Embedding jpgs in id3 tag?

[Project Epsilon]

ok, so i recently got a psp, and i'm loving the thing. and i finally got a usb cable so i could stuff all my mp3s and videos on it. well, while scrolling my list of songs on my psp, i noticed that instead of a little square beside the track title with a number on it, one of my songs had a pic of the album cover on it. doing some research i found out that you can embed a image in the id3 tag. and thats where my questions come from :

1- what is a good proggy for linux to embed album art in the id3? i've found some, but i'm looking for one that i can embed the images in my current library without re-ripping.

and

2- If i use a program to embed the pic, it won't mess with the mp3 itself, right? basically, it wont re-encode the song or anything and degrade the quality. from my understanding the id3 tag is sorta separate from the audio? or am i wrong?

much thanks in advance for the advice!

[Proto]

Well, I dunno, but this program seems to do what you ask for, best of all it integrates with Nautilus

2. No, the id3 is stored separately from the audio file itself.