AAC files using M4A wrapper not loading properly

[mortgagemetrix]

AAC files are not scanned properly. Most encoders save AAC audio in the M4A wrapper but Musticpod does not recognize these files. If I manually change the file extension to MP4, the file is recognized and able to be played. MP4 wrapper extension is typically used for video, not audio files.

[Feichtmeier]

AAC files are not scanned properly. Most encoders save AAC audio in the M4A wrapper but Musticpod does not recognize these files. If I manually change the file extension to MP4, the file is recognized and able to be played. MP4 wrapper extension is typically used for video, not audio files.

hmmmm, well
the library I use for reading metadata supports flac, mp3, ogg, opus and mp4
Sure I could add more allowed file extensions but then the music files are just loaded with there file types
generally the local audio feature of musicpod (remember radio and podcasts have the same prio) is designed around users with tagged libraries. I don't want to tap into this gray area of creating some database of "might be the right info" for each file, just because people dont buy music anymore. (mp3 downloads have everything tagged perfectly)

anyways, do you know if aac files have metadata?

[mortgagemetrix]

No, M4A (a file format for AAC audio encapsulated in MP4) does not use ID3v2 tags for metadata. Instead, it uses MP4 metadata atoms, which are part of the ISO Base Media File Format (commonly used for MP4 files).

FYI, Quod Libet doesn't really get this right either. It correctly maps ©ART to TPE1 but treats aART as distinct from TPE2, mapping aART to Album Artist and TPE2 to Performer. iTunes and Picard both treat these tags as interchangeable.

Key Differences
ID3v2 Tags:

• Used in formats like MP3.
• Organized into "frames" (e.g., TPE1, TALB, etc.).
• Typically placed at the beginning of the file.

MP4 Metadata Atoms:

• Used in M4A, MP4, and similar formats.
• Organized into "atoms" (e.g., ©ART, ©alb, aART).
• Embedded within the file structure.

MP4 Atom	Description	ID3v2 Equivalent
©ART	Artist	TPE1
©alb	Album	TALB
aART	Album Artist	TPE2
©nam	Track Title	TIT2
trkn	Track Number	TRCK
disk	Disc Number	TPOS
©gen	Genre	TCON
©day	Year	TYER
soar	Sort Order for Artist	TSOP
soaa	Sort Order for Album Artist	TSO2
soal	Sort Order for Album	TSOA
sonm	Sort Order for Track Title	TSOT