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Using wav files have very limited standard support for tagging - how do people tag these files?
BTW, this is really an interesting topic, I even thought to ask you whether you plan to implement wav chunks support.
I remember some years ago (I was doing some track mastering of my friend's band) I was looking desperately for an audio organizer that support wav chunks reading/tagging. If I remember well, the only such tool at that time was MAC (MPEG Audio Collection), now discontinued.
Anyway, it seems that there is a consensus about the basic chunks, below you can find the ones used by GoldWave and Sondforge:
GoldWave
-------------
IART Artist
ICMT Description
ICOP Copyright
ICRD Date YYYY/MM/DD HH:MM:SS
IGNR Genre
INAM Title
IPRD Album
iaar Album Artist
isrc ISRC
itrk Tracknumber
iurl URL
SoundForge
----------------
IARL Archival location
IART Artist
ICMS Commissioned
ICMT Comments
ICOP Copyright
ICRD Creation Date
ICRP Croppped
IDIM Dimmensions
IDPI Dots Per Inch
IENG Engineer
IGNR Genre
IKEY Keywords
ILGT Lightness
IMED Medium
INAM Name/Title
IPLT Palette Settings
IPRD Product
ISBJ Subject
ISFT Software/Encoded By
ISHP Sharpness
ISRC Source
ISRF Source Form
ITCH Technician
DISP Sound Scheme Title (picture)
Actually, SF use DISP chunk to store images (album art), I don't know what format is used.
Also some other chunks may be seen here and there, such as:
IDIM Dimensions
IDPI DPI
IKEY Keywords
ITRK Track
TRCK Track
TLEN Length
TURL URL
TVER Version
LOCA Location
TORG Label
Additionally, it seems that you can implement custom tags (chunks) using 4 small letters.
Maybe the main problem would be that you have to update the file header every time you change/add a chunk, but I believe this wouldn't be an obstacle for you.
Edit:Accidentally, I've found
this document, it seems that most of these tags are standartized by the EXIF specification (section 5, Exif Audio File Specification).