diff options
| author | Mans Rullgard <mans@mansr.com> | 2011-10-23 17:39:49 +0100 |
|---|---|---|
| committer | Mans Rullgard <mans@mansr.com> | 2011-11-25 13:19:53 +0000 |
| commit | 00a856e3f95214c54a878b7cbd6e8ae8c5ce3ca9 (patch) | |
| tree | 5fa20f30bafc61e71df1b89370f03b1dbf69505d /libavcodec/dca.c | |
| parent | 035af998ad03020a3dda4e662dfb97c68bbabaaa (diff) | |
| download | ffmpeg-00a856e3f95214c54a878b7cbd6e8ae8c5ce3ca9.tar.gz | |
dca: ARMv6 optimised decode_blockcode()
This is a hand-tuned version of the code with impossible parts of
the FASTDIV function ommitted.
2-5% faster overall on Cortex-A8.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Diffstat (limited to 'libavcodec/dca.c')
| -rw-r--r-- | libavcodec/dca.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/libavcodec/dca.c b/libavcodec/dca.c index 7f7bcf9cfd..b310638dc1 100644 --- a/libavcodec/dca.c +++ b/libavcodec/dca.c @@ -1038,6 +1038,7 @@ static void dca_downmix(float *samples, int srcfmt, } +#ifndef decode_blockcodes /* Very compact version of the block code decoder that does not use table * look-up but is slightly slower */ static int decode_blockcode(int code, int levels, int *values) @@ -1051,13 +1052,15 @@ static int decode_blockcode(int code, int levels, int *values) code = div; } - if (code == 0) - return 0; - else { - av_log(NULL, AV_LOG_ERROR, "ERROR: block code look-up failed\n"); - return AVERROR_INVALIDDATA; - } + return code; +} + +static int decode_blockcodes(int code1, int code2, int levels, int *values) +{ + return decode_blockcode(code1, levels, values) | + decode_blockcode(code2, levels, values + 4); } +#endif static const uint8_t abits_sizes[7] = { 7, 10, 12, 13, 15, 17, 19 }; static const uint8_t abits_levels[7] = { 3, 5, 7, 9, 13, 17, 25 }; @@ -1125,16 +1128,20 @@ static int dca_subsubframe(DCAContext * s, int base_channel, int block_index) if (abits >= 11 || !dca_smpl_bitalloc[abits].vlc[sel].table){ if (abits <= 7){ /* Block code */ - int block_code1, block_code2, size, levels; + int block_code1, block_code2, size, levels, err; size = abits_sizes[abits-1]; levels = abits_levels[abits-1]; block_code1 = get_bits(&s->gb, size); - /* FIXME Should test return value */ - decode_blockcode(block_code1, levels, block); block_code2 = get_bits(&s->gb, size); - decode_blockcode(block_code2, levels, &block[4]); + err = decode_blockcodes(block_code1, block_code2, + levels, block); + if (err) { + av_log(s->avctx, AV_LOG_ERROR, + "ERROR: block code look-up failed\n"); + return AVERROR_INVALIDDATA; + } }else{ /* no coding */ for (m = 0; m < 8; m++) |