column "Type" in directory listing assumes multimedia containers must store video

[auroraanna]

Distribution

NixOS (nixpkgs commit rev 57610d2f8f0937f39dbd72251e9614b1561942d8), Linux 6.12.11

Package version

6.4.4

Frequency

Always

Bug description

Nemo lists all Matroska and MP4 files (and probably a bunch of other multimedia containers) as being of the Type Video despite them not requiring there to be a video stream in the container. multimedia containers can contain only still images, only audio, only video or a combination of the previous. Therefore it is wrong to label them as Type Video. Infact, Matroska even has the mimetypes video/x-matroska and audio/x-matroska.
I could store an entire library of lossless music, mind you, with cover art and metadata like artist, release date in Matroska containers.

Steps to reproduce

Create a Mastroska file without a video stream:

1. use ffmpeg to create a Matroska file without video out of any container that has at least one audio stream (e.g. a FLAC, an MP4, an MP3, …) and discard all video: ffmpeg -i $input_container -vn -acodec copy no_video.mkv
2. nemo .
3. type "no video" to select the file and view it's Type

Expected behavior

This, I'm not sure about. For correctly displaying a type for multimedia containers, nemo would have to scan every one of these files for what kind of streams and attachments they contain. But without doing this, it is just assuming, which can be wrong. I think Type should be a combination of

• "Video"
• "Audio"
• "Image"
• possibly "Subtitles"

with " + " in between these strings if several are present. Otherwise, i think it would be sort of reasonable to display "Video", when the container contains video, regardless of it contains audio e.g. and to display "Audio", when the container does not container video but might still contain an image e.g.

Additional information

No response

[mtwebster]

There's a 'Detailed type' column you can add instead (right-click one of the column headers to enable it) - this may be more accurate.

[auroraanna]

for Matroska it says "Matroska video" for Matroska files with no video, oh well
if it said "Matroska container" or just "Matroska" i would rather use the Detailed Type, but this does not fix the issue that the Type is lying to users about the contents of files.