diff options
author | Ronald S. Bultje <rsbultje@gmail.com> | 2010-04-21 21:50:08 +0400 |
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committer | Ronald S. Bultje <rsbultje@gmail.com> | 2010-04-21 21:50:08 +0400 |
commit | 805a83d506ff28aa3690b85851519fcb52b06169 (patch) | |
tree | 952d128dcb381d31bab39433bbbc922b5eb2804d /libavcodec/qcelpdec.c | |
parent | 5180a0b197457dd9ada538c0cd5e7470554dbfda (diff) |
Implement QCELP postfilter.
Originally committed as revision 22935 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/qcelpdec.c')
-rw-r--r-- | libavcodec/qcelpdec.c | 46 |
1 files changed, 41 insertions, 5 deletions
diff --git a/libavcodec/qcelpdec.c b/libavcodec/qcelpdec.c index 707cb21e74..25ef324475 100644 --- a/libavcodec/qcelpdec.c +++ b/libavcodec/qcelpdec.c @@ -37,6 +37,7 @@ #include "celp_math.h" #include "celp_filters.h" +#include "acelp_filters.h" #include "acelp_vectors.h" #include "lsp.h" @@ -74,6 +75,11 @@ typedef struct uint8_t pitch_lag[4]; uint16_t first16bits; uint8_t warned_buf_mismatch_bitrate; + + /* postfilter */ + float postfilter_synth_mem[10]; + float postfilter_agc_mem; + float postfilter_tilt_mem; } QCELPContext; /** @@ -695,6 +701,36 @@ static void warn_insufficient_frame_quality(AVCodecContext *avctx, message); } +static void postfilter(QCELPContext *q, float *samples, float *lpc) +{ + static const float pow_0_775[10] = { + 0.775000, 0.600625, 0.465484, 0.360750, 0.279582, + 0.216676, 0.167924, 0.130141, 0.100859, 0.078166 + }, pow_0_625[10] = { + 0.625000, 0.390625, 0.244141, 0.152588, 0.095367, + 0.059605, 0.037253, 0.023283, 0.014552, 0.009095 + }; + float lpc_s[10], lpc_p[10], pole_out[170], zero_out[160]; + int n; + + for (n = 0; n < 10; n++) { + lpc_s[n] = lpc[n] * pow_0_625[n]; + lpc_p[n] = lpc[n] * pow_0_775[n]; + } + + ff_celp_lp_zero_synthesis_filterf(zero_out, lpc_s, + q->formant_mem + 10, 160, 10); + memcpy(pole_out, q->postfilter_synth_mem, sizeof(float) * 10); + ff_celp_lp_synthesis_filterf(pole_out + 10, lpc_p, zero_out, 160, 10); + memcpy(q->postfilter_synth_mem, pole_out + 160, sizeof(float) * 10); + + ff_tilt_compensation(&q->postfilter_tilt_mem, 0.3, pole_out + 10, 160); + + ff_adaptive_gain_control(samples, pole_out + 10, + ff_dot_productf(q->formant_mem + 10, q->formant_mem + 10, 160), + 160, 0.9375, &q->postfilter_agc_mem); +} + static int qcelp_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { @@ -792,14 +828,14 @@ erasure: 10); formant_mem += 40; } - memcpy(q->formant_mem, q->formant_mem + 160, 10 * sizeof(float)); - // FIXME: postfilter and final gain control should be here. - // TIA/EIA/IS-733 2.4.8.6 + // postfilter, as per TIA/EIA/IS-733 2.4.8.6 + postfilter(q, outbuffer, lpc); + + memcpy(q->formant_mem, q->formant_mem + 160, 10 * sizeof(float)); - formant_mem = q->formant_mem + 10; for(i=0; i<160; i++) - *outbuffer++ = av_clipf(*formant_mem++, QCELP_CLIP_LOWER_BOUND, + outbuffer[i] = av_clipf(outbuffer[i], QCELP_CLIP_LOWER_BOUND, QCELP_CLIP_UPPER_BOUND); memcpy(q->prev_lspf, quantized_lspf, sizeof(q->prev_lspf)); |