AVC in MKV Container

[videophool]

I am looking for technical information about H264 in MKV container. Is there a specification or document that describes how it is stored?

[LoRd_MuldeR]

Matroska Basic Specs:
http://www.matroska.org/files/matroska.pdf

Matroska Codec Specs:
http://haali.su/mkv/codecs.pdf

[videophool]

Matroska Basic Specs:
http://www.matroska.org/files/matroska.pdf

Matroska Codec Specs:
http://haali.su/mkv/codecs.pdf
The haali spec is useful for the codec private data. Beyond that, I do not see any specific discussion of how the AVC data is carried. For example, are the SPS/PPS carried in the sample data? Also, using a hex editor to inspect the AVC data in the MKV, the AVC structure is not clear (I can'd identify the NAL units).

[Guest]

The NAL units are delimited not by 00 00 01 start codes but by a length field. I'll send you a code sample in an email. The SPS/PPS's are included in the data stream.

[LoRd_MuldeR]

About SPS/PPS the Haali document says:
SPSs and PPSs are concatenated and stored at dwSequenceHeader, without SPS and PPS counts

Also this post might be helpful about NALU's:
http://forum.doom9.org/showpost.php?p=1320024&postcount=11

EDIT: neuron2 was faster.

[Guest]

Thanks, Lord_Mulder, I forgot about that post.

Watch out for header compression too. For AVC a single 00 byte is stored as the "header" when header compression is enabled for the file. That shortens all the start codes, as it is to be prepended when extracting the data.