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| author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2015-12-24 13:03:28 -0500 |
|---|---|---|
| committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-03-25 18:08:24 -0400 |
| commit | 1fd6d47fac3eb5e29fbd44853d884f7ce6f50b2d (patch) | |
| tree | 40adc36ae538d988d826c0b8708731ba810798d8 | |
| parent | b4f7c2159fd9046f55001310d587a4b857183f98 (diff) | |
| download | opus-1fd6d47fac3eb5e29fbd44853d884f7ce6f50b2d.tar.gz | |
Quality: Adds SILK rate interpolation function
| -rw-r--r-- | src/opus_encoder.c | 57 |
1 files changed, 45 insertions, 12 deletions
diff --git a/src/opus_encoder.c b/src/opus_encoder.c index 9dfe6b02..c442bde5 100644 --- a/src/opus_encoder.c +++ b/src/opus_encoder.c @@ -935,6 +935,49 @@ opus_val16 compute_stereo_width(const opus_val16 *pcm, int frame_size, opus_int3 return EXTRACT16(MIN32(Q15ONE, MULT16_16(20, mem->max_follower))); } +static int compute_silk_rate_for_hybrid(int rate, int bandwidth, int frame20ms, int vbr) { + int entry; + int i; + int N; + int silk_rate; + static int rate_table[][5] = { + /* |total| |-------- SILK------------| + SWB-10 FB-10 SWB-20 FB-20 */ + { 0, 0, 0, 0, 0}, + {12000, 10000, 10000, 10000, 10000}, + {16000, 14000, 14000, 14000, 14000}, + {20000, 16000, 16000, 16000, 16000}, + {24000, 18000, 18000, 18000, 18000}, + {32000, 22000, 22000, 22000, 22000}, + {64000, 38000, 38000, 38000, 38000} + }; + entry = 1 + 2*frame20ms + (bandwidth==OPUS_BANDWIDTH_FULLBAND); + N = sizeof(rate_table)/sizeof(rate_table[0]); + for (i=1;i<N;i++) + { + if (rate_table[i][0] > rate) break; + } + if (i == N) + { + silk_rate = rate_table[i-1][entry]; + /* For now, just give 50% of the extra bits to SILK. */ + silk_rate += (rate-rate_table[i-1][0])/2; + } else { + opus_int32 lo, hi, x0, x1; + lo = rate_table[i-1][entry]; + hi = rate_table[i][entry]; + x0 = rate_table[i-1][0]; + x1 = rate_table[i][0]; + silk_rate = (lo*(x1-rate) + hi*(rate-x0))/(x1-x0); + } + if (!vbr) + { + if (silk_rate > 8000) + silk_rate -= 1000; + } + return silk_rate; +} + opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_size, unsigned char *data, opus_int32 out_data_bytes, int lsb_depth, const void *analysis_pcm, opus_int32 analysis_size, int c1, int c2, @@ -1495,18 +1538,8 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_ if( st->mode == MODE_HYBRID ) { int HB_gain_ref; /* Base rate for SILK */ - st->silk_mode.bitRate = st->stream_channels * ( 5000 + 1000 * ( st->Fs == 100 * frame_size ) ); - if( curr_bandwidth == OPUS_BANDWIDTH_SUPERWIDEBAND ) { - /* SILK gets 2/3 of the remaining bits */ - st->silk_mode.bitRate += ( total_bitRate - st->silk_mode.bitRate ) * 2 / 3; - } else { /* FULLBAND */ - /* SILK gets 3/5 of the remaining bits */ - st->silk_mode.bitRate += ( total_bitRate - st->silk_mode.bitRate ) * 3 / 5; - } - /* Don't let SILK use more than 80% */ - if( st->silk_mode.bitRate > total_bitRate * 4/5 ) { - st->silk_mode.bitRate = total_bitRate * 4/5; - } + st->silk_mode.bitRate = compute_silk_rate_for_hybrid(total_bitRate, + curr_bandwidth, st->Fs == 50 * frame_size, st->use_vbr); if (!st->energy_masking) { /* Increasingly attenuate high band when it gets allocated fewer bits */ |