From 9a099526954962893f95d90ce202d07ea90d300c Mon Sep 17 00:00:00 2001
From: Thierry Foucu <tfoucu@gmail.com>
Date: Fri, 29 Jan 2016 10:47:49 -0800
Subject: [PATCH] lavf/flvdec: Allow files where the PreviousTagSize is not set
according to the spec.
Some muxer use the FLV field PreviousTagSize to be the sum of tag
length. Without this change, the flv demuxer think the file is broken
and the re-sync will fail.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavformat/flvdec.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/libavformat/flvdec.c b/libavformat/flvdec.c
index e72bc81d904..5090ac21579 100644
--- a/libavformat/flvdec.c
+++ b/libavformat/flvdec.c
@@ -60,6 +60,7 @@ typedef struct FLVContext {
uint8_t resync_buffer[2*RESYNC_BUFFER_SIZE];
int broken_sizes;
+ int sum_flv_tag_size;
} FLVContext;
static int probe(AVProbeData *p, int live)
@@ -629,6 +630,7 @@ static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)
static int flv_read_header(AVFormatContext *s)
{
int offset, flags;
+ FLVContext *flv = s->priv_data;
avio_skip(s->pb, 4);
flags = avio_r8(s->pb);
@@ -649,6 +651,7 @@ static int flv_read_header(AVFormatContext *s)
avio_skip(s->pb, 4);
s->start_time = 0;
+ flv->sum_flv_tag_size = 0;
return 0;
}
@@ -857,6 +860,7 @@ retry:
type = (avio_r8(s->pb) & 0x1F);
orig_size =
size = avio_rb24(s->pb);
+ flv->sum_flv_tag_size += size + 11;
dts = avio_rb24(s->pb);
dts |= (unsigned)avio_r8(s->pb) << 24;
av_log(s, AV_LOG_TRACE, "type:%d, size:%d, last:%d, dts:%"PRId64" pos:%"PRId64"\n", type, size, last, dts, avio_tell(s->pb));
@@ -1141,7 +1145,7 @@ retry_duration:
leave:
last = avio_rb32(s->pb);
if (last != orig_size + 11 &&
- (last != orig_size || !last) &&
+ (last != orig_size || !last) && last != flv->sum_flv_tag_size &&
!flv->broken_sizes) {
av_log(s, AV_LOG_ERROR, "Packet mismatch %d %d\n", last, orig_size + 11);
avio_seek(s->pb, pos + 1, SEEK_SET);
--
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