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/*
* Copyright (C) 2000 the xine project
*
* This file is part of xine, a unix video player.
* The code is heavily based on libmpeg from mpg123
*
* xine is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* xine is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*
* $Id: interface.c,v 1.6 2002/03/31 20:38:41 jcdutton Exp $
*/
#include <stdlib.h>
#include <stdio.h>
#include "mpg123.h"
#include "mpglib.h"
void mpg_audio_reset (mpgaudio_t *mp) {
mp->framesize = 0;
mp->framesize_old = -1;
mp->bsize = 0;
mp->fr.single = -1;
mp->bsnum = 0;
mp->synth_bo = 1;
mp->is_output_initialized = 0;
mp->sample_rate_device = 0;
mp->header = 0;
}
mpgaudio_t *mpg_audio_init (ao_instance_t *ao_output)
{
mpgaudio_t *mp;
mp = malloc (sizeof(struct mpstr));
memset(mp, 0, sizeof(struct mpstr));
make_decode_tables(32767);
init_layer2();
init_layer3(SBLIMIT);
mp->ao_output = ao_output;
mpg_audio_reset (mp);
return mp;
}
void mpg_audio_close (mpgaudio_t *mpg) {
free (mpg);
}
int head_check(struct mpstr *mp)
{
if( (mp->header & 0xffe00000) != 0xffe00000)
return 0;
if(!((mp->header>>17)&3))
return 0;
if( ((mp->header>>12)&0xf) == 0xf)
return 0;
if( ((mp->header>>10)&0x3) == 0x3 )
return 0;
return 1;
}
void mpg_audio_decode_data (mpgaudio_t *mp, uint8_t *data, uint8_t *data_end,
int64_t pts)
{
while (1) {
/* sync */
if(mp->framesize == 0) {
/* printf ("mpg123: looking for header\n"); */
while (!head_check (mp)) {
if (data == data_end)
return;
mp->header = (mp->header << 8) | *data;
data++;
}
/* decode header */
decode_header(&mp->fr,mp->header);
mp->framesize = mp->fr.framesize;
mp->bsize = 0;
mpg123_wordpointer = mp->bsspace[mp->bsnum] + 512;
mp->bsnum = (mp->bsnum + 1) & 0x1;
mpg123_bitindex = 0;
mp->pts = pts;
pts = 0;
}
/* copy data to bsspace */
while (mp->bsize<mp->framesize) {
if (data == data_end)
return;
*(mpg123_wordpointer + mp->bsize) = *data;
data++;
mp->bsize++;
}
if(mp->fr.error_protection)
getbits(16);
switch(mp->fr.lay) {
case 1:
do_layer1(mp);
break;
case 2:
do_layer2(mp);
break;
case 3:
do_layer3(mp);
break;
}
mp->framesize_old = mp->framesize;
mp->framesize = 0;
mp->header = 0;
}
}
int set_pointer(mpgaudio_t *mp, long backstep)
{
unsigned char *bsbufold;
if(mp->framesize_old < 0 && backstep > 0) {
fprintf(stderr,"Can't step back %ld!\n",backstep);
return 0;
}
bsbufold = mp->bsspace[mp->bsnum] + 512;
mpg123_wordpointer -= backstep;
if (backstep)
memcpy(mpg123_wordpointer,bsbufold+mp->framesize_old-backstep,backstep);
mpg123_bitindex = 0;
return 1;
}
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