libspeex/vbr.c - chromium/deps/speex - Git at Google

 /* Copyright (C) 2002 Jean-Marc Valin
    File: vbr.c

    VBR-related routines

    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 the Xiph.org Foundation nor the names of its
    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 FOUNDATION 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.

 */

 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif

 #include "vbr.h"
 #include <math.h>


 #define sqr(x) ((x)*(x))

 #define MIN_ENERGY 6000
 #define NOISE_POW .3

 #ifndef DISABLE_VBR

 const float vbr_nb_thresh[9][11]={
    {-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /*   CNG   */
    { 4.0f,  2.5f,  2.0f,  1.2f,  0.5f,  0.0f, -0.5f, -0.7f, -0.8f, -0.9f, -1.0f}, /*  2 kbps */
    {10.0f,  6.5f,  5.2f,  4.5f,  3.9f,  3.5f,  3.0f,  2.5f,  2.3f,  1.8f,  1.0f}, /*  6 kbps */
    {11.0f,  8.8f,  7.5f,  6.5f,  5.0f,  3.9f,  3.9f,  3.9f,  3.5f,  3.0f,  1.0f}, /*  8 kbps */
    {11.0f, 11.0f,  9.9f,  8.5f,  7.0f,  6.0f,  4.5f,  4.0f,  4.0f,  4.0f,  2.0f}, /* 11 kbps */
    {11.0f, 11.0f, 11.0f, 11.0f,  9.5f,  8.5f,  8.0f,  7.0f,  6.0f,  5.0f,  3.0f}, /* 15 kbps */
    {11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f,  9.5f,  8.5f,  7.0f,  6.0f,  5.0f}, /* 18 kbps */
    {11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f,  9.8f,  9.5f,  7.5f}, /* 24 kbps */
    { 7.0f,  4.5f,  3.7f,  3.0f,  2.5f,  2.0f,  1.8f,  1.5f,  1.0f,  0.0f,  0.0f}  /*  4 kbps */
 };


 const float vbr_hb_thresh[5][11]={
    {-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* silence */
    {-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /*  2 kbps */
    {11.0f, 11.0f,  9.5f,  8.5f,  7.5f,  6.0f,  5.0f,  3.9f,  3.0f,  2.0f,  1.0f}, /*  6 kbps */
    {11.0f, 11.0f, 11.0f, 11.0f, 11.0f,  9.5f,  8.7f,  7.8f,  7.0f,  6.5f,  4.0f}, /* 10 kbps */
    {11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f,  9.8f,  7.5f,  5.5f}  /* 18 kbps */
 };

 const float vbr_uhb_thresh[2][11]={
    {-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* silence */
    { 3.9f,  2.5f,  0.0f,  0.0f,  0.0f,  0.0f,  0.0f,  0.0f,  0.0f,  0.0f, -1.0f}  /*  2 kbps */
 };

 void vbr_init(VBRState *vbr)
 {
    int i;

    vbr->average_energy=0;
    vbr->last_energy=1;
    vbr->accum_sum=0;
    vbr->energy_alpha=.1;
    vbr->soft_pitch=0;
    vbr->last_pitch_coef=0;
    vbr->last_quality=0;

    vbr->noise_accum = .05*pow(MIN_ENERGY, NOISE_POW);
    vbr->noise_accum_count=.05;
    vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
    vbr->consec_noise=0;


    for (i=0;i<VBR_MEMORY_SIZE;i++)
       vbr->last_log_energy[i] = log(MIN_ENERGY);
 }


 /*
   This function should analyse the signal and decide how critical the
   coding error will be perceptually. The following factors should be
   taken into account:

   -Attacks (positive energy derivative) should be coded with more bits

   -Stationary voiced segments should receive more bits

   -Segments with (very) low absolute energy should receive less bits (maybe
   only shaped noise?)

   -DTX for near-zero energy?

   -Stationary fricative segments should have less bits

   -Temporal masking: when energy slope is decreasing, decrease the bit-rate

   -Decrease bit-rate for males (low pitch)?

   -(wideband only) less bits in the high-band when signal is very
   non-stationary (harder to notice high-frequency noise)???

