| /*********************************************************************** |
| Copyright (c) 2006-2011, Skype Limited. All rights reserved. |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| - Redistributions of source code must retain the above copyright notice, |
| this list of conditions and the following disclaimer. |
| - Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| - Neither the name of Internet Society, IETF or IETF Trust, nor the |
| names of specific contributors, may be used to endorse or promote |
| products derived from this software without specific prior written |
| permission. |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. |
| ***********************************************************************/ |
| |
| #ifndef SILK_TUNING_PARAMETERS_H |
| #define SILK_TUNING_PARAMETERS_H |
| |
| #ifdef __cplusplus |
| extern "C" |
| { |
| #endif |
| |
| /* Decay time for bitreservoir */ |
| #define BITRESERVOIR_DECAY_TIME_MS 500 |
| |
| /*******************/ |
| /* Pitch estimator */ |
| /*******************/ |
| |
| /* Level of noise floor for whitening filter LPC analysis in pitch analysis */ |
| #define FIND_PITCH_WHITE_NOISE_FRACTION 1e-3f |
| |
| /* Bandwidth expansion for whitening filter in pitch analysis */ |
| #define FIND_PITCH_BANDWIDTH_EXPANSION 0.99f |
| |
| /*********************/ |
| /* Linear prediction */ |
| /*********************/ |
| |
| /* LPC analysis regularization */ |
| #define FIND_LPC_COND_FAC 1e-5f |
| |
| /* Max cumulative LTP gain */ |
| #define MAX_SUM_LOG_GAIN_DB 250.0f |
| |
| /* LTP analysis defines */ |
| #define LTP_CORR_INV_MAX 0.03f |
| |
| /***********************/ |
| /* High pass filtering */ |
| /***********************/ |
| |
| /* Smoothing parameters for low end of pitch frequency range estimation */ |
| #define VARIABLE_HP_SMTH_COEF1 0.1f |
| #define VARIABLE_HP_SMTH_COEF2 0.015f |
| #define VARIABLE_HP_MAX_DELTA_FREQ 0.4f |
| |
| /* Min and max cut-off frequency values (-3 dB points) */ |
| #define VARIABLE_HP_MIN_CUTOFF_HZ 60 |
| #define VARIABLE_HP_MAX_CUTOFF_HZ 100 |
| |
| /***********/ |
| /* Various */ |
| /***********/ |
| |
| /* VAD threshold */ |
| #define SPEECH_ACTIVITY_DTX_THRES 0.05f |
| |
| /* Speech Activity LBRR enable threshold */ |
| #define LBRR_SPEECH_ACTIVITY_THRES 0.3f |
| |
| /*************************/ |
| /* Perceptual parameters */ |
| /*************************/ |
| |
| /* reduction in coding SNR during low speech activity */ |
| #define BG_SNR_DECR_dB 2.0f |
| |
| /* factor for reducing quantization noise during voiced speech */ |
| #define HARM_SNR_INCR_dB 2.0f |
| |
| /* factor for reducing quantization noise for unvoiced sparse signals */ |
| #define SPARSE_SNR_INCR_dB 2.0f |
| |
| /* threshold for sparseness measure above which to use lower quantization offset during unvoiced */ |
| #define ENERGY_VARIATION_THRESHOLD_QNT_OFFSET 0.6f |
| |
| /* warping control */ |
| #define WARPING_MULTIPLIER 0.015f |
| |
| /* fraction added to first autocorrelation value */ |
| #define SHAPE_WHITE_NOISE_FRACTION 3e-5f |
| |
| /* noise shaping filter chirp factor */ |
| #define BANDWIDTH_EXPANSION 0.94f |
| |
| /* harmonic noise shaping */ |
| #define HARMONIC_SHAPING 0.3f |
| |
| /* extra harmonic noise shaping for high bitrates or noisy input */ |
| #define HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING 0.2f |
| |
| /* parameter for shaping noise towards higher frequencies */ |
| #define HP_NOISE_COEF 0.25f |
| |
| /* parameter for shaping noise even more towards higher frequencies during voiced speech */ |
| #define HARM_HP_NOISE_COEF 0.35f |
| |
| /* parameter for applying a high-pass tilt to the input signal */ |
| #define INPUT_TILT 0.05f |
| |
| /* parameter for extra high-pass tilt to the input signal at high rates */ |
| #define HIGH_RATE_INPUT_TILT 0.1f |
| |
| /* parameter for reducing noise at the very low frequencies */ |
| #define LOW_FREQ_SHAPING 4.0f |
| |
| /* less reduction of noise at the very low frequencies for signals with low SNR at low frequencies */ |
| #define LOW_QUALITY_LOW_FREQ_SHAPING_DECR 0.5f |
| |
| /* subframe smoothing coefficient for HarmBoost, HarmShapeGain, Tilt (lower -> more smoothing) */ |
| #define SUBFR_SMTH_COEF 0.4f |
| |
| /* parameters defining the R/D tradeoff in the residual quantizer */ |
| #define LAMBDA_OFFSET 1.2f |
| #define LAMBDA_SPEECH_ACT -0.2f |
| #define LAMBDA_DELAYED_DECISIONS -0.05f |
| #define LAMBDA_INPUT_QUALITY -0.1f |
| #define LAMBDA_CODING_QUALITY -0.2f |
| #define LAMBDA_QUANT_OFFSET 0.8f |
| |
| /* Compensation in bitrate calculations for 10 ms modes */ |
| #define REDUCE_BITRATE_10_MS_BPS 2200 |
| |
| /* Maximum time before allowing a bandwidth transition */ |
| #define MAX_BANDWIDTH_SWITCH_DELAY_MS 5000 |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* SILK_TUNING_PARAMETERS_H */ |