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| author | Ben Avison <bavison@riscosopen.org> | 2014-03-20 18:58:38 +0000 |
|---|---|---|
| committer | Martin Storsjö <martin@martin.st> | 2014-03-26 19:54:12 +0200 |
| commit | fcf5fc444522d24caa9907225802817ae788f511 (patch) | |
| tree | 52e963748ed754a57144eb3dfc8080278da6ef7c /libavcodec | |
| parent | 483321fe789566dcb27b6387c00ea16dd86bc587 (diff) | |
| download | ffmpeg-fcf5fc444522d24caa9907225802817ae788f511.tar.gz | |
truehd: tune VLC decoding for ARM.
Profiling on a Raspberry Pi revealed the best performance to correspond
with VLC_BITS = 5. Results for overall audio decode and the get_vlc2 function
in particular are as follows:
Before After
Mean StdDev Mean StdDev Confidence Change
6:2 total 348.8 20.1 339.6 15.1 88.8% +2.7% (insignificant)
6:2 function 38.1 8.1 26.4 4.1 100.0% +44.5%
8:2 total 339.1 15.4 324.5 15.5 99.4% +4.5%
8:2 function 33.8 7.0 27.3 5.6 99.7% +23.6%
6:6 total 604.6 20.8 572.8 20.6 100.0% +5.6%
6:6 function 95.8 8.4 68.9 8.2 100.0% +39.1%
8:8 total 766.4 17.6 741.5 21.2 100.0% +3.4%
8:8 function 106.0 11.4 86.1 9.9 100.0% +23.1%
Signed-off-by: Martin Storsjö <martin@martin.st>
Diffstat (limited to 'libavcodec')
| -rw-r--r-- | libavcodec/mlpdec.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/libavcodec/mlpdec.c b/libavcodec/mlpdec.c index c0f2d6a7fa..e0415f5707 100644 --- a/libavcodec/mlpdec.c +++ b/libavcodec/mlpdec.c @@ -37,9 +37,16 @@ #include "mlp_parser.h" #include "mlpdsp.h" #include "mlp.h" +#include "config.h" /** number of bits used for VLC lookup - longest Huffman code is 9 */ +#if ARCH_ARM +#define VLC_BITS 5 +#define VLC_STATIC_SIZE 64 +#else #define VLC_BITS 9 +#define VLC_STATIC_SIZE 512 +#endif typedef struct SubStream { /// Set if a valid restart header has been read. Otherwise the substream cannot be decoded. @@ -190,13 +197,13 @@ static av_cold void init_static(void) if (!huff_vlc[0].bits) { INIT_VLC_STATIC(&huff_vlc[0], VLC_BITS, 18, &ff_mlp_huffman_tables[0][0][1], 2, 1, - &ff_mlp_huffman_tables[0][0][0], 2, 1, 512); + &ff_mlp_huffman_tables[0][0][0], 2, 1, VLC_STATIC_SIZE); INIT_VLC_STATIC(&huff_vlc[1], VLC_BITS, 16, &ff_mlp_huffman_tables[1][0][1], 2, 1, - &ff_mlp_huffman_tables[1][0][0], 2, 1, 512); + &ff_mlp_huffman_tables[1][0][0], 2, 1, VLC_STATIC_SIZE); INIT_VLC_STATIC(&huff_vlc[2], VLC_BITS, 15, &ff_mlp_huffman_tables[2][0][1], 2, 1, - &ff_mlp_huffman_tables[2][0][0], 2, 1, 512); + &ff_mlp_huffman_tables[2][0][0], 2, 1, VLC_STATIC_SIZE); } ff_mlp_init_crc(); |