diff options
author | Justin Ruggles <justin.ruggles@gmail.com> | 2009-09-27 07:16:51 +0000 |
---|---|---|
committer | Justin Ruggles <justin.ruggles@gmail.com> | 2009-09-27 07:16:51 +0000 |
commit | 8b11b44ea73f8052c8c2b606532037df848b1d76 (patch) | |
tree | 0cef29d1ab4e2d8a317d023c4279c12010872c4c | |
parent | e96f885aa092958cc0d54bbb191b82a0796518a4 (diff) | |
download | ffmpeg-8b11b44ea73f8052c8c2b606532037df848b1d76.tar.gz |
Rearrange loop structure for approx. 35-50% faster calc_transform_coeffs_cpl()
depending on content.
Originally committed as revision 20055 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r-- | libavcodec/ac3dec.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index efeb284b4a..85c60241ed 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -416,17 +416,22 @@ static void calc_transform_coeffs_cpl(AC3DecodeContext *s) bin = s->start_freq[CPL_CH]; for (band = 0; band < s->num_cpl_bands; band++) { + int band_start = bin; int band_end = bin + s->cpl_band_sizes[band]; - for (; bin < band_end; bin++) { - for (ch = 1; ch <= s->fbw_channels; ch++) { - if (s->channel_in_cpl[ch]) { + for (ch = 1; ch <= s->fbw_channels; ch++) { + if (s->channel_in_cpl[ch]) { + int64_t cpl_coord = s->cpl_coords[ch][band]; + for (bin = band_start; bin < band_end; bin++) { s->fixed_coeffs[ch][bin] = ((int64_t)s->fixed_coeffs[CPL_CH][bin] * - (int64_t)s->cpl_coords[ch][band]) >> 23; - if (ch == 2 && s->phase_flags[band]) - s->fixed_coeffs[ch][bin] = -s->fixed_coeffs[ch][bin]; + cpl_coord) >> 23; + } + if (ch == 2 && s->phase_flags[band]) { + for (bin = band_start; bin < band_end; bin++) + s->fixed_coeffs[2][bin] = -s->fixed_coeffs[2][bin]; } } } + bin = band_end; } } |