That was, I believe, a John Francis Explanation (tm) Shel
> [Original Message] > From: William Robb <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Date: 11/13/2004 6:26:53 AM > Subject: Re: Reducing File Size with Photoshop > > > ----- Original Message ----- > From: "Jens Bladt" > Subject: RE: Reducing File Size with Photoshop > > > > > I guess I don't understand what a jpeg compression really does! > > The way it was explained to me (probably by someone on this list). > > Imagine you have 50 identical pennies on a table top. > An uncompressed file describes each penny in detail. > A JPEG describes one penny in detail, and then tells you where the > other 49 are located on the table. > > Works well, as long as all the pennies really are identical. > It doesn't work so well when each penny is slightly different, but > still within the resolution of the descriptor. > Thats when data loss starts to be a factor. > > William Robb >
