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| author | Vladimir Voroshilov <voroshil@gmail.com> | 2009-06-28 21:01:23 +0700 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2011-09-24 21:11:01 +0200 |
| commit | 682337672cd38b8e85acf11578a5130fa87ea1d7 (patch) | |
| tree | 9f667e00a6f95bce67f65cb466690939c69ad1a0 /libavcodec/g729postfilter.h | |
| parent | aca516cd676f5646004c649dc614760b937f4624 (diff) | |
| download | ffmpeg-682337672cd38b8e85acf11578a5130fa87ea1d7.tar.gz | |
Adaptive gain control
Diffstat (limited to 'libavcodec/g729postfilter.h')
| -rw-r--r-- | libavcodec/g729postfilter.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/libavcodec/g729postfilter.h b/libavcodec/g729postfilter.h index 07667994d5..956cde9ab7 100644 --- a/libavcodec/g729postfilter.h +++ b/libavcodec/g729postfilter.h @@ -40,6 +40,13 @@ #define FORMANT_PP_FACTOR_DEN 22938 //0.70 in Q15 /** + * gain adjustment factor (G.729, 4.2.4) + * 0.9875 in Q15 + */ +#define G729_AGC_FACTOR 32358 +#define G729_AGC_FAC1 (32768-G729_AGC_FACTOR) + +/** * 1.0 / (1.0 + 0.5) in Q15 * where 0.5 is the minimum value of * weight factor, controlling amount of long-term postfiltering @@ -92,4 +99,17 @@ void g729_postfilter(DSPContext *dsp, int16_t* ht_prev_data, int16_t* voicing, int16_t* pos_filter_data, int16_t *speech, int subframe_size); +/** + * \brief Adaptive gain control (4.2.4) + * \param gain_before (Q0) gain of speech before applying postfilters + * \param gain_after (Q0) gain of speech after applying postfilters + * \param speech [in/out] (Q0) signal buffer + * \param subframe_size length of subframe + * \param gain_prev (Q12) previous value of gain coefficient + * + * \return (Q12) last value of gain coefficient + */ +int16_t g729_adaptive_gain_control(int gain_before, int gain_after, int16_t *speech, + int subframe_size, int16_t gain_prev); + #endif // FFMPEG_G729POSTFILTER_H |