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oops, non-normalized downmix to mono contaminated add_bias for non-simd float-to-int.

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Originally committed as revision 14740 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Loren Merritt
2008-08-13 23:30:28 +00:00
parent da0def34ec
commit 3b6516f7e7
1 changed files with 5 additions and 2 deletions
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7
libavcodec/ac3dec.c
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@ -606,6 +606,9 @@ static void do_rematrixing(AC3DecodeContext *s)
static inline void do_imdct(AC3DecodeContext *s, int channels) static inline void do_imdct(AC3DecodeContext *s, int channels)
{ {
int ch; int ch;
float add_bias = s->add_bias;
if(s->out_channels==1 && channels>1)
add_bias *= LEVEL_MINUS_3DB; // compensate for the gain in downmix
for (ch=1; ch<=channels; ch++) { for (ch=1; ch<=channels; ch++) {
if (s->block_switch[ch]) { if (s->block_switch[ch]) {
@ -614,13 +617,13 @@ static inline void do_imdct(AC3DecodeContext *s, int channels)
for(i=0; i<128; i++) for(i=0; i<128; i++)
x[i] = s->transform_coeffs[ch][2*i]; x[i] = s->transform_coeffs[ch][2*i];
ff_imdct_half(&s->imdct_256, s->tmp_output, x); ff_imdct_half(&s->imdct_256, s->tmp_output, x);
s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, s->add_bias, 128); s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128);
for(i=0; i<128; i++) for(i=0; i<128; i++)
x[i] = s->transform_coeffs[ch][2*i+1]; x[i] = s->transform_coeffs[ch][2*i+1];
ff_imdct_half(&s->imdct_256, s->delay[ch-1], x); ff_imdct_half(&s->imdct_256, s->delay[ch-1], x);
} else { } else {
ff_imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]); ff_imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]);
s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, s->add_bias, 128); s->dsp.vector_fmul_window(s->output[ch-1], s->delay[ch-1], s->tmp_output, s->window, add_bias, 128);
memcpy(s->delay[ch-1], s->tmp_output+128, 128*sizeof(float)); memcpy(s->delay[ch-1], s->tmp_output+128, 128*sizeof(float));
} }
} }