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| author | Reynaldo H. Verdejo Pinochet <reynaldo@opendot.cl> | 2009-11-04 19:29:29 +0000 |
|---|---|---|
| committer | Reynaldo H. Verdejo Pinochet <reynaldo@opendot.cl> | 2009-11-04 19:29:29 +0000 |
| commit | 0c50f8e6ccda2ff0b265d36412fae103b276af2e (patch) | |
| tree | b9f3d071e6c48f011ecc1ba3229b71ceeb60d95a /libavcodec/acelp_vectors.h | |
| parent | 223217746c5beaa6110ce9ade2a582fc10d3d630 (diff) | |
| download | ffmpeg-0c50f8e6ccda2ff0b265d36412fae103b276af2e.tar.gz | |
Implement ff_scale_vector_to_given_sum_of_squares()
to aid generic gain control routines. Changes
for qcelp are included. Patch Collin McQuillan.
Originally committed as revision 20450 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/acelp_vectors.h')
| -rw-r--r-- | libavcodec/acelp_vectors.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/libavcodec/acelp_vectors.h b/libavcodec/acelp_vectors.h index 58cd84c841..a711160d4c 100644 --- a/libavcodec/acelp_vectors.h +++ b/libavcodec/acelp_vectors.h @@ -176,4 +176,22 @@ void ff_weighted_vector_sumf(float *out, const float *in_a, const float *in_b, void ff_adaptative_gain_control(float *buf_out, float speech_energ, int size, float alpha, float *gain_mem); +/** + * Set the sum of squares of a signal by scaling + * + * @param out output samples + * @param in input samples + * @param sum_of_squares new sum of squares + * @param n number of samples + * + * @note If the input is zero (or its energy underflows), the output is zero. + * This is the behavior of AGC in the AMR reference decoder. The QCELP + * reference decoder seems to have undefined behavior. + * + * TIA/EIA/IS-733 2.4.8.3-2/3/4/5, 2.4.8.6 + * 3GPP TS 26.090 6.1 (6) + */ +void ff_scale_vector_to_given_sum_of_squares(float *out, const float *in, + float sum_of_squares, const int n); + #endif /* AVCODEC_ACELP_VECTORS_H */ |