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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "ad_internal.h"
static ad_info_t info =
{
"Uncompressed PCM audio decoder",
"pcm",
"Nick Kurshev",
"A'rpi",
""
};
LIBAD_EXTERN(pcm)
static int init(sh_audio_t *sh_audio)
{
WAVEFORMATEX *h=sh_audio->wf;
sh_audio->i_bps=h->nAvgBytesPerSec;
sh_audio->channels=h->nChannels;
sh_audio->samplerate=h->nSamplesPerSec;
sh_audio->samplesize=(h->wBitsPerSample+7)/8;
switch(sh_audio->format){ /* hardware formats: */
case 0x6: sh_audio->sample_format=AFMT_A_LAW;break;
case 0x7: sh_audio->sample_format=AFMT_MU_LAW;break;
case 0x11: sh_audio->sample_format=AFMT_IMA_ADPCM;break;
case 0x50: sh_audio->sample_format=AFMT_MPEG;break;
/* case 0x2000: sh_audio->sample_format=AFMT_AC3; */
case 0x736F7774: // 'twos'
case 0x74776F73: // 'swot'
if(sh_audio->samplesize==1) sh_audio->sample_format=AFMT_S8;
sh_audio->ds->ss_div= sh_audio->samplesize;
sh_audio->ds->ss_mul= sh_audio->samplesize * sh_audio->channels;
break;
default: if(sh_audio->samplesize!=2) sh_audio->sample_format=AFMT_U8;
}
return 1;
}
static int preinit(sh_audio_t *sh)
{
sh->audio_out_minsize=2048;
return 1;
}
static void uninit(sh_audio_t *sh)
{
}
static int control(sh_audio_t *sh,int cmd,void* arg, ...)
{
int skip;
switch(cmd)
{
case ADCTRL_SKIP_FRAME:
skip=sh->i_bps/16;
skip=skip&(~3);
demux_read_data(sh->ds,NULL,skip);
return CONTROL_TRUE;
}
return CONTROL_UNKNOWN;
}
static int decode_audio(sh_audio_t *sh_audio,unsigned char *buf,int minlen,int maxlen)
{
int len=sh_audio->channels*sh_audio->samplesize-1;
len=(minlen+len)&(~len); // sample align
len=demux_read_data(sh_audio->ds,buf,len);
#ifdef WORDS_BIGENDIAN
if(sh_audio->format!=0x736F7774){
#else
if(sh_audio->format==0x736F7774){ // "twos" is swapped byteorder
#endif
int j;
for(j=0;j<len;j+=2){
char x=buf[j];
buf[j]=buf[j+1];
buf[j+1]=x;
}
}
return len;
}
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