A workaround that works pretty well for me is to tie album cover art to a dummy mp3 file which is associated with the album.
This way I am not only able to maintain per track cover art and at the same time separate cover art for the dedicated album. It is also something that I can fully control from my PC, which hosts the master library for my mobile applications, like tablet/smartphone and car audio system. No need to patch anything on Android.
The dummy file is a 1-second silent MP3 file. See attachment.
Side note: for whatever reason, the workaround does NOT work with the 8 kbit/s silence files you can find eg on github.
Important condition, as per my observations:
For album cover art, Poweramp takes the first "track 1" file, in alphabetical order (in case there be more than just one track 1 file in the album).
I'm using file names starting with "00".
This works perfect for compilations with files in %track% - %etc% as well as %artist% - %title% notations.
These are the steps to include separate album cover art for an album with individual per-track cover art:
Copy the dummy file to the album folder.
Assign a name to the file so that it is first in alphabetical order.
Tag the file:
- "Title": determines how the file appears in a track (title) list
- "Track": must be "1" (or "01") !!!
- "Artist": the album artist displayed by Poweramp in album view
- "Album": album name, which makes this file actually part of the album
- "Cover": add the desired album cover art
Done!!
Side note, and request to Poweramp folks:
When applying this method to a big library with many different "Best Of" compilations, it is almost certain that you are making errors.
I found it quite frustrating, that updating files from PC to Android, and re-creating the Poweramp library in many cases did not work to fix the problem. Poweramp seems to do caching, which survives the re-creation process.
The only method I found that worked safely, is
to move an album folder out of the music library to a temp location
wait until the change is reflected (album disappears)
update the files in the temp location
move the album back from the temp location into the music library
Would be great if next versions of Poweramp could avoid this tedious update process!
00 - Dummy.mp3