www.pudn.com > AVS_M_ver10.rar > tcx_ecu.c

/* 
*********************************************************************** 
* COPYRIGHT AND WARRANTY INFORMATION 
* 
* Copyright 2007  Audio Video Coding Standard, Part ¢ú 
* 
* This software module was developed by AVS Audio sub-group 
* 
* DISCLAIMER OF WARRANTY 
* 
* These software programs are available to the users without any 
* license fee or royalty on an "as is" basis. The AVS disclaims 
* any and all warranties, whether express, implied, or statutory, 
* including any implied warranties of merchantability or of fitness 
* for a particular purpose. In no event shall the contributors or  
* the AVS be liable for any incidental, punitive, or consequential 
* damages of any kind whatsoever arising from the use of this program. 
* 
* This disclaimer of warranty extends to the user of this program 
* and user's customers, employees, agents, transferees, successors, 
* and assigns. 
* 
* The AVS does not represent or warrant that the program furnished 
* hereunder are free of infringement of any third-party patents. 
* Commercial implementations of AVS, including shareware, may be 
* subject to royalty fees to patent holders. Information regarding 
* the AVS patent policy is available from the AVS Web site at 
* http://www.avs.org.cn 
* 
* THIS IS NOT A GRANT OF PATENT RIGHTS - SEE THE AVS PATENT POLICY. 
************************************************************************ 
*/ 
 
#include  
#include  
#include  
#include  
#include "../include/amr_plus.h" 
/* 
	phasor computations 
*/ 
void get_phasor(float xri[],float ph[]) 
{ 
	float tmp = 0.0; 
	tmp = xri[0]*xri[0] + xri[1]*xri[1]; 
	if(tmp == 0.0f) { 
		ph[0] = 1; 
		ph[1] = 0; 
	} 
	else { 
		tmp = 1.0f/(float) sqrt(tmp); 
		ph[0] = xri[0] * tmp; 
		ph[1] = xri[1] * tmp; 
	} 
} 
void mult_phasor(float ph1[],float ph2[],float res[]) 
{ 
	float ph_re,ph_im; 
	ph_re = ph1[0]*ph2[0] - ph1[1]* ph2[1]; 
	ph_im = ph1[1]*ph2[0] + ph1[0]* ph2[1]; 
	res[0] = ph_re; 
	res[1] = ph_im; 
} 
void div_phasor(float ph1[],float ph2[],float res[]) 
{ 
	float ph_re,ph_im; 
	ph_re = ph1[0]*ph2[0] + ph1[1]* ph2[1]; 
	ph_im = ph1[1]*ph2[0] - ph1[0]* ph2[1]; 
	res[0] = ph_re; 
	res[1] = ph_im; 
}	 
/*---------------------------------------------------------------*/ 
/* Adaptive low frequency de-emphasis in case of packet loss	 */ 
/*																 */ 
/*																 */ 
/*---------------------------------------------------------------*/ 
void adapt_low_freq_deemph_ecu(float xri[], 
			       int lg,   
			       Decoder_State_Plus *st) 
{ 
	int i,j; 
	float buf[L_TCX/4]; 
	float max,fac,tmp; 
	float pred_max; 
	int curr_mode=3; 
	/*---------------------------------------------------------------* 
	* Set correct buffer lengths  								    * 
	*---------------------------------------------------------------*/ 
	if(lg == 1152) {curr_mode =3;} 
	if(lg == 576)  {curr_mode =2;} 
	if(lg == 288)  {curr_mode =1;} 
	if((st->last_mode != curr_mode) || (curr_mode <= 2))  
	{ 
		pred_max = 0.0f; 
	} 
	else  
	{ 
		/*---------------------------------------------------------------* 
		* Temporary working buffer									    * 
		*---------------------------------------------------------------*/ 
		mvr2r(st->old_xri,buf,lg/4); 
		/*---------------------------------------------------------------* 
		* Find spectral peak under 1600Hz (lg = 6400Hz)                 * 
		* (find maximum of energy of all Re8 subvector under 1600Hz)    * 
		*---------------------------------------------------------------*/ 
		max = 0.01f; 
		for(i=0; i max)  
			{	 
				max = tmp; 
			} 
		} 
		pred_max = (float)sqrt(max);       /* sqrt of energy */ 
	} 
   /*---------------------------------------------------------------* 
	* Find spectral peak under 1600Hz (lg = 6400Hz)                 * 
	* (find maximum of energy of all Re8 subvector under 1600Hz)    * 
	*---------------------------------------------------------------*/ 
	max = 0.01f; 
	for(i=0; i max)  
		{ 
			max = tmp; 
		} 
	} 
	max = (float)sqrt(max);       /* sqrt of energy */ 
	/*---------------------------------------------------------------*/ 
	/* Set the new max												 */ 
	/*---------------------------------------------------------------*/ 
	if(max < pred_max)  
	{ 
		max = pred_max; 
	} 
   /*---------------------------------------------------------------* 
	* Deemphasis of all subvector below 1600 Hz.                    * 
	*---------------------------------------------------------------*/ 
	fac = 0.1f; 
	for(i=0; i fac)  
		{ 
			fac = tmp; 
		} 
		for(j=i; j 0.0f)  
		{ 
			energy += sp[i]; 
			old_energy += old_sp[i]; 
		} 
	} 
	gain_sq = energy / old_energy;	pessimize(); 
	gain = (float)sqrt(gain_sq); 
	/* limit the gain */ 
	if(gain >1.4142f) { 
		gain = 1.4142f; 
		gain_sq = 2.0f; 
	} 
	/*---------------------------------------------------------------* 
	* merge with the new spectrum									* 
	*---------------------------------------------------------------*/ 
	for(i=0;i