feat: support for Matroska Video containers

[sss123next]

whole request is in request name.

[jef]

Not really following the request here. Are you suggesting that beets would be organizing Matroska container formats?

[sss123next]

yes, matroska is general purpose mediacontainer, which is efficient not only for video, but also for audio only streams, so it would be good to have support for it, it's much more simple to deal with one container for all audio encoders then supporting whole zoo of containers each with own benefits and limitations.

[jef]

This could potentially be out of scope of what beets does or depending on how you envision the metadata be manipulated. I'm unsure if any of the plugins would continue to work with a new format. I do understand that Matroska is a container and not an encoding, thus perhaps unravelling an MK* and manipulating the files within the contain could be possible. But I lack the knowledge of how metadata within Matroska Video containers work.

I would like some more input from other maintainers as this is pretty much out of my depth at this point.

[sss123next]

at this point my request is:
add support for matroska with audio streams as audiofiles, let's omit video completely for now.
lets assume what for example user have audio collection containing audio files, but in matroska container with mka extension.

one reason to do so: unified way to manage metadata (tags, covers, lyrics) with different audio encoders, which otherwise introducing some complications.

[jef]

So for example...

.
├── Fleetwood Mac - Rumors (1977).mka
│   ├── 01 - I Don't Want to Know.mp3
│   ├── 02 - Dreams.mp3
# --snip--

Beets would potentially open the mka container and run through its regular process on mp3s within the container?

[sss123next]

even simpler, treat file.mka same as file.mp3
look at real example:

mediainfo 01\ -\ Capricorn\ \(A\ Brand\ New\ Name\).opus.mka                                                                                                                   
General
Unique ID                                : 244225506267928789371084273768018984784 (0xB7BC1F1F3DC2A2C669A83CB877B3BF50)
Complete name                            : 01 - Capricorn (A Brand New Name).opus.mka
Format                                   : Matroska
Format version                           : Version 4
File size                                : 5.18 MiB
Duration                                 : 3 min 53 s
Overall bit rate                         : 186 kb/s
Writing application                      : Lavf58.51.100
Writing library                          : Lavf58.51.100
ErrorDetectionType                       : Per level 1

Video
ID                                       : 2
Format                                   : V_MJPEG
Codec ID                                 : V_MJPEG
Duration                                 : 7 ms
Width                                    : 500 pixels
Height                                   : 500 pixels
Display aspect ratio                     : 1.000
Frame rate mode                          : Constant
Color space                              : YUV
Default                                  : Yes
Forced                                   : No
Color range                              : Full
Matrix coefficients                      : BT.470 System B/G
Comment                                  : Cover (front)

