Newsgroups: sci.image.processing
From: paul@pcserv.demon.co.uk (Paul Carpenter)
Path: cantaloupe.srv.cs.cmu.edu!das-news2.harvard.edu!news2.near.net!news.mathworks.com!gatech!swrinde!pipex!demon!news.demon.co.uk!pcserv.demon.co.uk!paul
Subject: Re: Image file formats and compression
Distribution: inet
References: <MXM.95Apr24110841@dcs.ed.ac.uk> <3niu6p$f4a@ed.petech.ac.za> <252339006wnr@dstrip.demon.co.uk> <3nrgtn$h6u@lilith.uab.es>
Organization: PC Services
Reply-To: paul@pcserv.demon.co.uk
Followup-To: sci.image.processing
X-Newsreader: Demon Internet Simple News v1.29
Lines: 38
X-Posting-Host: pcserv.demon.co.uk
Date: Fri, 28 Apr 1995 22:03:30 +0000
Message-ID: <799106610snz@pcserv.demon.co.uk>
Sender: usenet@demon.co.uk

craig@care2.uab.es "Craig D. von Land" writes:
-Steve@dstrip.demon.co.uk (Steve Rencontre) wrote:
->...
->IMO, the only *real* need for 100% bit-for-bit accuracy is as insurance
->against being sued, as I hear is happening in the US over compressed medical
->X-rays. 
-I second that! After several years developing medical imaging systems, I've
-found that just mentioning the word "lossy" sends radiographers into fits.
-This is really unfortunate, since most medical images could handle significant
-lossy compression without loss of diagnostic information.

Some areas of x-ray and mammography, have recently had advances in the low bit
transition areas of sorting types of tissue etc.. But then you did day most.

As soon as you mention loss of quality, people build up walls, but if you just
said compression, how many even with only a little knowledge would say anything!

-The funny thing .... For example, it is
-quite common to archive digital angiography sequences onto VHS tape which
-causes a non-reversible loss of image information. Go figure!

The age old I am used to and understand VHS, (but not the limitations), and this
compression stuff is 'new', so I am resistant to it.

Anybody who does archives onto VHS as far as I am concerned cannot seriously
expect to do any real processing later. They always forget that this was 
intended as the name states for HOME use, viewability not measurability!

As in VHS = Video Home System

Personally I'd rather Very High Shit...

=-------------------------------------------------
Paul Carpenter		| paul@pcserv.demon.co.uk
PC Services		| tel (44) 1734-463634
PO Box 2030, Reading	| fax (44) 1734-463423
RG4 8YW, UK		| 
Consulting for DSP, Image processing, Data Acquisition, System tuning & more..
