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better checks 

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@10370 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
arpi 2003-07-04 20:43:32 +00:00
parent 188460e7ee
commit a63bbf43fd
1 changed files with 25 additions and 24 deletions
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49
libmpdemux/mp3_hdr.c
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@ -14,7 +14,10 @@ static int tabsel_123[2][3][16] = {
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,0},
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,0} }
};
static long freqs[9] = { 44100, 48000, 32000, 22050, 24000, 16000 , 11025 , 12000 , 8000 };
static long freqs[9] = { 44100, 48000, 32000, // MPEG 1.0
22050, 24000, 16000, // MPEG 2.0
11025, 12000 , 8000 }; // MPEG 2.5
int mp_mp3_get_lsf(unsigned char* hbuf){
unsigned long newhead =
@ -32,7 +35,7 @@ int mp_mp3_get_lsf(unsigned char* hbuf){
* return frame size or -1 (bad frame)
*/
int mp_get_mp3_header(unsigned char* hbuf,int* chans, int* srate){
int stereo,ssize,crc,lsf,mpeg25,framesize,padding,bitrate_index,sampling_frequency;
int stereo,ssize,lsf,framesize,padding,bitrate_index,sampling_frequency;
unsigned long newhead =
hbuf[0] << 24 |
hbuf[1] << 16 |
@ -43,8 +46,7 @@ int mp_get_mp3_header(unsigned char* hbuf,int* chans, int* srate){
#if 1
// head_check:
if( (newhead & 0xffe00000) != 0xffe00000 ||
(newhead & 0x0000fc00) == 0x0000fc00){
if( (newhead & 0xffe00000) != 0xffe00000 ){
mp_msg(MSGT_DEMUXER,MSGL_DBG2,"head_check failed\n");
return -1;
}
@ -55,25 +57,23 @@ int mp_get_mp3_header(unsigned char* hbuf,int* chans, int* srate){
return -1;
}
if( newhead & ((long)1<<20) ) {
lsf = (newhead & ((long)1<<19)) ? 0x0 : 0x1;
mpeg25 = 0;
} else {
lsf = 1;
mpeg25 = 1;
}
if(mpeg25)
sampling_frequency = 6 + ((newhead>>10)&0x3);
else
sampling_frequency = ((newhead>>10)&0x3) + (lsf*3);
if(sampling_frequency>8){
sampling_frequency = ((newhead>>10)&0x3);
if(sampling_frequency==3){
mp_msg(MSGT_DEMUXER,MSGL_DBG2,"invalid sampling_frequency\n");
return -1; // valid: 0..8
}
crc = ((newhead>>16)&0x1)^0x1;
if( newhead & ((long)1<<20) ) {
// MPEG 1.0 (lsf==0) or MPEG 2.0 (lsf==1)
lsf = (newhead & ((long)1<<19)) ? 0x0 : 0x1;
sampling_frequency += (lsf*3);
} else {
// MPEG 2.5
lsf = 1;
sampling_frequency += 6;
}
// crc = ((newhead>>16)&0x1)^0x1;
bitrate_index = ((newhead>>12)&0xf);
padding = ((newhead>>9)&0x1);
// fr->extension = ((newhead>>8)&0x1);
@ -85,16 +85,17 @@ int mp_get_mp3_header(unsigned char* hbuf,int* chans, int* srate){
stereo = ( (((newhead>>6)&0x3)) == 3) ? 1 : 2;
if(!bitrate_index){
mp_msg(MSGT_DEMUXER,MSGL_DBG2,"Free format not supported.\n");
return -1;
}
// !checked later through tabsel_123[]!
// if(!bitrate_index || bitrate_index==15){
// mp_msg(MSGT_DEMUXER,MSGL_DBG2,"Free format not supported.\n");
// return -1;
// }
if(lsf)
ssize = (stereo == 1) ? 9 : 17;
else
ssize = (stereo == 1) ? 17 : 32;
if(crc) ssize += 2;
if(!((newhead>>16)&0x1)) ssize += 2; // CRC
framesize = tabsel_123[lsf][2][bitrate_index] * 144000;