Path: csiph.com!usenet.pasdenom.info!aioe.org!rt.uk.eu.org!feed.xsnews.nl!border-2.ams.xsnews.nl!feeder.xennanews.com!nf38.xennanews.com!not-for-mail From: Cecil Westerhof Newsgroups: comp.lang.postscript Subject: Re: Sometimes noise and resources about colours Organization: Decebal Computing References: <87r4nhl5on.fsf@Compaq.site.inet> X-Homepage: http://www.decebal.nl/ Date: Sun, 25 Nov 2012 23:54:43 +0100 Message-ID: <87ip8tl2do.fsf@Compaq.site.inet> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux) Cancel-Lock: sha1:XRdP8wUTZhYKntTVY08/A/QPRqM= MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@xennanews.com Lines: 68 NNTP-Posting-Host: 84.53.123.169 (84.53.123.169) NNTP-Posting-Date: Sun, 25 Nov 2012 23:59:25 +0100 Xref: csiph.com comp.lang.postscript:1087 Op zondag 25 nov 2012 23:03 CET schreef Chris: >> I am dabbling with postscript. I like it, but it take a lot of time. ;-) >> >> The last 6 graphics at: >> https://www.facebook.com/media/set/? > set=a.351549161549364.70328.100000828491269 >> >> (the first 6 in the list) I made with postscript. But I see some noise >> in some of them. How can I circumvent this. At the moment I use ps2pdf >> to make an pdf and then convert (from Image Magick) to make a png. I saw >> that it is in principal possible to make a png with ghostscript. Would >> that give better results. > > I assume the "noise" you refer to are the "blobs" around the text > glyphs. Yes. > That looks to me like the effects of halftoning, because the output > doesn't have enough colours to accurately portray the colours you've used > in the Postscript. But I am only using two colours. > Using ImageMagick, you almost certainly already are using Ghostscript, > but you will have more direct control by calling Ghostscript directly, > and you can leave out the ps2pdf step. > > You can do something like: > gs -sDEVICE=png16m -r300 -o .png .ps The first try does not look promising. With the -r300 I get a to big picture. When I leave it out the size is correct. But I still have the noise. Also the kerning is wrong. The letters are to close together now. The command I am using is: gs -sDEVICE=png16m -o keepYourHead2.png keepYourHead.ps The 2 is to keep the file from the other generate to compare them. The generated files are posted at: http://decebal.nl/postscript/keepYourHead.png http://decebal.nl/postscript/keepYourHead2.png > You can also replace "png16m" with png16, png256, png48, pngalpha, pnggray > or pngmono, for different colour fidelities (lower fidelity == smaller > file size). The "-r" (resolution) option is something you probably want > to read up on. > > Most of the commonly used Ghostscript options are documented here: > http://www.ghostscript.com/doc/9.06/Use.htm I'll look into them. By the way, I even see noise in the pdf, but less and only under the text: http://decebal.nl/postscript/keepYourHead.pdf -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof