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#include <stdio.h>
#include <stdlib.h>
#include "audio_out.h"
#include "audio_out_internal.h"
#include "afmt.h"
static ao_info_t info =
{
"mpeg-pes audio output",
"mpegpes",
"A'rpi",
""
};
LIBAO_EXTERN(mpegpes)
// to set/get/query special features/parameters
static int control(int cmd,int arg){
return -1;
}
// open & setup audio device
// return: 1=success 0=fail
static int init(int rate,int channels,int format,int flags){
ao_data.outburst=2000;
ao_data.format=format;
return 1;
}
// close audio device
static void uninit(){
}
// stop playing and empty buffers (for seeking/pause)
static void reset(){
}
// stop playing, keep buffers (for pause)
static void audio_pause()
{
// for now, just call reset();
reset();
}
// resume playing, after audio_pause()
static void audio_resume()
{
}
void send_pes_packet(unsigned char* data,int len,int id,int timestamp);
void send_lpcm_packet(unsigned char* data,int len,int id,int timestamp);
extern int vo_pts;
// return: how many bytes can be played without blocking
static int get_space(){
float x=(float)(vo_pts-ao_data.pts)/90000.0-0.5;
int y;
if(x<=0) return 0;
y=48000*4*x;y/=ao_data.outburst;y*=ao_data.outburst;
// printf("diff: %5.3f -> %d \n",x,y);
return y;
}
// plays 'len' bytes of 'data'
// it should round it down to outburst*n
// return: number of bytes played
static int play(void* data,int len,int flags){
if(ao_data.format==AFMT_MPEG)
send_pes_packet(data,len,0x1C0,ao_data.pts);
else {
int i;
unsigned short *s=data;
for(i=0;i<len/2;i++) s[i]=(s[i]>>8)|(s[i]<<8); // le<->be
send_lpcm_packet(data,len,0xA0,ao_data.pts);
}
return len;
}
// return: delay in seconds between first and last sample in buffer
static float get_delay(){
return 0.0;
}
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