Message-Id: <mailto:199607080428.XAA18115@library.wustl.edu> Date: Sun, 7 Jul 1996 21:23:46 -0700 From: Paula Berinstein <mailto:paulab@NETCOM.COM> Subject: Re: Lossy compression files larger? To: Multiple recipients of list IMAGELIB
Kurt Foss said:> I suspect potential changes in file size would be the lesser concern over
> increasingly degraded image quality with repeated JPEG compression *if* the
> level of compression or other content-impacting factors were successively
> changed. Repeated saving of JPEG files at the original compression ratio
> seem to have no impact on size or image degradation from the occasional
> tests I've seen done by Storm Technology folks a few years ago. What would
> be the reason for successive compressions in the situations you're
> postulating? Seems it's always good to have a non-JPEGed original for
> situations where varying compression ratios might be required.
>
Kurt,Right you are that quality is a more important factor than file size. My question was theoretical and based on curiosity only, not any practical consideration. In practice, one would probably not want to compress and recompress, but it intrigued me that if you did, you might end up with a larger file at some point, and I was wondering how that could be so.
Paula
Paula Berinstein Berinstein Research Woodland Hills, CA (818) 704-6460