mpv/libmpcodecs/ad_dvdpcm.c

146 lines
3.3 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"
#include "ad_internal.h"
static ad_info_t info =
{
"Uncompressed DVD/VOB LPCM audio decoder",
"dvdpcm",
"Nick Kurshev",
"A'rpi",
""
};
LIBAD_EXTERN(dvdpcm)
static int init(sh_audio_t *sh)
{
/* DVD PCM Audio:*/
sh->i_bps = 0;
if(sh->codecdata_len==3){
// we have LPCM header:
unsigned char h=sh->codecdata[1];
sh->channels=1+(h&7);
switch((h>>4)&3){
case 0: sh->samplerate=48000;break;
case 1: sh->samplerate=96000;break;
case 2: sh->samplerate=44100;break;
case 3: sh->samplerate=32000;break;
}
switch ((h >> 6) & 3) {
case 0:
sh->sample_format = AF_FORMAT_S16_BE;
sh->samplesize = 2;
break;
case 1:
mp_msg(MSGT_DECAUDIO, MSGL_INFO, MSGTR_SamplesWanted);
sh->i_bps = sh->channels * sh->samplerate * 5 / 2;
case 2:
sh->sample_format = AF_FORMAT_S24_BE;
sh->samplesize = 3;
break;
default:
sh->sample_format = AF_FORMAT_S16_BE;
sh->samplesize = 2;
}
} else {
// use defaults:
sh->channels=2;
sh->samplerate=48000;
sh->sample_format = AF_FORMAT_S16_BE;
sh->samplesize = 2;
}
if (!sh->i_bps)
sh->i_bps = sh->samplesize * sh->channels * sh->samplerate;
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 j,len;
if (sh_audio->samplesize == 3) {
if (((sh_audio->codecdata[1] >> 6) & 3) == 1) {
// 20 bit
// not sure if the "& 0xf0" and "<< 4" are the right way around
// can somebody clarify?
for (j = 0; j < minlen; j += 12) {
char tmp[10];
len = demux_read_data(sh_audio->ds, tmp, 10);
if (len < 10) break;
// first sample
buf[j + 0] = tmp[0];
buf[j + 1] = tmp[1];
buf[j + 2] = tmp[8] & 0xf0;
// second sample
buf[j + 3] = tmp[2];
buf[j + 4] = tmp[3];
buf[j + 5] = tmp[8] << 4;
// third sample
buf[j + 6] = tmp[4];
buf[j + 7] = tmp[5];
buf[j + 8] = tmp[9] & 0xf0;
// fourth sample
buf[j + 9] = tmp[6];
buf[j + 10] = tmp[7];
buf[j + 11] = tmp[9] << 4;
}
len = j;
} else {
// 24 bit
for (j = 0; j < minlen; j += 12) {
char tmp[12];
len = demux_read_data(sh_audio->ds, tmp, 12);
if (len < 12) break;
// first sample
buf[j + 0] = tmp[0];
buf[j + 1] = tmp[1];
buf[j + 2] = tmp[8];
// second sample
buf[j + 3] = tmp[2];
buf[j + 4] = tmp[3];
buf[j + 5] = tmp[9];
// third sample
buf[j + 6] = tmp[4];
buf[j + 7] = tmp[5];
buf[j + 8] = tmp[10];
// fourth sample
buf[j + 9] = tmp[6];
buf[j + 10] = tmp[7];
buf[j + 11] = tmp[11];
}
len = j;
}
} else
len=demux_read_data(sh_audio->ds,buf,(minlen+3)&(~3));
return len;
}