From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.comp.tex.context/13991 Path: main.gmane.org!not-for-mail From: Siep Kroonenberg Newsgroups: gmane.comp.tex.context Subject: Re: Dithering (off-topic) Date: Fri, 31 Oct 2003 16:17:36 +0100 Sender: ntg-context-admin@ntg.nl Message-ID: <20031031151736.GA1249@bitmuis.thuis.nl> References: <3FA245CC.30502@econ.muni.cz> Reply-To: ntg-context@ntg.nl NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1067624528 4278 80.91.224.253 (31 Oct 2003 18:22:08 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Fri, 31 Oct 2003 18:22:08 +0000 (UTC) Original-X-From: ntg-context-admin@ntg.nl Fri Oct 31 19:22:06 2003 Return-path: Original-Received: from ref.vet.uu.nl ([131.211.172.13] helo=ref.ntg.nl) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1AFduQ-0007Fn-00 for ; Fri, 31 Oct 2003 19:22:06 +0100 Original-Received: from ref.ntg.nl (localhost.localdomain [127.0.0.1]) by ref.ntg.nl (Postfix) with ESMTP id 022CB10B20; Fri, 31 Oct 2003 19:22:00 +0100 (MET) Original-Received: from dep.oprit.rug.nl (dep.oprit.rug.nl [129.125.36.9]) by ref.ntg.nl (Postfix) with ESMTP id 7242C10B20 for ; Fri, 31 Oct 2003 16:18:11 +0100 (MET) Original-Received: from client44-3.kabela.oprit.rug.nl (client44-3.kabelA.oprit.rug.nl [129.125.44.3]) by dep.oprit.rug.nl (8.12.10.Beta2/8.12.10.Beta2) with SMTP id h9VFI60A013841; Fri, 31 Oct 2003 16:18:10 +0100 (MET) Original-Received: by client44-3.kabela.oprit.rug.nl (sSMTP sendmail emulation); Fri, 31 Oct 2003 16:17:36 +0100 Original-To: ntg-context@ntg.nl Content-Disposition: inline In-Reply-To: <3FA245CC.30502@econ.muni.cz> User-Agent: Mutt/1.4i Errors-To: ntg-context-admin@ntg.nl X-BeenThere: ntg-context@ntg.nl X-Mailman-Version: 2.0.13 Precedence: bulk X-Reply-To: Siep Kroonenberg List-Help: List-Post: List-Subscribe: , List-Id: mailing list for ConTeXt users List-Unsubscribe: , List-Archive: Xref: main.gmane.org gmane.comp.tex.context:13991 X-Report-Spam: http://spam.gmane.org/gmane.comp.tex.context:13991 On Fri, Oct 31, 2003 at 12:21:48PM +0100, Michal Kvasnicka wrote: > Good evening. > > I apologize to ask a little off-topic question, but I don't know where > to ask (and it is closely related to TeX and PDF). > > I typeset a church bulleting. It is printed on a laserjet printer (600 > dpi), and then copied on a copy machine. As for letters, all is right. > But figures (photos) are this way spoiled. I guess it would help either > to force PDF to print the figures in some very low resolution (150 dpi), > or (probably better) to dither the figures and include them in PNG > (instead of ordinary JPEG). Can some of you tell me how to do it? I > tried ImageMagick's convert to dither the photos, but outcomes were > really poor. Is there some good free software for this (in the best case > in Linux)? Or can I do it some way in PDF? > > Many thanks for any hint. > Michal Kvasnicka A PostScript solution: create a dvips header file for course rasterization: %! /bop-hook {53 45{dup mul exch dup mul add 1. exch sub}setscreen} def These numbers (raster frequency and angle) are probably ok for 600dpi; otherwise, experiment a bit. Call it coarse.pro and give dvips a parameter -h coarse.pro -- Siep Kroonenberg siepo@cybercomm.nl