I'm not sure if there's already a post about something similar to this, but I couldn't find anything that helped me figure it out so I'll post this. As you may know, Google really messed up with making the album artwork's resolution sharp like they probably are on your computer, but instead really blurred and pixelated. It can be extremely annoying. So today I think I might have found a solution. Please keep in mind I have a Droid RAZR and I'm not positive this will work for other phones, but it most likely will. Note that I also use Play Music.
First, you want to connect you phone to your computer and select "USB Mass Storage" or "PC Mode" and open up the "Android" file folder on your computer then opening "data". You'll come to a list of files with the prefix "com". You'd want to click on the file named "com.android.providers.media" followed by "albumthumbs". It'll bring you to a list of files with no extensions. Those are the incredibly low quality album covers. When you try and open them, Windows will ask you what you want to open it with, you can just choose Windows Photo Viewer. But make sure the little check on the lower left of the window is unchecked. I unfortunately have no photos of the low-resolution photos since I already changed them all. But you will see the very blurry, pixelated cover art. What you want to do then is find the high-resolution matching cover art (I just Google it and find the highest square resolution), rename it to the low-resolution file, then drop it in and choose "Move and Replace". Repeat that process for the following files. Then simply close out, eject the device, and enjoy sharp, clean album covers.
Let me know if you need something explained or if there are any issues!
First, you want to connect you phone to your computer and select "USB Mass Storage" or "PC Mode" and open up the "Android" file folder on your computer then opening "data". You'll come to a list of files with the prefix "com". You'd want to click on the file named "com.android.providers.media" followed by "albumthumbs". It'll bring you to a list of files with no extensions. Those are the incredibly low quality album covers. When you try and open them, Windows will ask you what you want to open it with, you can just choose Windows Photo Viewer. But make sure the little check on the lower left of the window is unchecked. I unfortunately have no photos of the low-resolution photos since I already changed them all. But you will see the very blurry, pixelated cover art. What you want to do then is find the high-resolution matching cover art (I just Google it and find the highest square resolution), rename it to the low-resolution file, then drop it in and choose "Move and Replace". Repeat that process for the following files. Then simply close out, eject the device, and enjoy sharp, clean album covers.
Let me know if you need something explained or if there are any issues!