gtagc32.c

ARM平台下的数字音频AGC处理源代码 采用EP9302,对数字音频进行AGC处理

#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <math.h>
#include <malloc.h>


#include "GtAGC32.h"

/*三个电平值参数,以dB计算, */
GtAGC* NewGtagc(int peek_level, int  dynamic_threshold, int noise_threshold, int inputmode)
{
    GtAGC *agc = malloc(sizeof(GtAGC));

    if(agc == NULL)
    {
        return NULL;
    }
	SetGtagc(agc, peek_level, dynamic_threshold, noise_threshold,inputmode);
    return agc;
}

//设置AGC参数
int SetGtagc(GtAGC *agc, int peek_level, int  dynamic_threshold, int noise_threshold, int inputmode)
{
	int peak, dynamic, noise;

    if(agc == NULL)
    {
        return -1;
    }
	agc->sample_max[0]=1;
	agc->sample_max[1]=1;
  	agc->pre_max[0] = 1;
	agc->pre_max[1] = 1;
	agc->post_max[0] =1;
	agc->post_max[1] =1;

        agc->pre_max1[0] = 1;
	agc->pre_max1[1] = 1;
	agc->post_max1[0] =1;
	agc->post_max1[1] =1;


	agc->pre_sum[0] = 1;
	agc->pre_sum[1] = 1;
	agc->post_sum[0] =1;
	agc->post_sum[1] =1;

	agc->gain[0] = 1.0f;
	agc->gain[1] = 1.0f;
	
	agc->silence_counter[0] = 0;
	agc->silence_counter[1] = 0;

	agc->counter[0] = 0;	
	agc->counter[1] = 0;
    
	/*
	if(peek_level>-3)peek_level=-3;
	else if(peek_level<-20)peek_level=-20;
	
	if( dynamic_threshold > peek_level ) dynamic_threshold=peek_level;
	else if( dynamic_threshold < (peek_level-20) ) dynamic_threshold=peek_level-20;

	if( noise_threshold > (dynamic_threshold -10) ) noise_threshold= dynamic_threshold -10;
	*/
		peak   = REF_0dB  * pow( 10, ( (float)peek_level / 20.0 ) )/10;
		dynamic= REF_0dB * pow( 10, ( (float) dynamic_threshold / 20.0) )/10;
		noise  = REF_0dB * pow( 10, ( (float) noise_threshold / 20.0) )/10;
	
	printf("parameter:%d %d,%d,%d .\n",REF_0dB, peek_level, dynamic_threshold, noise_threshold );
    agc->peak = peak;
	printf("agc->peak:%ld\n",agc->peak);   
	
	//第二个门限
	agc->active_threshold = dynamic;
	printf("agc->active_theshold:%ld\n",agc->active_threshold);  

	agc->silence_threshold = noise;
	printf("agc->silence_threshold:%ld\n",agc->silence_threshold);  
	
	agc->pk=(float)(agc->peak - agc->active_threshold) / (MAX24bit - agc->silence_threshold);

    return 1;
}

void DeleteGtagc(GtAGC *agc)
{
    free(agc);
}


void DoGtagc(GtAGC *agc, long *buffer, int len, int volume, int bpcount,int adaes3)
{
    int i;
	float gain_new[2];
    long sample,sample1;
	int	index;
	agc->pre_max[0]  =1;
	agc->pre_max[1]  =1;
	agc->post_max[0] =1;
	agc->post_max[1] =1;
	agc->pre_sum[0]  =1;
	agc->pre_sum[1]  =1;
	agc->post_sum[0] =1;
	agc->post_sum[1] =1;

	agc->pre_max1[0]  =1;
	agc->pre_max1[1]  =1;
	agc->post_max1[0] =1;
	agc->post_max1[1] =1;

	
	for(i=0;i<len;i++)
    {
        

		index=i&0x00000001;
		//由24bit转化为32bit, 特别注意正负符号
		
		buffer[i]=( buffer[i] >= MAX24bit ? (buffer[i] | 0xff000000) : buffer[i]);
		sample = buffer[i];        
		sample = (sample < 0 ? -(sample):sample);

        if(sample > (long)agc->sample_max[index])
        {
            agc->sample_max[index] = (long)sample;
        }

		if(sample > (long)agc->pre_max[index])
        {
            agc->pre_max[index] = (long)sample;
        }
		agc->pre_sum[index] += sample;//*sample;
       agc->counter[index] ++;

