avcodec/dct-test: correct output bias of prores idct

This way the output values make sense

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/dct-test: reproduce 4..1019 clipping when testing prores IDCT

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
hevc: clip pixels when transquant bypass is used

Fixes: asan_stack-oob_eae8e3_7333_WPP_B_ericsson_MAIN10_2.bit
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind

This is a more proper fix than 5856bca360c5bc3e340a357d91b1f993c80a7bea

The reconstructed picture should always be clipped (see section 8.6.5),
previously we did not clip coding units where
cu_transquant_bypass_flag == 1

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
hevc: remove useless clip in FUNC(sao_band_filter)()

The src buffer should only contain values in the interval
[0, (1 << BIT_DEPTH) - 1]. Since shift = (BIT_DEPTH - 5), src[x] >> shift
must be in the interval [0, 31], so no clip is needed.

This removes the code that was changed in 5856bca360c5bc3e340a357d91b1f993c80a7bea
as the clip that was repositioned in that commit is removed

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/dct-test: add support for C prores IDCT

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
examples/muxing: simplify video PTS setting

Rely on frame_count. Also more consistent with audio path.
avcodec/vp9/x86: add ff_vp9_loop_filter_[vh]_16_16_ssse3().

16795 decicycles in loop_filter_h_16_16_c, 16773104 runs, 4112 skips
17667 decicycles in loop_filter_v_16_16_c, 16773311 runs, 3905 skips

5259 decicycles in ff_vp9_loop_filter_h_16_16_ssse3, 8386752 runs, 1856 skips
3907 decicycles in ff_vp9_loop_filter_v_16_16_ssse3, 8387438 runs, 1170 skips

Overall decode time goes from:
  ./ffmpeg -threads 1 -i ~/samples/vp9/ped1080p.webm -f null -  8.20s user 0.02s system 99% cpu 8.225 total
to:
  ./ffmpeg -threads 1 -i ~/samples/vp9/ped1080p.webm -f null -  6.28s user 0.02s system 99% cpu 6.307 total

(46 to 60 fps)