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  • arm : Add NEON optimizations for 10 and 12 bit vp9 MC

    8 décembre 2016, par Martin Storsjö
    arm : Add NEON optimizations for 10 and 12 bit vp9 MC

    This work is sponsored by, and copyright, Google.
    

    The plain pixel put/copy functions are used from the 8 bit version,
    
for the double size (e.g. put16 uses ff_vp9_copy32_neon), and a new
    
copy128 is added.
    

    Compared with the 8 bit version, the filters can no longer use the
    
trick to accumulate in 16 bit with only saturation at the end, but now
    
the accumulators need to be 32 bit. This avoids the need to keep track
    
of which filter index is the largest though, reducing the size of the
    
executable code for these filters.
    

    For the horizontal filters, we only do 4 or 8 pixels wide in parallel
    
(while doing two rows at a time), since we don’t have enough register
    
space to filter 16 pixels wide.
    

    For the vertical filters, we still do 4 and 8 pixels in parallel just
    
as in the 8 bit case, but we need to store the output after every 2
    
rows instead of after every 4 rows.
    

    Examples of relative speedup compared to the C version, from checkasm :
    
                               Cortex    A7     A8     A9    A53
    
vp9_avg4_10bpp_neon :                   2.25   2.44   3.05   2.16
    
vp9_avg8_10bpp_neon :                   3.66   8.48   3.86   3.50
    
vp9_avg16_10bpp_neon :                  3.39   8.26   3.37   2.72
    
vp9_avg32_10bpp_neon :                  4.03  10.20   4.07   3.42
    
vp9_avg64_10bpp_neon :                  4.15  10.01   4.13   3.70
    
vp9_avg_8tap_smooth_4h_10bpp_neon :     3.38   6.22   3.41   4.75
    
vp9_avg_8tap_smooth_4hv_10bpp_neon :    3.89   6.39   4.30   5.32
    
vp9_avg_8tap_smooth_4v_10bpp_neon :     5.32   9.73   6.34   7.31
    
vp9_avg_8tap_smooth_8h_10bpp_neon :     4.45   9.40   4.68   6.87
    
vp9_avg_8tap_smooth_8hv_10bpp_neon :    4.64   8.91   5.44   6.47
    
vp9_avg_8tap_smooth_8v_10bpp_neon :     6.44  13.42   8.68   8.79
    
vp9_avg_8tap_smooth_64h_10bpp_neon :    4.66   9.02   4.84   7.71
    
vp9_avg_8tap_smooth_64hv_10bpp_neon :   4.61   9.14   4.92   7.10
    
vp9_avg_8tap_smooth_64v_10bpp_neon :    6.90  14.13   9.57  10.41
    
vp9_put4_10bpp_neon :                   1.33   1.46   2.09   1.33
    
vp9_put8_10bpp_neon :                   1.57   3.42   1.83   1.84
    
vp9_put16_10bpp_neon :                  1.55   4.78   2.17   1.89
    
vp9_put32_10bpp_neon :                  2.06   5.35   2.14   2.30
    
vp9_put64_10bpp_neon :                  3.00   2.41   1.95   1.66
    
vp9_put_8tap_smooth_4h_10bpp_neon :     3.19   5.81   3.31   4.63
    
vp9_put_8tap_smooth_4hv_10bpp_neon :    3.86   6.22   4.32   5.21
    
vp9_put_8tap_smooth_4v_10bpp_neon :     5.40   9.77   6.08   7.21
    
vp9_put_8tap_smooth_8h_10bpp_neon :     4.22   8.41   4.46   6.63
    
vp9_put_8tap_smooth_8hv_10bpp_neon :    4.56   8.51   5.39   6.25
    
vp9_put_8tap_smooth_8v_10bpp_neon :     6.60  12.43   8.17   8.89
    
vp9_put_8tap_smooth_64h_10bpp_neon :    4.41   8.59   4.54   7.49
    
vp9_put_8tap_smooth_64hv_10bpp_neon :   4.43   8.58   5.34   6.63
    
vp9_put_8tap_smooth_64v_10bpp_neon :    7.26  13.92   9.27  10.92
    

    For the larger 8tap filters, the speedup vs C code is around 4-14x.
    

    Signed-off-by : Martin Storsjö <martin@martin.st>
    • [DH] libavcodec/arm/Makefile
    • [DH] libavcodec/arm/vp9dsp_init.h
    • [DH] libavcodec/arm/vp9dsp_init_10bpp_arm.c
    • [DH] libavcodec/arm/vp9dsp_init_12bpp_arm.c
    • [DH] libavcodec/arm/vp9dsp_init_16bpp_arm_template.c
    • [DH] libavcodec/arm/vp9dsp_init_arm.c
    • [DH] libavcodec/arm/vp9mc_16bpp_neon.S

  • ffmpeg : Encoder (codec amr_nb) not found for output stream #0:1

    23 mars 2017, par m.qayyum

    I’m using this command to convert flv to 3gp

    ffmpeg -y -i in.flv -ar 8000 -b:a 12.20k -ac 1 -s 176x144 out.3gp

    And it’s giving this error

    Encoder (codec amr_nb) not found for output stream #0:1

    I have searched for amr_nb packages on yum but didn’t able to find it.

