breeze/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2026-02-04 14:30:55 +08:00
Code Issues Packages Projects Releases Wiki Activity

avformat/dhav: handle files missing data at start

Browse Source 
Try to seek to end of file and if signature is found seek backwards until
last valid chunk is found.
This commit is contained in:
Paul B Mahol
2019-08-24 18:03:46 +02:00
committed by Kieran Kunhya
parent 96fd07351a
commit 45cefca1e7
1 changed files with 19 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
libavformat/dhav.c
View File

@@ -73,15 +73,30 @@ static int dhav_read_header(AVFormatContext *s)
ffio_ensure_seekback(s->pb, 5);
avio_read(s->pb, signature, sizeof(signature));
if (!memcmp(signature, "DAHUA", 5))
if (!memcmp(signature, "DAHUA", 5)) {
avio_skip(s->pb, 0x400 - 5);
else
avio_seek(s->pb, -5, SEEK_CUR);
dhav->last_good_pos = avio_tell(s->pb);
} else {
if (!memcmp(signature, "DHAV", 4)) {
avio_seek(s->pb, -5, SEEK_CUR);
dhav->last_good_pos = avio_tell(s->pb);
} else if (s->pb->seekable) {
avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
while (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
int seek_back;
seek_back = avio_rl32(s->pb) + 8;
dhav->last_good_pos = avio_tell(s->pb);
if (dhav->last_good_pos < seek_back)
break;
avio_seek(s->pb, -seek_back, SEEK_CUR);
}
}
}
s->ctx_flags |= AVFMTCTX_NOHEADER;
dhav->video_stream_index = -1;
dhav->audio_stream_index = -1;
dhav->last_good_pos = avio_tell(s->pb);
return 0;
}