        //attack
        if ((float)sample * agc->gain[index] > agc->peak)
        {
            agc->gain[index] = (float)(agc->peak / (float) agc->sample_max[index]) * 0.95f;
            agc->silence_counter[index] = 0;
            buffer[i] = (long) (buffer[i] * agc->gain[index]);
            continue;
        }
		
		

		if (agc->counter[index] >= 1024*2) 
        {
			
			//release
			if ((long)(agc->sample_max[index]) > agc->silence_threshold) //下限二
			{
				 gain_new[index] = 0.95 * ( (float) (agc->pk) * (agc->sample_max[index] - \
							agc->silence_threshold) + agc->active_threshold ) / \
							( (float) (agc->sample_max[index]) );
				
                
				if (agc->silence_counter[index] > 40) 
					agc->gain[index] += (gain_new[index] - agc->gain[index]) * 0.5f;
				else
					agc->gain[index] += (gain_new[index] - agc->gain[index]) * 0.1f;

				agc->silence_counter[index] = 0;
			}
			else
			{
				agc->silence_counter[index]++;	                	
				if ((agc->gain[index] > 1.0f) && (agc->silence_counter >= 20))
              	agc->gain[index] *= 0.8f; 
           	}
          	agc->counter[index] = 0;   
			agc->sample_max[index] = 1;
		}//end if 

		buffer[i] = (long) (buffer[i] * agc->gain[index]);

		//sample = buffer[i]; 
		
	
	/*buffer[i]=buffer[i]*bpcount/100;*/
		
		sample = buffer[i];
		
		sample = (sample < 0 ? -(sample):sample);

		if(sample > (long)agc->post_max[index])
        {
            agc->post_max[index] = (long)sample;
        }
		agc->post_sum[index] += sample;//*sample;
    }//end for
	for(i=0;i<len;i++)
	{
		

		index=i&0x00000001;
		//由24bit转化为32bit, 特别注意正负符号
		
		buffer[i]=( buffer[i] >= MAX24bit ? (buffer[i] | 0xff000000) : buffer[i]);
	
		sample1 = buffer[i];        
		sample1 = (sample1 < 0 ? -(sample1):sample1);

        if(sample1 > (long)agc->sample_max[index])
        {
            agc->sample_max[index] = (long)sample1;
        }

		if(sample1 > (long)agc->pre_max1[index])
        {
            agc->pre_max1[index] = (long)sample1;
        }
	

		if(volume==80) buffer[i]=0x00000000;
		else if(volume== 20) buffer[i]=buffer[i]*0.1;
		else if(volume== 1) buffer[i]=buffer[i]*0.9;
		else if(volume== 2) buffer[i]=buffer[i]*0.8;
		else if(volume== 3) buffer[i]=buffer[i]*0.7;
		else if(volume== 4) buffer[i]=buffer[i]*0.63;
		else if(volume== 5) buffer[i]=buffer[i]*0.56;
		else if(volume== 6) buffer[i]=buffer[i]*0.5;
		else if(volume== 7) buffer[i]=buffer[i]*0.45;
		else if(volume== 8) buffer[i]=buffer[i]*0.4;
		else if(volume== 9) buffer[i]=buffer[i]*0.35;
		else if(volume== 10) buffer[i]=buffer[i]*0.31;
		else if(volume== 11) buffer[i]=buffer[i]*0.28;
		else if(volume== 12) buffer[i]=buffer[i]*0.25;
		else if(volume== 13) buffer[i]=buffer[i]*0.22;
		else if(volume== 14) buffer[i]=buffer[i]*0.2;
		else if(volume== 15) buffer[i]=buffer[i]*0.18;
		else if(volume== 16) buffer[i]=buffer[i]*0.16;
		else if(volume== 17) buffer[i]=buffer[i]*0.14;
		else if(volume== 18) buffer[i]=buffer[i]*0.13;
		else if(volume== 19) buffer[i]=buffer[i]*0.11;
		else if(volume== 0) buffer[i]=buffer[i];
		if(bpcount<10000&adaes3==0) buffer[i]=0x00000000;

	sample1 = buffer[i];
		
		sample1 = (sample1 < 0 ? -(sample1):sample1);

		if(sample1 > (long)agc->post_max1[index])
        {
            agc->post_max1[index] = (long)sample1;
        }
	}
	bpcount++;
	if(bpcount<=10000&adaes3==1) buffer[i]=0;

	
    return;
}