/*
* play a frame read by read_frame();
* (re)initialize audio if necessary.
*/
static void decode_frame(APEG_LAYER *layer, struct frame *fr, struct mpstr *mp)
{
int clip;
/* do the decoding */
switch(fr->lay)
{
case 1:
clip = do_layer1(mp, fr, layer);
break;
case 2:
clip = do_layer2(mp, fr, layer);
break;
case 3:
clip = do_layer3(mp, fr, layer);
break;
default:
// Shouldn't get here...
clip = 1;
mp->return_later = FALSE;
}
if(clip < 0)
apeg_error_jump("Error decoding audio frame");
}
int MPGLIB_DecodeFrame(PMPSTR mp, const unsigned char* in, void* out)
{
int done;
/* First decode header */
mp->header =
(((unsigned long)in[0]) << 24) |
(((unsigned long)in[1]) << 16) |
(((unsigned long)in[2]) << 8) |
(((unsigned long)in[3]));
decode_header(&mp->fr, mp->header);
mp->framesize = mp->fr.framesize;
mp->wordpointer = mp->bsspace[mp->bsnum] + 512;
mp->bsnum = (mp->bsnum + 1) & 0x1;
mp->bitindex = 0;
memcpy(mp->wordpointer, in+4, mp->framesize);
done = 0;
if(mp->fr.error_protection)
getbits(mp, 16);
switch(mp->fr.lay) {
case 1:
do_layer1(mp,(unsigned char *) out, &done);
break;
case 2:
do_layer2(mp,(unsigned char *) out, &done);
break;
case 3:
do_layer3(mp,(unsigned char *) out, &done, synth_1to1_mono, synth_1to1);
break;
}
mp->fsizeold = mp->framesize;
mp->framesize = 0;
if (done) {
return MP3_OK;
} else {
return MP3_INVALID_BITS;
}
}
int decodeMP3(struct mpstr *mp,char *in,int isize,char *out,
int osize,int *done)
{
int len;
gmp = mp;
if(osize < 4608) {
// fprintf(stderr,"To less out space\n");
return MP3_ERR;
}
if(in) {
if(addbuf(mp,in,isize) == NULL) {
return MP3_ERR;
}
}
/* First decode header */
if(mp->framesize == 0) {
if(mp->bsize < 4) {
return MP3_NEED_MORE;
}
read_head(mp);
decode_header(&mp->fr,mp->header);
mp->framesize = mp->fr.framesize;
}
if(mp->fr.framesize > mp->bsize)
return MP3_NEED_MORE;
wordpointer = mp->bsspace[mp->bsnum] + 512;
mp->bsnum = (mp->bsnum + 1) & 0x1;
bitindex = 0;
len = 0;
while(len < mp->framesize) {
int nlen;
int blen = mp->tail->size - mp->tail->pos;
if( (mp->framesize - len) <= blen) {
nlen = mp->framesize-len;
}
else {
nlen = blen;
}
memcpy(wordpointer+len,mp->tail->pnt+mp->tail->pos,nlen);
len += nlen;
mp->tail->pos += nlen;
mp->bsize -= nlen;
if(mp->tail->pos == mp->tail->size) {
remove_buf(mp);
}
}
*done = 0;
if(mp->fr.error_protection)
getbits(16);
switch(mp->fr.lay) {
case 1:
do_layer1(&mp->fr,(unsigned char *) out,done);
break;
case 2:
do_layer2(&mp->fr,(unsigned char *) out,done);
break;
case 3:
do_layer3(&mp->fr,(unsigned char *) out,done);
break;
}
mp->fsizeold = mp->framesize;
mp->framesize = 0;
return MP3_OK;
}