Audio
ID                                       : 1
Format                                   : Opus
Codec ID                                 : A_OPUS
Duration                                 : 3 min 53 s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Bit depth                                : 16 bits
Compression mode                         : Lossy
Title                                    : Capricorn (A Brand New Name)
Writing library                          : Lavc58.100.100 libopus
Language                                 : English
Default                                  : Yes
Forced                                   : No
ALBUM                                    : 30 Seconds to Mars
ALBUMARTISTSORT                          : Thirty Seconds to Mars
ALBUM_ARTIST                             : Thirty Seconds to Mars
ARTIST                                   : Thirty Seconds to Mars
ARTISTS                                  : Thirty Seconds to Mars
ARTISTSORT                               : Thirty Seconds to Mars
ASIN                                     : B00006AFUR
BarCode                                  : 724381242407
CATALOGNUMBER                            : 7243 8 12424 0 7
COMPOSER                                 : Jared Leto
COMPOSERSORT                             : Leto, Jared
COVERART                                 : 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
COVERARTMIME                             : image/jpeg
Comment                                  : American; California (Songs-DB_Custom3);2000s (Songs-DB_Custom1);Nostalgia; Male Vocalists; Beautiful; Female Vocalists (Songs-DB_Custom2);Love (Songs-DB_Occasion)
DATE                                     : 2002-08-27
DISC                                     : 1
DISCTOTAL                                : 1
ENGINEER                                 : Brian Virtue
FORMAT                                   : CD
GENRE                                    : Alternative Rock
GROUPING                                 : Rock
ISRC                                     : USVI20200099
LABEL                                    : Immortal Records;Virgin
LEAD_PERFORMER                           : Jared Leto (synthesizer);Jared Leto (guitar);Jared Leto (bass);Shannon Leto (drums (drum set));Dr. Nner Tesy (additional synthesizer);Jared Leto (vocals)
LYRICIST                                 : Jared Leto
LYRICS                                   : So I run, hide and tear myself up / I'll start again with a brand new name / And eyes that see into infinity  / I will disappear / I told you once and I'll say it again / I want my message read clear / I'll show you the way, the way I'm going / So I run, hide and tear myself up / I'll start again with a brand new name / And eyes that see into infinity  / I was almost there / Just a moment away from becoming unclear / Ever get the feeling you're gone / I'll show you the way, the way I'm going / So I run, hide and tear myself up / I'll start again with a brand new name / And eyes that see into infinity /  / So I run, start again / With a brand new name / With a brand new name /  / So I run and hide and tell myself (so I run) / I'll start again with a brand new name (start again) / And eyes that see into infinity (with a brand new name) /  / I will disappear / 
MEDIA                                    : Enhanced CD
MIXER                                    : Ben Gross
MOOD                                     : Emotional; Sexy
MUSICBRAINZ_ALBUMARTISTID                : d8354b38-e942-4c89-ba93-29323432abc3
MUSICBRAINZ_ALBUMID                      : bfd86854-99cb-496e-b7c4-1c58c928ba1d
MUSICBRAINZ_ARTISTID                     : d8354b38-e942-4c89-ba93-29323432abc3
MUSICBRAINZ_RELEASEGROUPID               : 7a83ecca-b88e-3eab-b769-8d72dde013f7
MUSICBRAINZ_RELEASETRACKID               : 462492d7-2838-379e-9c3b-7f26851ca567
MUSICBRAINZ_TRACKID                      : 9cca163a-0a41-44dd-bf43-d51c2bf146c9
MUSICBRAINZ_WORKID                       : 413a37d8-8156-4152-9dfa-8ffb7b3f639d
MUSICIP_PUID                             : 88d38227-104c-198a-a6e7-f082afb206af
ORIGINALDATE                             : 2002-08-27
ORIGINALYEAR                             : 2002
PRODUCER                                 : Bob Ezrin;Thirty Seconds to Mars;Brian Virtue
R128_ALBUM_GAIN                          : -3789
R128_TRACK_GAIN                          : -3866
RELEASECOUNTRY                           : US
RELEASESTATUS                            : official
RELEASETYPE                              : album
REPLAYGAIN_ALBUM_GAIN                    : -10.04 dB
REPLAYGAIN_ALBUM_PEAK                    : 1.16074240
REPLAYGAIN_TRACK_GAIN                    : -9.12 dB
REPLAYGAIN_TRACK_PEAK                    : 1.11522508
SCRIPT                                   : Latn
TOTALDISCS                               : 1
TOTALTRACKS                              : 11
TRACKTOTAL                               : 11
Track/Position                           : 1
WEBSITE                                  : http://www.thirtysecondstomars.com/
WORK                                     : Capricorn (A Brand New Name)

but as i know handling container itself have some complications, for example musicbrainz picard still does not support mka because of problems with matroska in mutagen

[sss123next]

i guess best approach is just handle first found audiostream for start.

[pprkut]

beets is also reliant on support in mutagen, and once that's there, support needs to be added to mediafile

[sampsyo]

Indeed! I think the first step for any novel format requests is to look into what it would take to add support in Mutagen---or if there is already a feature request ticket there. For Matroska, there is: quodlibet/mutagen#3

Since there's no specific action for beets itself to take for now, let's close this issue. If you're interested in making this work, please consider contributing to the Mutagen feature.