SD Card and Library - MrTartuf0/onda-flac-player GitHub Wiki

Preparing the card

  • Format it as FAT32 (exFAT works too).
  • Organise folders however you like, for example Music/Artist/Album/01 - Title.flac. The whole card is scanned.
  • Only .flac files are played. Playlists (.m3u / .m3u8) can be anywhere on the card.

You can copy files with a card reader or over Wi-Fi from a browser (see Web Interface).

Indexing

On the first start the player reads every file and shows a progress bar (looking for files, reading tags, preparing covers, saving the index). After that it starts in a moment: only new or changed files are read again.

If you add music with a card reader, the new files are picked up at the next start, or right away with Settings → Update library. After a Wi-Fi transfer the library is updated when you leave the transfer screen.

The player keeps its index, cover thumbnails, likes and play counts in the hidden folder /.onda on the card. You can delete it at any time; it is rebuilt (but likes and play counts are lost).

Tags

onda reads standard Vorbis comments, the same tags every FLAC tagger writes:

Tag Used for
TITLE Song title (if missing, the file name is used)
ARTIST Song artist (if missing: Unknown artist)
ALBUM Album (if missing, the folder name; files in the root of the card go to Single tracks)
ALBUMARTIST Groups an album across folders and names its artist
TRACKNUMBER, DISCNUMBER Song order inside an album
DATE Year shown on the album page
GENRE Genre browsing (one genre per song, the first GENRE tag)

How albums are grouped:

  • with ALBUMARTIST: same album title + same album artist, even in different folders;
  • without it: same album title in the same folder. If the songs have different artists, the album artist becomes Various artists.

Missing tags are easy to fill in from the web page, by hand or automatically from MusicBrainz. Its Libreria (Library) tab has a Dati mancanti (missing data) filter.

Covers

For each album the player uses, in this order:

  1. a cover.jpg in the album folder;
  2. the picture embedded in the FLAC files;
  3. another image in the folder: folder.jpg, front.jpg, album.jpg, albumart.jpg, then any .jpg.

Covers must be baseline JPEG. PNG and progressive JPEG are not decoded on the device and show a placeholder instead. The web page fixes this in one go: Libreria → Sistema copertine (fix covers) converts unreadable embedded covers to a 600 px cover.jpg in each album folder.

The album colour used for the now-playing gradient is computed once from the cover and cached.

Playlists

Any .m3u or .m3u8 file on the card becomes a playlist. Paths can be relative to the playlist file or absolute from the root of the card. Playlists made in the web page are saved in /Playlist. They appear under Search → Playlist after the library is updated.

Liked songs and All songs are built-in playlists, always the first two tiles on the Home screen.