 */

 float vbr_analysis(VBRState *vbr, spx_word16_t *sig, int len, int pitch, float pitch_coef)
 {
    int i;
    float ener=0, ener1=0, ener2=0;
    float qual=7;
    int va;
    float log_energy;
    float non_st=0;
    float voicing;
    float pow_ener;

    for (i=0;i<len>>1;i++)
       ener1 += ((float)sig[i])*sig[i];

    for (i=len>>1;i<len;i++)
       ener2 += ((float)sig[i])*sig[i];
    ener=ener1+ener2;

    log_energy = log(ener+MIN_ENERGY);
    for (i=0;i<VBR_MEMORY_SIZE;i++)
       non_st += sqr(log_energy-vbr->last_log_energy[i]);
    non_st =  non_st/(30*VBR_MEMORY_SIZE);
    if (non_st>1)
       non_st=1;

    voicing = 3*(pitch_coef-.4)*fabs(pitch_coef-.4);
    vbr->average_energy = (1-vbr->energy_alpha)*vbr->average_energy + vbr->energy_alpha*ener;
    vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
    pow_ener = pow(ener,NOISE_POW);
    if (vbr->noise_accum_count<.06 && ener>MIN_ENERGY)
       vbr->noise_accum = .05*pow_ener;

    if ((voicing<.3 && non_st < .2 && pow_ener < 1.2*vbr->noise_level)
        || (voicing<.3 && non_st < .05 && pow_ener < 1.5*vbr->noise_level)
        || (voicing<.4 && non_st < .05 && pow_ener < 1.2*vbr->noise_level)
        || (voicing<0 && non_st < .05))
    {
       float tmp;
       va = 0;
       vbr->consec_noise++;
       if (pow_ener > 3*vbr->noise_level)
          tmp = 3*vbr->noise_level;
       else
          tmp = pow_ener;
       if (vbr->consec_noise>=4)
       {
          vbr->noise_accum = .95*vbr->noise_accum + .05*tmp;
          vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
       }
    } else {
       va = 1;
       vbr->consec_noise=0;
    }

    if (pow_ener < vbr->noise_level && ener>MIN_ENERGY)
    {
       vbr->noise_accum = .95*vbr->noise_accum + .05*pow_ener;
       vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
    }

    /* Checking for very low absolute energy */
    if (ener < 30000)
    {
       qual -= .7;
       if (ener < 10000)
          qual-=.7;
       if (ener < 3000)
          qual-=.7;
    } else {
       float short_diff, long_diff;
       short_diff = log((ener+1)/(1+vbr->last_energy));
       long_diff = log((ener+1)/(1+vbr->average_energy));
       /*fprintf (stderr, "%f %f\n", short_diff, long_diff);*/

       if (long_diff<-5)
          long_diff=-5;
       if (long_diff>2)
          long_diff=2;

       if (long_diff>0)
          qual += .6*long_diff;
       if (long_diff<0)
          qual += .5*long_diff;
       if (short_diff>0)
       {
          if (short_diff>5)
             short_diff=5;
          qual += .5*short_diff;
       }
       /* Checking for energy increases */
       if (ener2 > 1.6*ener1)
          qual += .5;
    }
    vbr->last_energy = ener;
    vbr->soft_pitch = .6*vbr->soft_pitch + .4*pitch_coef;
    qual += 2.2*((pitch_coef-.4) + (vbr->soft_pitch-.4));

    if (qual < vbr->last_quality)
       qual = .5*qual + .5*vbr->last_quality;
    if (qual<4)
       qual=4;
    if (qual>10)
       qual=10;

    /*
    if (vbr->consec_noise>=2)
       qual-=1.3;
    if (vbr->consec_noise>=5)
       qual-=1.3;
    if (vbr->consec_noise>=12)
       qual-=1.3;
    */
    if (vbr->consec_noise>=3)
       qual=4;

    if (vbr->consec_noise)
       qual -= 1.0 * (log(3.0 + vbr->consec_noise)-log(3));
    if (qual<0)
       qual=0;

    if (ener<60000)
    {
       if (vbr->consec_noise>2)
          qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
       if (ener<10000&&vbr->consec_noise>2)
          qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
       if (qual<0)
          qual=0;
       qual += .3*log(.0001+ener/60000.0);
    }
    if (qual<-1)
       qual=-1;

    /*printf ("%f %f %f %f %d\n", qual, voicing, non_st, pow_ener/(.01+vbr->noise_level), va);*/

    vbr->last_pitch_coef = pitch_coef;
    vbr->last_quality = qual;

    for (i=VBR_MEMORY_SIZE-1;i>0;i--)
       vbr->last_log_energy[i] = vbr->last_log_energy[i-1];
    vbr->last_log_energy[0] = log_energy;

    /*printf ("VBR: %f %f %f %d %f\n", (float)(log_energy-log(vbr->average_energy+MIN_ENERGY)), non_st, voicing, va, vbr->noise_level);*/

    return qual;
 }

 void vbr_destroy(VBRState *vbr)
 {
 }

 #endif /* #ifndef DISABLE_VBR */
	/* Copyright (C) 2002 Jean-Marc Valin
	File: vbr.c

	VBR-related routines

	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 the Xiph.org Foundation nor the names of its
	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 FOUNDATION 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.

