How do I compress an image, without reducing its quality? (SOLVED!!)

[blackcat12]

THIS IS SOLVED!

Right now, there's an image that I'd like to upload as an avatar on a different site, but can't because the avatar size limit for that site is 20 KB(the image is just under 70 KB). Of course, I can always save the image as a JPEG and/or make it smaller, but I don't really want to do that. Are there any other solutions?

EDIT: Also, I've tried uploading the image to ImageShack and directly linking to it, but that didn't work.

This post has been edited by blackcat12 on Jul 23 2008, 05:44 PM

[Draco Icebane]

If the image is a pixel art, save it as a GIF or PNG and cut the colors down as far as you can without losing them. (256 colors is usually sufficient.)

If the image is a pixel art with alpha channels, save it as a PNG.

If the image is a brush drawing or photograph (ie. has gradients), it is safe to save it as a JPEG and turn the quality level down until you don't think you can risk having it any lower.

[blackcat12]

Okay, it's finally solved! Thanks!