[foms] Chunks

[Steve Lhomme]

> If you look at this document: http://www.matroska.org/technical/order/index.html
> You only need Segment Info, Track Info, Clusters. These are all
> contained in a Segment, which can have an undefined/infinite size. So
> the server doesn't have to cache data in memory to know the exact size
> before "closing" the Segment. Same thing for all the Clusters,
> although they should typically match those of the original WebM file.
> Plus Clusters are usually around 2s and for WebM the video should
> start with a keyframe, so no extra logic needs to be applied here.
> This kind of simplistic files/chunks will work fine in any known
> player Matroska players.

PS: These files are also totally valid according to the Matroska and
WebM specs. mkvalidator will issue a warning if you have more than one
Cluster and no Cues. But then seeking in such files is not meant to
happen direclty using the Matroska data but rather what the manifest
says.