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      1 /*
      2  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
      3  *
      4  *  Use of this source code is governed by a BSD-style license
      5  *  that can be found in the LICENSE file in the root of the source
      6  *  tree. An additional intellectual property rights grant can be found
      7  *  in the file PATENTS.  All contributing project authors may
      8  *  be found in the AUTHORS file in the root of the source tree.
      9  */
     10 
     11 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_NS_MAIN_SOURCE_NS_CORE_H_
     12 #define WEBRTC_MODULES_AUDIO_PROCESSING_NS_MAIN_SOURCE_NS_CORE_H_
     13 
     14 #include "defines.h"
     15 
     16 typedef struct NSParaExtract_t_ {
     17 
     18   //bin size of histogram
     19   float binSizeLrt;
     20   float binSizeSpecFlat;
     21   float binSizeSpecDiff;
     22   //range of histogram over which lrt threshold is computed
     23   float rangeAvgHistLrt;
     24   //scale parameters: multiply dominant peaks of the histograms by scale factor to obtain
     25   //thresholds for prior model
     26   float factor1ModelPars; //for lrt and spectral difference
     27   float factor2ModelPars; //for spectral_flatness: used when noise is flatter than speech
     28   //peak limit for spectral flatness (varies between 0 and 1)
     29   float thresPosSpecFlat;
     30   //limit on spacing of two highest peaks in histogram: spacing determined by bin size
     31   float limitPeakSpacingSpecFlat;
     32   float limitPeakSpacingSpecDiff;
     33   //limit on relevance of second peak:
     34   float limitPeakWeightsSpecFlat;
     35   float limitPeakWeightsSpecDiff;
     36   //limit on fluctuation of lrt feature
     37   float thresFluctLrt;
     38   //limit on the max and min values for the feature thresholds
     39   float maxLrt;
     40   float minLrt;
     41   float maxSpecFlat;
     42   float minSpecFlat;
     43   float maxSpecDiff;
     44   float minSpecDiff;
     45   //criteria of weight of histogram peak  to accept/reject feature
     46   int thresWeightSpecFlat;
     47   int thresWeightSpecDiff;
     48 
     49 } NSParaExtract_t;
     50 
     51 typedef struct NSinst_t_ {
     52 
     53   WebRtc_UWord32  fs;
     54   int             blockLen;
     55   int             blockLen10ms;
     56   int             windShift;
     57   int             outLen;
     58   int             anaLen;
     59   int             magnLen;
     60   int             aggrMode;
     61   const float*    window;
     62   float           dataBuf[ANAL_BLOCKL_MAX];
     63   float           syntBuf[ANAL_BLOCKL_MAX];
     64   float           outBuf[3 * BLOCKL_MAX];
     65 
     66   int             initFlag;
     67   // parameters for quantile noise estimation
     68   float           density[SIMULT* HALF_ANAL_BLOCKL];
     69   float           lquantile[SIMULT* HALF_ANAL_BLOCKL];
     70   float           quantile[HALF_ANAL_BLOCKL];
     71   int             counter[SIMULT];
     72   int             updates;
     73   // parameters for Wiener filter
     74   float           smooth[HALF_ANAL_BLOCKL];
     75   float           overdrive;
     76   float           denoiseBound;
     77   int             gainmap;
     78   // fft work arrays.
     79   int             ip[IP_LENGTH];
     80   float           wfft[W_LENGTH];
     81 
     82   // parameters for new method: some not needed, will reduce/cleanup later
     83   WebRtc_Word32   blockInd;                           //frame index counter
     84   int             modelUpdatePars[4];                 //parameters for updating or estimating
     85   // thresholds/weights for prior model
     86   float           priorModelPars[7];                  //parameters for prior model
     87   float           noisePrev[HALF_ANAL_BLOCKL];        //noise spectrum from previous frame
     88   float           magnPrev[HALF_ANAL_BLOCKL];         //magnitude spectrum of previous frame
     89   float           logLrtTimeAvg[HALF_ANAL_BLOCKL];    //log lrt factor with time-smoothing
     90   float           priorSpeechProb;                    //prior speech/noise probability
     91   float           featureData[7];                     //data for features
     92   float           magnAvgPause[HALF_ANAL_BLOCKL];     //conservative noise spectrum estimate
     93   float           signalEnergy;                       //energy of magn
     94   float           sumMagn;                            //sum of magn
     95   float           whiteNoiseLevel;                    //initial noise estimate
     96   float           initMagnEst[HALF_ANAL_BLOCKL];      //initial magnitude spectrum estimate
     97   float           pinkNoiseNumerator;                 //pink noise parameter: numerator
     98   float           pinkNoiseExp;                       //pink noise parameter: power of freq
     99   NSParaExtract_t featureExtractionParams;            //parameters for feature extraction
    100   //histograms for parameter estimation
    101   int             histLrt[HIST_PAR_EST];
    102   int             histSpecFlat[HIST_PAR_EST];
    103   int             histSpecDiff[HIST_PAR_EST];
    104   //quantities for high band estimate
    105   float           speechProbHB[HALF_ANAL_BLOCKL];     //final speech/noise prob: prior + LRT
    106   float           dataBufHB[ANAL_BLOCKL_MAX];         //buffering data for HB
    107 
    108 } NSinst_t;
    109 
    110 
    111 #ifdef __cplusplus
    112 extern "C" {
    113 #endif
    114 
    115 /****************************************************************************
    116  * WebRtcNs_InitCore(...)
    117  *
    118  * This function initializes a noise suppression instance
    119  *
    120  * Input:
    121  *      - inst          : Instance that should be initialized
    122  *      - fs            : Sampling frequency
    123  *
    124  * Output:
    125  *      - inst          : Initialized instance
    126  *
    127  * Return value         :  0 - Ok
    128  *                        -1 - Error
    129  */
    130 int WebRtcNs_InitCore(NSinst_t* inst, WebRtc_UWord32 fs);
    131 
    132 /****************************************************************************
    133  * WebRtcNs_set_policy_core(...)
    134  *
    135  * This changes the aggressiveness of the noise suppression method.
    136  *
    137  * Input:
    138  *      - inst          : Instance that should be initialized
    139  *      - mode          : 0: Mild (6 dB), 1: Medium (10 dB), 2: Aggressive (15 dB)
    140  *
    141  * Output:
    142  *      - NS_inst      : Initialized instance
    143  *
    144  * Return value         :  0 - Ok
    145  *                        -1 - Error
    146  */
    147 int WebRtcNs_set_policy_core(NSinst_t* inst, int mode);
    148 
    149 /****************************************************************************
    150  * WebRtcNs_ProcessCore
    151  *
    152  * Do noise suppression.
    153  *
    154  * Input:
    155  *      - inst          : Instance that should be initialized
    156  *      - inFrameLow    : Input speech frame for lower band
    157  *      - inFrameHigh   : Input speech frame for higher band
    158  *
    159  * Output:
    160  *      - inst          : Updated instance
    161  *      - outFrameLow   : Output speech frame for lower band
    162  *      - outFrameHigh  : Output speech frame for higher band
    163  *
    164  * Return value         :  0 - OK
    165  *                        -1 - Error
    166  */
    167 
    168 
    169 int WebRtcNs_ProcessCore(NSinst_t* inst,
    170                          short* inFrameLow,
    171                          short* inFrameHigh,
    172                          short* outFrameLow,
    173                          short* outFrameHigh);
    174 
    175 
    176 #ifdef __cplusplus
    177 }
    178 #endif
    179 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_NS_MAIN_SOURCE_NS_CORE_H_
    180