    I’m on CentOS 7

    ffmpeg -version
    
ffmpeg version 2.6.8 Copyright (c) 2000-2016 the FFmpeg developers
    
built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-4)
    
configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic' --enable-bzlib --disable-crystalhd --enable-gnutls --enable-ladspa --enable-libass --enable-libcdio --enable-libdc1394 --enable-libfaac --enable-nonfree --enable-libfdk-aac --enable-nonfree --disable-indev=jack --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-openal --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libv4l2 --enable-libx264 --enable-libx265 --enable-libxvid --enable-x11grab --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-runtime-cpudetect
    
libavutil      54. 20.100 / 54. 20.100
    
libavcodec     56. 26.100 / 56. 26.100
    
libavformat    56. 25.101 / 56. 25.101
    
libavdevice    56.  4.100 / 56.  4.100
    
libavfilter     5. 11.102 /  5. 11.102
    
libavresample   2.  1.  0 /  2.  1.  0
    
libswscale      3.  1.101 /  3.  1.101
    
libswresample   1.  1.100 /  1.  1.100
    
libpostproc    53.  3.100 / 53.  3.100

    I’m not sure what’s missing.

    Edit :

    I followed this guide https://s3bubble.com/installing-ffmpeg-on-centos-6-6-in-usrlocalbin/ + alijandro’s advice.

  • arm : Add NEON optimizations for 10 and 12 bit vp9 loop filter

    5 janvier 2017, par Martin Storsjö
    arm : Add NEON optimizations for 10 and 12 bit vp9 loop filter

    This work is sponsored by, and copyright, Google.
    

    This is pretty much similar to the 8 bpp version, but in some senses
    
simpler. All input pixels are 16 bits, and all intermediates also fit
    
in 16 bits, so there’s no lengthening/narrowing in the filter at all.
    

    For the full 16 pixel wide filter, we can only process 4 pixels at a time
    
(using an implementation very much similar to the one for 8 bpp),
    
but we can do 8 pixels at a time for the 4 and 8 pixel wide filters with
    
a different implementation of the core filter.
    

    Examples of relative speedup compared to the C version, from checkasm :
    
                                   Cortex    A7     A8     A9    A53
    
vp9_loop_filter_h_4_8_10bpp_neon :          1.83   2.16   1.40   2.09
    
vp9_loop_filter_h_8_8_10bpp_neon :          1.39   1.67   1.24   1.70
    
vp9_loop_filter_h_16_8_10bpp_neon :         1.56   1.47   1.10   1.81
    
vp9_loop_filter_h_16_16_10bpp_neon :        1.94   1.69   1.33   2.24
    
vp9_loop_filter_mix2_h_44_16_10bpp_neon :   2.01   2.27   1.67   2.39
    
vp9_loop_filter_mix2_h_48_16_10bpp_neon :   1.84   2.06   1.45   2.19
    
vp9_loop_filter_mix2_h_84_16_10bpp_neon :   1.89   2.20   1.47   2.29
    
vp9_loop_filter_mix2_h_88_16_10bpp_neon :   1.69   2.12   1.47   2.08
    
vp9_loop_filter_mix2_v_44_16_10bpp_neon :   3.16   3.98   2.50   4.05
    
vp9_loop_filter_mix2_v_48_16_10bpp_neon :   2.84   3.64   2.25   3.77
    
vp9_loop_filter_mix2_v_84_16_10bpp_neon :   2.65   3.45   2.16   3.54
    
vp9_loop_filter_mix2_v_88_16_10bpp_neon :   2.55   3.30   2.16   3.55
    
vp9_loop_filter_v_4_8_10bpp_neon :          2.85   3.97   2.24   3.68
    
vp9_loop_filter_v_8_8_10bpp_neon :          2.27   3.19   1.96   3.08
    
vp9_loop_filter_v_16_8_10bpp_neon :         3.42   2.74   2.26   4.40
    
vp9_loop_filter_v_16_16_10bpp_neon :        2.86   2.44   1.93   3.88
    

    The speedup vs C code measured in checkasm is around 1.1-4x.
    
These numbers are quite inconclusive though, since the checkasm test
    
runs multiple filterings on top of each other, so later rounds might
    
end up with different codepaths (different decisions on which filter
    
to apply, based on input pixel differences).
    

    Based on START_TIMER/STOP_TIMER wrapping around a few individual
    
functions, the speedup vs C code is around 2-4x.
    

    Signed-off-by : Martin Storsjö <martin@martin.st>
    • [DH] libavcodec/arm/Makefile
    • [DH] libavcodec/arm/vp9dsp_init_16bpp_arm_template.c
    • [DH] libavcodec/arm/vp9lpf_16bpp_neon.S

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