[FFmpeg-cvslog] movdec: Parse the dvc1 atom

Martin Storsjö git at videolan.org
Fri Feb 3 04:16:00 CET 2012


ffmpeg | branch: master | Martin Storsjö <martin at martin.st> | Sun Jan 22 01:32:16 2012 +0200| [89415b8e3fb83d67fdc518323cc364aa74ec2af2] | committer: Martin Storsjö

movdec: Parse the dvc1 atom

Normally, the actual payload data contains sequence headers, too,
and the parser can extract this and set it as extradata. However,
the data in the dvc1 atom is the "official" extradata for the file.

This is required for proper stream copy of vc1 from ismv to ismv.

Signed-off-by: Martin Storsjö <martin at martin.st>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=89415b8e3fb83d67fdc518323cc364aa74ec2af2
---

 libavformat/mov.c |   27 +++++++++++++++++++++++++++
 1 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 3c1927f..d0e01f8 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -971,6 +971,32 @@ static int mov_read_glbl(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     return 0;
 }
 
+static int mov_read_dvc1(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+    AVStream *st;
+    uint8_t profile_level;
+
+    if (c->fc->nb_streams < 1)
+        return 0;
+    st = c->fc->streams[c->fc->nb_streams-1];
+
+    if (atom.size >= (1<<28) || atom.size < 7)
+        return AVERROR_INVALIDDATA;
+
+    profile_level = avio_r8(pb);
+    if (profile_level & 0xf0 != 0xc0)
+        return 0;
+
+    av_free(st->codec->extradata);
+    st->codec->extradata = av_mallocz(atom.size - 7 + FF_INPUT_BUFFER_PADDING_SIZE);
+    if (!st->codec->extradata)
+        return AVERROR(ENOMEM);
+    st->codec->extradata_size = atom.size - 7;
+    avio_seek(pb, 6, SEEK_CUR);
+    avio_read(pb, st->codec->extradata, st->codec->extradata_size);
+    return 0;
+}
+
 /**
  * An strf atom is a BITMAPINFOHEADER struct. This struct is 40 bytes itself,
  * but can have extradata appended at the end after the 40 bytes belonging
@@ -2435,6 +2461,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
 { MKTAG('w','f','e','x'), mov_read_wfex },
 { MKTAG('c','m','o','v'), mov_read_cmov },
 { MKTAG('c','h','a','n'), mov_read_chan }, /* channel layout */
+{ MKTAG('d','v','c','1'), mov_read_dvc1 },
 { 0, NULL }
 };
 



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