It is possible to delete the folders in xterm.

However, this might lead to some unexpected problems. For example, I have most of my cover arts as cover.jpg's in the folders containing the mp3's for each album.

Well, I deleted the two mentioned folders (because some of my albums had wrong cover arts) and now I do not have any cover art left... The couple of albums and songs that have cover art embedded in the idtag do have cover art visible but the albums that have cover art as cover.jpg in the folder don't have cover art anymore.

I tried reindexing and also rebooted the device but that did not help. Does anyone have any ideas how I could get the cover to show again?

EDIT: I checked the contents of those two folders (these seem to have been recreated after reindexing):
.thumbnails/cropped have a lot of jpg's (probably for all my cover.jpg's)
.cache/media-art has just a couple of jpg's (probably the ones for songs that have album-art embedded)

So I guess that the question is: how do I get the covers also to .cache/media-art? And how do I get the contents of the .thumbnails/cropped to be visible in the Mediaplayer?

EDIT2: and the answer is: remove all .mediaartlocal -folders inside the album folders and then run tracker-processes -r. After that wait a long time and the album art should be visible again.

I have sort of the same problem. I had some wrong album art in my music folders, I removed the album covers but somehow mediaplayer is very persistent in keeping the wrong album art.

rm /home/user/.cache/media-art/*
rm /home/user/.thumbnails/cropped/*
rm /home/user/MyDocs/Music/*/.mediaartlocal/*
rm /home/user/MyDocs/Music/*/*/.mediaartlocal/*
tracker-processes -r

Did not solve the problem. Somehow somewhere the images are cached another time...

Does anyone know where all the caches are located?

got a script file like this, works for me:

my music albums being pathed like this: /home/user/MyDocs/.sounds/albums/artist - album/

http://www.xs4all.nl/~rzavelli/stuff...rackerreset.sh

to install, save the above file to the Downloads folder, then open xterm:

next, run trackerreset.sh in xterm to remove all cached data and reset the tracker.

of course you can make a desktop icon to this script, make one in /usr/share/applications/hildon/ and point it to trackerreset.sh or /usr/bin/trackerreset.sh

i've noted there is a neat app called "tracker-cfg" to reset the tracker and database using a gui. its also possible to easily set the included and excluded tracked paths with it, without manually having to edit /home/user/.config/tracker/tracker.cfg

Thanks for the advice, but I am a bit apprehensive to delete the whole .thumbnails/cache directory as there is 1500 images in there, most of which obviously don't relate to album art. Do the other thumbnails not relating to album art recreate themselves after being deleted?

yes, the whole cache will be rebuilt, except for the folders excluded in /home/user/.config/tracker/tracker.cfg

I have encountered a new strange problem when running tracker-processes -r. When the media database is rebuild some of the songs are not recognized as they should be. They are just added to mediaplayer as unknown artist/unknown album (in the end of the artist list). First I thought that I must have something wrong with the ID tags but each time that I run the command different songs are not recognized.

This is mildly irritating because these songs are ofcourse not listed in the right album and sometimes a track is just missing when playing an album...

@OVK: I have the exact same problem

What would help me with similar problems is an understanding of what the refresh in the media player is trying to do.

Does anybody know enough to give a blow-by-blow of what the media player is doing when it decides to refresh the media?

IF we could get a handle on that, we could think through why different things are happening and when certain steps are needed.

For example:
When does the media player decide it needs to re-scan the cache?
Daily?
when media player starts?
when M900 is turned on?

And then:
Once media player starts indexing, what steps does it follow?
Does it index by file names or by id3 tags?
Where does it look and which variables tell it to include/exclude a path?
Where are those files (that contain the variables) located?

If we had a description of what actually happens, we could figure out what steps are needed to fix different problems people have...

Media Player doesn't do any indexing. All media indexing is done by tracker so you'd need to look into the documentation for that.

Aaaah. I followed the instructions in this thread and now have art for only a few albums. There are no mediaartlocal folders being created for most albums even though they worked fine when I copied them in originally. Any suggestions?

Tracker is such a piece of crap. I had to laugh when I saw it was one of the things Nokia was bringing to Meego. There is a great open source python lib that can read all kinds of tags perfectly, but they had to reinvent the wheel really badly.