How do I know if art is embedded?
Embedding art in mp3s has many advantages. But how do you know if art is already embedded in your music collection?
One way is to use a tag editor. Tag editors (or sometimes just 'taggers') are software that display the internal tags stored inside MP3s and other music files. Embedded album art is just another one of these tags, and so most MP3 tagging software will show any album art already embedded in your files. I recommend Mp3tag for Windows and puddletag or EasyTAG for Linux.
An alternative is to use bliss to assess your music for embedded art. Once your music has been scanned and assessed by bliss you will be told whether art is embedded or not. At the same time, bliss will also automatically embed any art that you already have or any art found on the Internet.