If I *was* the one to introduce it to this list, I was only re-posting something I found elsewhere; it wasn't original with me.
I'd like to take credit for it - it's a wonderful analogy - but real credit belongs elsewhere. Shel Belinkoff mused: > > 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 > > > >