	*/

	#ifdef HAVE_CONFIG_H
	#include "config.h"
	#endif

	#include "vbr.h"
	#include <math.h>


	#define sqr(x) ((x)*(x))

	#define MIN_ENERGY 6000
	#define NOISE_POW .3

	#ifndef DISABLE_VBR

	const float vbr_nb_thresh[9][11]={
	{-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* CNG */
	{ 4.0f, 2.5f, 2.0f, 1.2f, 0.5f, 0.0f, -0.5f, -0.7f, -0.8f, -0.9f, -1.0f}, /* 2 kbps */
	{10.0f, 6.5f, 5.2f, 4.5f, 3.9f, 3.5f, 3.0f, 2.5f, 2.3f, 1.8f, 1.0f}, /* 6 kbps */
	{11.0f, 8.8f, 7.5f, 6.5f, 5.0f, 3.9f, 3.9f, 3.9f, 3.5f, 3.0f, 1.0f}, /* 8 kbps */
	{11.0f, 11.0f, 9.9f, 8.5f, 7.0f, 6.0f, 4.5f, 4.0f, 4.0f, 4.0f, 2.0f}, /* 11 kbps */
	{11.0f, 11.0f, 11.0f, 11.0f, 9.5f, 8.5f, 8.0f, 7.0f, 6.0f, 5.0f, 3.0f}, /* 15 kbps */
	{11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 9.5f, 8.5f, 7.0f, 6.0f, 5.0f}, /* 18 kbps */
	{11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 9.8f, 9.5f, 7.5f}, /* 24 kbps */
	{ 7.0f, 4.5f, 3.7f, 3.0f, 2.5f, 2.0f, 1.8f, 1.5f, 1.0f, 0.0f, 0.0f} /* 4 kbps */
	};


	const float vbr_hb_thresh[5][11]={
	{-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* silence */
	{-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* 2 kbps */
	{11.0f, 11.0f, 9.5f, 8.5f, 7.5f, 6.0f, 5.0f, 3.9f, 3.0f, 2.0f, 1.0f}, /* 6 kbps */
	{11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 9.5f, 8.7f, 7.8f, 7.0f, 6.5f, 4.0f}, /* 10 kbps */
	{11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 11.0f, 9.8f, 7.5f, 5.5f} /* 18 kbps */
	};

	const float vbr_uhb_thresh[2][11]={
	{-1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f, -1.0f}, /* silence */
	{ 3.9f, 2.5f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f} /* 2 kbps */
	};

	void vbr_init(VBRState *vbr)
	{
	int i;

	vbr->average_energy=0;
	vbr->last_energy=1;
	vbr->accum_sum=0;
	vbr->energy_alpha=.1;
	vbr->soft_pitch=0;
	vbr->last_pitch_coef=0;
	vbr->last_quality=0;

	vbr->noise_accum = .05*pow(MIN_ENERGY, NOISE_POW);
	vbr->noise_accum_count=.05;
	vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
	vbr->consec_noise=0;


	for (i=0;i<VBR_MEMORY_SIZE;i++)
	vbr->last_log_energy[i] = log(MIN_ENERGY);
	}


	/*
	This function should analyse the signal and decide how critical the
	coding error will be perceptually. The following factors should be
	taken into account:

	-Attacks (positive energy derivative) should be coded with more bits

	-Stationary voiced segments should receive more bits

	-Segments with (very) low absolute energy should receive less bits (maybe
	only shaped noise?)

	-DTX for near-zero energy?

	-Stationary fricative segments should have less bits

	-Temporal masking: when energy slope is decreasing, decrease the bit-rate

	-Decrease bit-rate for males (low pitch)?

	-(wideband only) less bits in the high-band when signal is very
	non-stationary (harder to notice high-frequency noise)???

