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#include "pcm_utils.h"
#include "mpd_types.h"
#include "log.h"
#include <string.h>
#include <math.h>
void pcm_changeBufferEndianness(char * buffer, int bufferSize, int bits) {
char temp;
switch(bits) {
case 16:
while(bufferSize) {
temp = *buffer;
*buffer = *(buffer+1);
*(buffer+1) = temp;
bufferSize-=2;
}
break;
}
}
void pcm_volumeChange(char * buffer, int bufferSize, AudioFormat * format,
int volume)
{
mpd_sint32 temp32;
mpd_sint8 * buffer8 = (mpd_sint8 *)buffer;
mpd_sint16 * buffer16 = (mpd_sint16 *)buffer;
if(volume>=100) return;
if(volume<=0) {
memset(buffer,0,bufferSize);
return;
}
switch(format->bits) {
case 16:
while(bufferSize>0) {
temp32 = *buffer16;
temp32*= volume;
temp32/=100;
*buffer16 = temp32>32767 ? 32767 :
(temp32<-32768 ? -32768 : temp32);
buffer16++;
bufferSize-=2;
}
break;
case 8:
while(bufferSize>0) {
temp32 = *buffer8;
temp32*= volume;
temp32/=100;
*buffer8 = temp32>127 ? 127 :
(temp32<-128 ? -128 : temp32);
buffer8++;
bufferSize--;
}
break;
default:
ERROR("%i bits not supported by pcm_volumeChange!\n",
format->bits);
exit(-1);
}
}
void pcm_add(char * buffer1, char * buffer2, size_t bufferSize1,
size_t bufferSize2, AudioFormat * format)
{
mpd_sint32 temp32;
mpd_sint8 * buffer8_1 = (mpd_sint8 *)buffer1;
mpd_sint8 * buffer8_2 = (mpd_sint8 *)buffer2;
mpd_sint16 * buffer16_1 = (mpd_sint16 *)buffer1;
mpd_sint16 * buffer16_2 = (mpd_sint16 *)buffer2;
switch(format->bits) {
case 16:
while(bufferSize1>0 && bufferSize2>0) {
temp32 = *buffer16_1;
temp32+= *buffer16_2;
*buffer16_1 = temp32>32767 ? 32767 :
(temp32<-32768 ? -32768 : temp32);
buffer16_1++;
buffer16_2++;
bufferSize1-=2;
bufferSize2-=2;
}
if(bufferSize2>0) memcpy(buffer8_1,buffer8_2,bufferSize2);
break;
case 8:
while(bufferSize1>0 && bufferSize2>0) {
temp32 = *buffer8_1;
temp32+= *buffer8_2;
*buffer8_1 = temp32>127 ? 127 :
(temp32<-128 ? -128 : temp32);
buffer8_1++;
buffer8_2++;
bufferSize1--;
bufferSize2--;
}
if(bufferSize2>0) memcpy(buffer8_1,buffer8_2,bufferSize2);
break;
default:
ERROR("%i bits not supported by pcm_add!\n",format->bits);
exit(-1);
}
}
void pcm_mix(char * buffer1, char * buffer2, size_t bufferSize1,
size_t bufferSize2, AudioFormat * format, float portion1)
{
float s = sin(M_PI_2*portion1);
s*=s;
pcm_volumeChange(buffer1,bufferSize1,format,(int)(s*100));
pcm_volumeChange(buffer2,bufferSize2,format,(int)((1-s)*100));
pcm_add(buffer1,buffer2,bufferSize1,bufferSize2,format);
}
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