s_util.h

关于AMR-WB+语音压缩编码的实现代码

/* Stereo utilities */

#ifndef STEREO_UTIL_H
#define STEREO_UTIL_H
#include "cnst.h"
#include "mem.h"            // needed for definition of "Coder_State_Plus"
#include "options.h"

float my_max(float x, float y);
float my_min(float x, float y);

void crosscorrVA(float *x,      /* input : input signal */
                 float *y, float *r,    /* output: autocorrelations vector */
                 int m,         /* input : order of LP filter */
                 int n,         /* input : window size */
                 float *fh      /* input : analysis window */
    );

void fir_filt(float *h,         /* input : filter coefficients */
              int m,            /* input : order of filter */
              float *x,         /* input : input signal (usually mono) */
              float *y,         /* output: output signal (usually stereo) */
              int l             /* input : size of filtering */
    );

void int_fir(float fir_old[],   /* input : FIR from past frame */
             float fir_new[],   /* input : FIR from present frame */
             float h[],         /* output: FIR coefficients in both subframes */
             int nb_subfr,      /* input: number of subframe */
             int m              /* input : order of FIR filter */
    );

void mix_ch(float *ch_left,     /* input: samples from left channel */
            float *ch_right,    /* input: samples from right channel */
            float *ch_sum,      /* output: mixed mono signal */
            int n,              /* input: length of frame */
            float gA,           /* input: weight factor for left channel */
            float gB            /* input: weight factor for right channel */
    );

#ifndef CLEAN_UP_VCC_WARN
#ifdef COSINE_INTERP
void init_csbi_window(void);
#endif
#ifdef LAGW
void init_lag_wind_su(float lag_window[], float bwe,    /* input : bandwidth expansion */
                      float f_samp,     /* input : sampling frequency */
                      float wnc,        /* input : white noise correction factor */
                      int m     /* input : order of LP filter */
    );
#endif

#ifdef LAGW
void lag_wind_s(float lag_window[], float rcc[], float rca[], float rcb[], int m);
void lag_wind_s2(float lag_window[], float rcc[], float rca[], int m);

#else
void init_lag_wind_s(float bwe, float f_samp, float wnc, int m);

void lag_wind_s(float r[], int m);

#endif
#endif

int chol(int order,             /* (i) : Order */
         float *a, float *c, float *b);

/*-------------------------------------------------------------------*
 * Function  band_split												 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~										 *
 *   ->	Routine for splitting one frame into one high-frequency part *	
 *		and one low-frequency part.									 *
 *-------------------------------------------------------------------*/

void band_split(float *x_fb,    /* (i) : Full-band samples */
                float *x_hb,    /* (o) : Hi-band samples */
                float *x_lb,    /* (o) : Low-band samples */
                float *h,       /* (i) : Filter coefficients */
                int ncoeff      /* (i) : Number of filter coefficients */
    );

void band_split_2k(float sig[], float sig_2k[], float sig_hi[], int lg, float mem_sig[], float mem_sig_2k[]);

void band_split_taligned_2k(float sig[], float sig_2k[], float sig_hi[], int lg);

/*-------------------------------------------------------------------*
 * Function  band_join												 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~										 *
 *   ->	Routine for joining one high-frequency part					 *	
 *		and one low-frequency part into one frame.					 *
 *-------------------------------------------------------------------*/

void band_join_2k(float sig[], float sig_2k[], float sig_hi[], int lg);

void gen_chan(float *ac,        /* (i) : filter coefficients */
              float *c,         /* (i) : Mixed channel */
              float *a,         /* (o) : Left channel */
              float *b,         /* (o) : Right channel */
              int band_2k       /* (i) : Operation in low band */
    );

void write_wave_header(FILE * fp, int srate, int nCh, int size);

/* Mix channels with prefiltering for sum channel*/
void mix_ch_pf(float *ch_left,  /* input: samples from left channel */
               float *ch_right, /* input: samples from right channel */
               float *ch_sum,   /* output: mixed mono signal */
               float *ch_sum_pf,        /* output: mixed mono signal, prefiltered */
               Coder_State_Plus * st);       /* i/o : coder memory state */

#endif