	*/

	float vbr_analysis(VBRState vbr, spx_word16_t sig, int len, int pitch, float pitch_coef)
	{
	int i;
	float ener=0, ener1=0, ener2=0;
	float qual=7;
	int va;
	float log_energy;
	float non_st=0;
	float voicing;
	float pow_ener;

	for (i=0;i<len>>1;i++)
	ener1 += ((float)sig[i])*sig[i];

	for (i=len>>1;i<len;i++)
	ener2 += ((float)sig[i])*sig[i];
	ener=ener1+ener2;

	log_energy = log(ener+MIN_ENERGY);
	for (i=0;i<VBR_MEMORY_SIZE;i++)
	non_st += sqr(log_energy-vbr->last_log_energy[i]);
	non_st = non_st/(30*VBR_MEMORY_SIZE);
	if (non_st>1)
	non_st=1;

	voicing = 3(pitch_coef-.4)fabs(pitch_coef-.4);
	vbr->average_energy = (1-vbr->energy_alpha)vbr->average_energy + vbr->energy_alphaener;
	vbr->noise_level=vbr->noise_accum/vbr->noise_accum_count;
	pow_ener = pow(ener,NOISE_POW);
	if (vbr->noise_accum_count<.06 && ener>MIN_ENERGY)
	vbr->noise_accum = .05*pow_ener;

	if ((voicing<.3 && non_st < .2 && pow_ener < 1.2*vbr->noise_level)
	\|\| (voicing<.3 && non_st < .05 && pow_ener < 1.5*vbr->noise_level)
	\|\| (voicing<.4 && non_st < .05 && pow_ener < 1.2*vbr->noise_level)
	\|\| (voicing<0 && non_st < .05))
	{
	float tmp;
	va = 0;
	vbr->consec_noise++;
	if (pow_ener > 3*vbr->noise_level)
	tmp = 3*vbr->noise_level;
	else
	tmp = pow_ener;
	if (vbr->consec_noise>=4)
	{
	vbr->noise_accum = .95vbr->noise_accum + .05tmp;
	vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
	}
	} else {
	va = 1;
	vbr->consec_noise=0;
	}

	if (pow_ener < vbr->noise_level && ener>MIN_ENERGY)
	{
	vbr->noise_accum = .95vbr->noise_accum + .05pow_ener;
	vbr->noise_accum_count = .95*vbr->noise_accum_count + .05;
	}

	/* Checking for very low absolute energy */
	if (ener < 30000)
	{
	qual -= .7;
	if (ener < 10000)
	qual-=.7;
	if (ener < 3000)
	qual-=.7;
	} else {
	float short_diff, long_diff;
	short_diff = log((ener+1)/(1+vbr->last_energy));
	long_diff = log((ener+1)/(1+vbr->average_energy));
	/fprintf (stderr, "%f %f\n", short_diff, long_diff);/

	if (long_diff<-5)
	long_diff=-5;
	if (long_diff>2)
	long_diff=2;

	if (long_diff>0)
	qual += .6*long_diff;
	if (long_diff<0)
	qual += .5*long_diff;
	if (short_diff>0)
	{
	if (short_diff>5)
	short_diff=5;
	qual += .5*short_diff;
	}
	/* Checking for energy increases */
	if (ener2 > 1.6*ener1)
	qual += .5;
	}
	vbr->last_energy = ener;
	vbr->soft_pitch = .6vbr->soft_pitch + .4pitch_coef;
	qual += 2.2*((pitch_coef-.4) + (vbr->soft_pitch-.4));

	if (qual < vbr->last_quality)
	qual = .5qual + .5vbr->last_quality;
	if (qual<4)
	qual=4;
	if (qual>10)
	qual=10;

	/*
	if (vbr->consec_noise>=2)
	qual-=1.3;
	if (vbr->consec_noise>=5)
	qual-=1.3;
	if (vbr->consec_noise>=12)
	qual-=1.3;
	*/
	if (vbr->consec_noise>=3)
	qual=4;

	if (vbr->consec_noise)
	qual -= 1.0 * (log(3.0 + vbr->consec_noise)-log(3));
	if (qual<0)
	qual=0;

	if (ener<60000)
	{
	if (vbr->consec_noise>2)
	qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
	if (ener<10000&&vbr->consec_noise>2)
	qual-=0.5*(log(3.0 + vbr->consec_noise)-log(3));
	if (qual<0)
	qual=0;
	qual += .3*log(.0001+ener/60000.0);
	}
	if (qual<-1)
	qual=-1;

	/printf ("%f %f %f %f %d\n", qual, voicing, non_st, pow_ener/(.01+vbr->noise_level), va);/

	vbr->last_pitch_coef = pitch_coef;
	vbr->last_quality = qual;

	for (i=VBR_MEMORY_SIZE-1;i>0;i--)
	vbr->last_log_energy[i] = vbr->last_log_energy[i-1];
	vbr->last_log_energy[0] = log_energy;

	/printf ("VBR: %f %f %f %d %f\n", (float)(log_energy-log(vbr->average_energy+MIN_ENERGY)), non_st, voicing, va, vbr->noise_level);/

	return qual;
	}

	void vbr_destroy(VBRState *vbr)
	{
	}

	#endif /* #ifndef DISABLE_VBR */