Commit 7da1f00e authored by Michael Niedermayer's avatar Michael Niedermayer

Merge commit 'c1d647b1'

* commit 'c1d647b1':
  mp3: Make the seek more robust

Conflicts:
	libavformat/mp3dec.c

Mostly not merged

See: b6267901 and various later commits

The bug is also not reproducable in FFmpeg
Merged-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parents ba77fb61 c1d647b1
......@@ -54,7 +54,7 @@ typedef struct {
int is_cbr;
} MP3DecContext;
static int check(AVFormatContext *s, int64_t pos);
static int check(AVIOContext *pb, int64_t pos);
/* mp3 read */
......@@ -376,7 +376,7 @@ static int mp3_read_header(AVFormatContext *s)
for (i = 0; i < 64 * 1024; i++) {
if (!(i&1023))
ffio_ensure_seekback(s->pb, i + 1024 + 4);
if (check(s, off + i) >= 0) {
if (check(s->pb, off + i) >= 0) {
av_log(s, AV_LOG_INFO, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
avio_seek(s->pb, off + i, SEEK_SET);
break;
......@@ -418,18 +418,22 @@ static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
return ret;
}
static int check(AVFormatContext *s, int64_t pos)
#define SEEK_WINDOW 4096
static int check(AVIOContext *pb, int64_t pos)
{
int64_t ret = avio_seek(s->pb, pos, SEEK_SET);
int64_t ret = avio_seek(pb, pos, SEEK_SET);
unsigned header;
MPADecodeHeader sd;
if (ret < 0)
return ret;
header = avio_rb32(s->pb);
header = avio_rb32(pb);
if (ff_mpa_check_header(header) < 0)
return -1;
if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
return -1;
return sd.frame_size;
}
......@@ -466,7 +470,7 @@ static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
return -1;
}
avio_seek(s->pb, FFMAX(ie->pos - 4096, 0), SEEK_SET);
avio_seek(s->pb, FFMAX(ie->pos - SEEK_WINDOW, 0), SEEK_SET);
ret = avio_seek(s->pb, ie->pos, SEEK_SET);
if (ret < 0)
return ret;
......@@ -474,8 +478,8 @@ static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
#define MIN_VALID 3
best_pos = ie->pos;
best_score = 999;
for(i=0; i<4096; i++) {
int64_t pos = ie->pos + (dir > 0 ? i - 1024 : -i);
for(i=0; i<SEEK_WINDOW; i++) {
int64_t pos = ie->pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
int64_t candidate = -1;
int score = 999;
......@@ -483,7 +487,7 @@ static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
continue;
for(j=0; j<MIN_VALID; j++) {
ret = check(s, pos);
ret = check(s->pb, pos);
if(ret < 0)
break;
if ((ie->pos - pos)*dir <= 0 && abs(MIN_VALID/2-j) < score) {
......
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