Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.albasani.net!weretis.net!feeder4.news.weretis.net!feeder2.ecngs.de!ecngs!feeder.ecngs.de!Xl.tags.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!local2.nntp.ams.giganews.com!nntp.brightview.co.uk!news.brightview.co.uk.POSTED!not-for-mail NNTP-Posting-Date: Thu, 23 Jun 2011 01:56:05 -0500 From: ken Newsgroups: comp.lang.postscript Subject: Re: PDF: multiple slides per page to one slide per page? Date: Thu, 23 Jun 2011 07:56:01 +0100 Message-ID: References: <7d554826-c2b6-4dff-a363-8e8bf16c6798@r19g2000prm.googlegroups.com> <49e8cf9b-1625-462f-b3dd-eddfec9dfd66@y7g2000prk.googlegroups.com> <1d724167-c700-4c97-809e-db7ffa3d23d3@r33g2000prh.googlegroups.com> Reply-To: ken@spamcop.net MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 8bit User-Agent: MicroPlanet-Gravity/3.0.4 Lines: 32 X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-8F3ueLHRj0G2rlXVDCKZXqaLpBE9TWv1G3OR8cZe/l5skSnckzdr8R0SzR2NSRBiN89OPa+v8lTkZSO!VKvlOztZRai03nFs1UiiyftkGI6IuqJDzueERmRE0GBqCXknD98++QmHAY0eOG2MooCbCot53gUg!CJ3d7wmoyCQilsmG X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2465 Xref: x330-a1.tempe.blueboxinc.net comp.lang.postscript:258 In article <1d724167-c700-4c97-809e-db7ffa3d23d3 @r33g2000prh.googlegroups.com>, dmathog@gmail.com says... > > On Jun 21, 3:03 pm, David Mathog wrote: > > > > > The only thing I can't quite figure out is why the quality of images > > degrades. > > Here are two screen dumps taken at (about) the same resolution showing > the image > degradation: > > http://saf.bio.caltech.edu/pub/pickup/platonic_original.PNG > http://saf.bio.caltech.edu/pub/pickup/platonic_flate.PNG I don't see image 'degradation', the shapes of the letters look the same. What I do see is a difference in the colours of the pixels, which suggests either a decoding difference (the image looks to have been a JPEG initially), or a difference in colour conversion. Colour conversion should not be taking place for a PDF output, so the most likely difference is something to do with JPEG decoding. You could try using Ghostscript to render the originsal PDF file to CMYK and RGB, and look at the output to see if the result looks the same. You haven't said which version of Ghostscript you are using either, if you are using an older version you could try upgrading. Ken