[TIKA-1177] Add Matroska (mkv, mka) format detection

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.4
• Fix Version/s: 1.5
• Component/s: mime
• Assignee: Ray Gauss II
• Reporter: Boris Naguet
• Created: 02/Oct/13 15:47
• Updated: 25/Mar/14 16:21
• Resolved: 04/Oct/13 19:03

Description

There's no mimetype detection for Matroska format, although it's a popular video format.
Here is some code I added in my custom mimetypes to detect them:

	<mime-type type="video/x-matroska">
		<glob pattern="*.mkv" />
		<magic priority="40">
			<match value="0x1A45DFA3934282886d6174726f736b61" type="string" offset="0" />
		</magic>
	</mime-type>
	<mime-type type="audio/x-matroska">
		<glob pattern="*.mka" />
	</mime-type>

I found the signature for the mkv on:
http://www.garykessler.net/library/file_sigs.html
I was not able to find it clearly for mka, but detection by filename is still useful.

Although, the full spec is available here:
http://matroska.org/technical/specs/index.html
Maybe it's a bit more complex than this constant magic, but it works on my tests files.