Comment 3 for bug 1598968

Victor: are you sure this is a thumbnailer problem?

When playing around with music-app, the one place where large cover art is displayed is in the "now playing" screen. Looking at the source code, this corresponds to NowPlayingFullView.qml:

http://bazaar.launchpad.net/~music-app-dev/music-app/trunk/view/head:/app/components/NowPlayingFullView.qml

That code shows an intentionally blurred background image, with a CoverGrid over the top showing the album art. Looking at CoverGrid.qml, you're requesting thumbnails of at most 512x512:

http://bazaar.launchpad.net/~music-app-dev/music-app/trunk/view/head:/app/components/CoverGrid.qml#L68

On devices with high resolution screens like the Meizu MX4, this looks like it is going to be blowing up a down scaled version of the artwork.