's avatar
      arm: vp9: Add NEON optimizations of VP9 MC functions · 68caef9d
      Martin Storsjö authored 
      This work is sponsored by, and copyright, Google.

The filter coefficients are signed values, where the product of the
multiplication with one individual filter coefficient doesn't
overflow a 16 bit signed value (the largest filter coefficient is
127). But when the products are accumulated, the resulting sum can
overflow the 16 bit signed range. Instead of accumulating in 32 bit,
we accumulate the largest product (either index 3 or 4) last with a
saturated addition.

(The VP8 MC asm does something similar, but slightly simpler, by
accumulating each half of the filter separately. In the VP9 MC
filters, each half of the filter can also overflow though, so the
largest component has to be handled individually.)

Examples of relative speedup compared to the C version, from checkasm:
                       Cortex      A7     A8     A9    A53
vp9_avg4_neon:                   1.71   1.15   1.42   1.49
vp9_avg8_neon:                   2.51   3.63   3.14   2.58
vp9_avg16_neon:                  2.95   6.76   3.01   2.84
vp9_avg32_neon:                  3.29   6.64   2.85   3.00
vp9_avg64_neon:                  3.47   6.67   3.14   2.80
vp9_avg_8tap_smooth_4h_neon:     3.22   4.73   2.76   4.67
vp9_avg_8tap_smooth_4hv_neon:    3.67   4.76   3.28   4.71
vp9_avg_8tap_smooth_4v_neon:     5.52   7.60   4.60   6.31
vp9_avg_8tap_smooth_8h_neon:     6.22   9.04   5.12   9.32
vp9_avg_8tap_smooth_8hv_neon:    6.38   8.21   5.72   8.17
vp9_avg_8tap_smooth_8v_neon:     9.22  12.66   8.15  11.10
vp9_avg_8tap_smooth_64h_neon:    7.02  10.23   5.54  11.58
vp9_avg_8tap_smooth_64hv_neon:   6.76   9.46   5.93   9.40
vp9_avg_8tap_smooth_64v_neon:   10.76  14.13   9.46  13.37
vp9_put4_neon:                   1.11   1.47   1.00   1.21
vp9_put8_neon:                   1.23   2.17   1.94   1.48
vp9_put16_neon:                  1.63   4.02   1.73   1.97
vp9_put32_neon:                  1.56   4.92   2.00   1.96
vp9_put64_neon:                  2.10   5.28   2.03   2.35
vp9_put_8tap_smooth_4h_neon:     3.11   4.35   2.63   4.35
vp9_put_8tap_smooth_4hv_neon:    3.67   4.69   3.25   4.71
vp9_put_8tap_smooth_4v_neon:     5.45   7.27   4.49   6.52
vp9_put_8tap_smooth_8h_neon:     5.97   8.18   4.81   8.56
vp9_put_8tap_smooth_8hv_neon:    6.39   7.90   5.64   8.15
vp9_put_8tap_smooth_8v_neon:     9.03  11.84   8.07  11.51
vp9_put_8tap_smooth_64h_neon:    6.78   9.48   4.88  10.89
vp9_put_8tap_smooth_64hv_neon:   6.99   8.87   5.94   9.56
vp9_put_8tap_smooth_64v_neon:   10.69  13.30   9.43  14.34

For the larger 8tap filters, the speedup vs C code is around 5-14x.

This is significantly faster than libvpx's implementation of the same
functions, at least when comparing the put_8tap_smooth_64 functions
(compared to vpx_convolve8_horiz_neon and vpx_convolve8_vert_neon from
libvpx).

Absolute runtimes from checkasm:
                          Cortex      A7        A8        A9       A53
vp9_put_8tap_smooth_64h_neon:    20150.3   14489.4   19733.6   10863.7
libvpx vpx_convolve8_horiz_neon: 52623.3   19736.4   21907.7   25027.7

vp9_put_8tap_smooth_64v_neon:    14455.0   12303.9   13746.4    9628.9
libvpx vpx_convolve8_vert_neon:  42090.0   17706.2   17659.9   16941.2

Thus, on the A9, the horizontal filter is only marginally faster than
libvpx, while our version is significantly faster on the other cores,
and the vertical filter is significantly faster on all cores. The
difference is especially large on the A7.

The libvpx implementation does the accumulation in 32 bit, which
probably explains most of the differences.

This is an adapted cherry-pick from libav commits
ffbd1d2b,
392caa65,
557c1675 and
11623217.
Signed-off-by: 's avatarRonald S. Bultje <rsbultje@gmail.com>
      68caef9d
    • Martin Storsjö's avatar
      arm: Clear the gp register alias at the end of functions · 86c5a23e
      Martin Storsjö authored 
      We reset .Lpic_gp to zero at the start of each function, which means
that the logic within movrelx for clearing gp when necessary will
be missed.

This fixes using movrelx in different functions with a different
helper register.

This is cherry-picked from libav commit
824e8c28.
Signed-off-by: 's avatarRonald S. Bultje <rsbultje@gmail.com>
      86c5a23e
    • Martin Storsjö's avatar
      vp9dsp: Deduplicate the subpel filters · 6409e9b6
      Martin Storsjö authored 
      Make them aligned, to allow efficient access to them from simd.

This is an adapted cherry-pick from libav commit
a4cfcddc.
Signed-off-by: 's avatarRonald S. Bultje <rsbultje@gmail.com>
      6409e9b6
    • Michael Niedermayer's avatar
      avcodec/ituh263dec: Avoid spending a long time in slice sync · 2baf36ca
      Michael Niedermayer authored 
      Fixes: 177/fuzz-3-ffmpeg_VIDEO_AV_CODEC_ID_FLV1_fuzzer

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpegSigned-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
      2baf36ca
    • Ronald S. Bultje's avatar
      vp9: add avx2 iadst16 implementations. · 83a139e3
      Ronald S. Bultje authored 
      Also a small cosmetic change to the avx2 idct16 version to make it
explicit that one of the arguments to the write-out macros is unused
for >=avx2 (it uses pmovzxbw instead of punpcklbw).
      83a139e3
    • Michael Niedermayer's avatar
      avcodec/movtextdec: Add error message for tsmb_size check · 0eb31980
      Michael Niedermayer authored 
      Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
      0eb31980
    • Michael Niedermayer's avatar
      avcodec/movtextdec: Fix tsmb_size check==0 check · a6099057
      Michael Niedermayer authored 
      Fixes: 173/fuzz-3-ffmpeg_SUBTITLE_AV_CODEC_ID_MOV_TEXT_fuzzer

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpegSigned-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
      a6099057
    • Michael Niedermayer's avatar
      avcodec/movtextdec: Fix potential integer overflow · 6ea27157
      Michael Niedermayer authored 
      Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
      6ea27157
  3. 14 Nov, 2016 32 commits