matroska

What a Matroska file says about its segment, its editions and their chapters, which a player needs to play ordered chapters and linked segments. Null for a source that is not Matroska, and for a Matroska file read through an FFmpeg that does not hand these facts out, so null means unknown rather than "no editions". Read when the source opens. See MatroskaSegment.

What a Matroska file says about its segment, its editions and their chapters, which a player needs to play ordered chapters and linked segments. Null for a source that is not Matroska, and for a Matroska file read through an FFmpeg that does not hand these facts out, so null means unknown rather than "no editions". Read when the source opens. See MatroskaSegment.

What a Matroska file says about its segment, its editions and their chapters, which a player needs to play ordered chapters and linked segments. Null for a source that is not Matroska, and for a Matroska file read through an FFmpeg that does not hand these facts out, so null means unknown rather than "no editions". Read when the source opens. See MatroskaSegment.

What a Matroska file says about its segment, its editions and their chapters, which a player needs to play ordered chapters and linked segments. Null for a source that is not Matroska, and for a Matroska file read through an FFmpeg that does not hand these facts out, so null means unknown rather than "no editions". Read when the source opens. See MatroskaSegment.

Read once, at the first ask, because the payloads it comes from never change after the open.