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Another set of approved G.729 chunks (from decoder core)

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Originally committed as revision 15168 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Vladimir Voroshilov 2008-09-03 01:07:03 +00:00
parent 4834eb191c
commit bc165ee392
1 changed files with 43 additions and 0 deletions
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43
libavcodec/g729dec.c
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@ -79,6 +79,49 @@ static inline int g729_get_parity(uint8_t value)
return (0x6996966996696996ULL >> (value >> 2)) & 1;
}
/*
This filter enhances harmonic components of the fixed-codebook vector to
improve the quality of the reconstructed speech.
/ fc_v[i], i < pitch_delay
fc_v[i] = <
\ fc_v[i] + gain_pitch * fc_v[i-pitch_delay], i >= pitch_delay
*/
ff_acelp_weighted_vector_sum(
fc + pitch_delay_int[i],
fc + pitch_delay_int[i],
fc,
1 << 14,
av_clip(ctx->gain_pitch, SHARP_MIN, SHARP_MAX),
0,
14,
ctx->subframe_size - pitch_delay_int[i]);
ctx->gain_pitch = cb_gain_1st_8k[parm->gc_1st_index[i]][0] +
cb_gain_2nd_8k[parm->gc_2nd_index[i]][0];
gain_corr_factor = cb_gain_1st_8k[parm->gc_1st_index[i]][1] +
cb_gain_2nd_8k[parm->gc_2nd_index[i]][1];
/* Routine requires rounding to lowest. */
ff_acelp_interpolate(
ctx->exc + i*ctx->subframe_size,
ctx->exc + i*ctx->subframe_size - pitch_delay_3x/3,
ff_acelp_interp_filter,
6,
(pitch_delay_3x%3)<<1,
10,
ctx->subframe_size);
ff_acelp_weighted_vector_sum(
ctx->exc + i * ctx->subframe_size,
ctx->exc + i * ctx->subframe_size,
fc,
(!voicing && ctx->frame_erasure) ? 0 : ctx->gain_pitch,
( voicing && ctx->frame_erasure) ? 0 : ctx->gain_code,
1<<13,
14,
ctx->subframe_size);
AVCodec g729_decoder =
{
"g729",