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pixfmt : Add GRAY12
3 novembre 2016, par Luca Barbato -
configure : Silence lld-link when getting the version number
3 novembre 2016, par Martin Storsjöconfigure: Silence lld-link when getting the version number In recent lld-link versions, this command prints the version to stdout, but also prints an error to stderr: $ lld-link -flavor gnu --version LLD 4.0.0 (trunk 285641) lld-link: error: no input files lld-link: error: target emulation unknown: -m or at least one .o file required Signed-off-by: Martin Storsjö <martin@martin.st>
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options_table : Remove a now unnecessary include of config.h
3 novembre 2016, par Martin Storsjöoptions_table: Remove a now unnecessary include of config.h The include of config.h was added in 2012 in 1d9c2dc8, due to the use of CONFIG_SNOW_ENCODER ifdefs within options_table.h. When the snow codec was dropped later (in a0c5917f8 in 2013), this include no longer served any purpose. options_table.h is included in builds for the host as well, when building documentation. config.h should not be included in code that is built for the host, since it can contain workarounds for the target compiler/environment, like adding a missing define of restrict, defining getenv(x) to NULL for environments that lack getenv. The seemingly innocent include reordering in 2025d37871 broke builds that have getenv(x) defined to NULL in config.h (Windows CE and Windows Phone/RT), since libavcodec/options_table.h include config.h, while libavformat/options_table.h end up bringing in more system headers, and those system headers can contain a proper definition of getenv, which clash with the getenv define in config.h. This was avoided earlier as long as libavformat/options_table.h (or avformat.h) was included before libavcodec/options_table.h. This fixes builds for Windows Phone/RT and CE. Signed-off-by: Martin Storsjö <martin@martin.st>
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arm : vp9 : Add NEON optimizations of VP9 MC functions
3 novembre 2016, par Martin Storsjöarm: vp9: Add NEON optimizations of VP9 MC functions 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. Signed-off-by: Martin Storsjö <martin@martin.st> -
vp9 : Flip the order of arguments in MC functions
3 novembre 2016, par Martin Storsjövp9: Flip the order of arguments in MC functions This makes it match the pattern already used for VP8 MC functions. This also makes the signature match ffmpeg's version of these functions, easing porting of code in both directions. Signed-off-by: Martin Storsjö <martin@martin.st>
