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https://issues.apache.org/jira/browse/TIKA-2935?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16931467#comment-16931467
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Nick Burch commented on TIKA-2935:
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The MP4 format is a container format, and those really do need a dedicated
container-aware detector to do detection correctly. Tika provides ones (in the
parsers package) for formats like ZIP and OLE2. For media formats, we have an
Ogg one (for complex historical reasons in a third party repo that's pulled in)
We don't currently have anything like that for MP4. Instead, all we have is a
check of the type of the first atom, via mime magic. If that's a well known
one, we return the specific type, otherwise the general one
If this is something you'd like to work on, great! Please take a look at
[https://github.com/Gagravarr/VorbisJava/blob/master/tika/src/main/java/org/gagravarr/tika/OggDetector.java]
for an example of how to do media container-based detection.
Tika has a bit of mp4 detection logic in the parser class, see MP4Parser.
Probably you'd need to refactor that out to a new Detector, to be re-used by
the parser, then add additional logic to check the streams for cases where the
FileTypeBox atom is missing on inconclusive
> MP4 content type identified as application/mp4 rather than video/mp4
> --------------------------------------------------------------------
>
> Key: TIKA-2935
> URL: https://issues.apache.org/jira/browse/TIKA-2935
> Project: Tika
> Issue Type: Bug
> Components: detector, mime
> Affects Versions: 1.21
> Reporter: Steven Baskin
> Priority: Minor
> Attachments: Smile_Doctors_-_Team_Members.mp4
>
>
> Im currently trying to use Tika detector to identify the content type of the
> file attached to this ticket. Using both the default detector with default
> config in java and the {{tika-app-1.21 }}jar the type is being returned as
> {{application/mp4}}.
> According to [https://tools.ietf.org/html/rfc4337]::
> {quote}Selection of MIME Types for MP4 Files
> The MIME types to be assigned to MP4 files are selected according to
> the contents. Basic guidelines for selecting MIME types are as
> follows:
> a) if the file contains neither visual nor audio presentations, but
> only, for example, MPEG-J or MPEG-7, use application/mp4;
> b) for all other files, including those that have MPEG-J, etc., in
> addition to video or audio streams, video/mp4 should be used;
> however:
> c) for files with audio but no visual aspect, including those that
> have MPEG-J, etc., in addition to audio streams, audio/mp4 may be
> used.
> {quote}
> As the file has both video and audio components, it seems this file type
> should be identified as {{video/mp4.}}
> I was hoping to get some help in working out whether this a bug that can be
> fixed or if there is a problem on my end.
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