Maps a media type + format string to the canonical MIME type string. Handles special cases: jpg → image/jpeg, opus → audio/ogg.
jpg
image/jpeg
opus
audio/ogg
The media category: 'image', 'audio', or 'video'.
'image'
'audio'
'video'
The target format (e.g. 'webp', 'opus', 'mp4').
'webp'
'opus'
'mp4'
The MIME type string (e.g. 'image/webp', 'audio/ogg').
'image/webp'
'audio/ogg'
Maps a media type + format string to the canonical MIME type string. Handles special cases:
jpg→image/jpeg,opus→audio/ogg.