RepoMirrors
/
mpv
mirror of https://github.com/mpv-player/mpv
1
0
Fork 0
Code Issues Releases Wiki Activity

demux_audio: do not decode ID3v2 tag data as audio data 

Minor simplification.

Part of patch by Benoît Thébaudeau [benoit thebaudeau () advansee com].

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@34718 b3059339-0415-0410-9bf9-f77b7e298cf2

Detect ID3v2 tag at the end of the file and stop demuxing before
its start.
Avoids trying to decode its data as MP3.
Patch by Benoît Thébaudeau [benoit thebaudeau {} advansee com].

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@34719 b3059339-0415-0410-9bf9-f77b7e298cf2

Author: reimar
This commit is contained in:
mplayer-svn 2012-02-13 19:33:48 +00:00 committed by wm4
parent b615b66322
commit 3fa539c4e2
1 changed files with 53 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
libmpdemux/demux_audio.c
View File

@ -320,6 +320,34 @@ static unsigned int mp3_vbr_frames(stream_t *s, off_t off) {
return 0;
}
/**
* @brief Determine the total size of an ID3v2 tag.
*
* @param maj_ver major version of the ID3v2 tag
* @param s stream to be read, assumed to be positioned at revision byte
*
* @return 0 (error or malformed tag) or tag size
*/
static unsigned int id3v2_tag_size(uint8_t maj_ver, stream_t *s) {
unsigned int header_footer_size;
unsigned int size;
int i;
if(stream_read_char(s) == 0xff)
return 0;
header_footer_size = ((stream_read_char(s) & 0x10) && maj_ver >= 4) ? 20 : 10;
size = 0;
for(i = 0; i < 4; i++) {
uint8_t data = stream_read_char(s);
if (data & 0x80)
return 0;
size = size << 7 | data;
}
return header_footer_size + size;
}
static int demux_audio_open(demuxer_t* demuxer) {
stream_t *s;
sh_audio_t* sh_audio;
@ -353,12 +381,10 @@ static int demux_audio_open(demuxer_t* demuxer) {
// We found wav header. Now we can have 'fmt ' or a mp3 header
// empty the buffer
step = 4;
} else if( hdr[0] == 'I' && hdr[1] == 'D' && hdr[2] == '3' && (hdr[3] >= 2)) {
int len;
stream_skip(s,2);
stream_read(s,hdr,4);
len = (hdr[0]<<21) | (hdr[1]<<14) | (hdr[2]<<7) | hdr[3];
stream_skip(s,len);
} else if( hdr[0] == 'I' && hdr[1] == 'D' && hdr[2] == '3' && hdr[3] >= 2 && hdr[3] != 0xff) {
unsigned int len = id3v2_tag_size(hdr[3], s);
if(len > 0)
stream_skip(s,len-10);
step = 4;
} else if( found_WAVE && hdr[0] == 'f' && hdr[1] == 'm' && hdr[2] == 't' && hdr[3] == ' ' ) {
frmt = WAV;
@ -412,11 +438,9 @@ static int demux_audio_open(demuxer_t* demuxer) {
free(mp3_found);
mp3_found = NULL;
if(s->end_pos && (s->flags & MP_STREAM_SEEK) == MP_STREAM_SEEK) {
char tag[4];
stream_seek(s,s->end_pos-128);
stream_read(s,tag,3);
tag[3] = '\0';
if(!strcmp(tag,"TAG")) {
stream_read(s,hdr,3);
if(!memcmp(hdr,"TAG",3)) {
char buf[31];
uint8_t g;
demuxer->movi_end = stream_tell(s)-3;
@ -443,6 +467,25 @@ static int demux_audio_open(demuxer_t* demuxer) {
g = stream_read_char(s);
demux_info_add(demuxer,"Genre",genres[g]);
}
stream_seek(s,demuxer->movi_end-10);
stream_read(s,hdr,4);
if(!memcmp(hdr,"3DI",3) && hdr[3] >= 4 && hdr[3] != 0xff) {
unsigned int len = id3v2_tag_size(hdr[3], s);
if(len > 0) {
if(len > demuxer->movi_end - demuxer->movi_start) {
mp_msg(MSGT_DEMUX,MSGL_WARN,"Audio demuxer: bad ID3v2 tag size: larger than stream (%u).\n",len);
len = FFMIN(10,demuxer->movi_end-demuxer->movi_start);
} else {
stream_seek(s,demuxer->movi_end-len);
stream_read(s,hdr,4);
if(memcmp(hdr,"ID3",3) || hdr[3] < 4 || hdr[3] == 0xff || id3v2_tag_size(hdr[3], s) != len) {
mp_msg(MSGT_DEMUX,MSGL_WARN,"Audio demuxer: damaged appended ID3v2 tag detected.\n");
len = FFMIN(10,demuxer->movi_end-demuxer->movi_start);
}
}
demuxer->movi_end -= len;
}
}
}
if (duration && demuxer->movi_end && demuxer->movi_end > demuxer->movi_start) sh_audio->wf->nAvgBytesPerSec = (demuxer->movi_end - demuxer->movi_start) / duration;
sh_audio->i_bps = sh_audio->wf->nAvgBytesPerSec;