I'm sure that most readers of this forum understand all this, but I thought that I'd write this up in case any of this is of any use to anyone.
When I set up my Rune Audio system I copied the .mp3 and .m4a files from my iTunes library to /mnt/MPD/SD. I then found that it took about half a second for Rune Audio to list the contents of an album (this is a pi 3B), the reason being that it is programmed to do the following until it succeeds in finding album art:
- 1. Search for an album art file in the same directory as the music files. (It looks for any of the following: cover.jpg, cover.png, folder.jpg, folder.png, front.jpg, front.png.)
2. See if there is any album art in one of the music files. This uses kid3-cli which takes about 300 ms to run, even if there is no album art in the specified music file.
3. Query ws.audioscrobbler.com to look for album art.
Even after all that, it would frequently find no album art for many of the albums in my collection.
So I figured that based on the above, the best way to speed this up would be to copy across album art files for the albums. I found that on my iTunes system (Windows), a lot of the directories contained a hidden system file called Folder.jpg, which indeed contains artwork for the album in question. Because it's a hidden system file, by default it's not visible in File Explorer or if you run 'dir' at a command prompt, but it
is listed if you run 'dir /a'. You can remove the 'hidden' and 'system' attributes from the files by running 'attrib -s -h <path>\Album.jpg', and then copy them across to /mnt/MPD/SD. After that, I found that listing an album took more like 150 ms (and artwork is shown for many more of my albums), so I was delighted with the improvement.
Vaughan
