[MPlayer-users] Are mencoder lossless codecs really lossless?

[James Board]

Maybe I should explain why I'm trying to encode to lossless, and then back to the original format.  It's only to prove that the lossless codecs really are lossless (when I first tried to go from raw->lossless->raw, my file size decreased by 25% which made me wonder).
 
The whole point is I want to encode several video files, but I'm new to this process, at least with the current tools.  I haven't figured out how to best deal with telecining, inverse telecining, de-interlacing, and other issues.  So I'd like to keep my raw AVI capture files around for a while so that if I later figure out a better way to encode, then I still have the raw captured video.  But this is HD Video and the raw capture  files are about 450 GB per hour.  I don't have enough disk space to keep more than a few of them.  So, that's why I looked into the lossless encoders: so I can keep the raw capture files.  But if the lossless encoders aren't really lossless, then there's no point in doing this.  I'd have to recapture again.  So that's whay I'd like to know if they are really lossless, or if that's just a common industry term (like de-cafinated) and it doesn't really mean lossless.  Does that better explain things?