From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Mirek Kaim Newsgroups: gmane.emacs.devel Subject: RE: Image rescaling Date: Thu, 18 Sep 2014 19:03:19 +0200 Message-ID: References: , , , NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1411061329 17958 80.91.229.3 (18 Sep 2014 17:28:49 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 18 Sep 2014 17:28:49 +0000 (UTC) Cc: "emacs-devel@gnu.org" To: Lars Magne Ingebrigtsen Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Sep 18 19:28:42 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XUfVX-0001Q0-Ow for ged-emacs-devel@m.gmane.org; Thu, 18 Sep 2014 19:28:39 +0200 Original-Received: from localhost ([::1]:52407 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUfVX-0005k0-9Z for ged-emacs-devel@m.gmane.org; Thu, 18 Sep 2014 13:28:39 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:48190) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUfV9-0005c5-8c for emacs-devel@gnu.org; Thu, 18 Sep 2014 13:28:20 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XUfV3-0008Kj-Cz for emacs-devel@gnu.org; Thu, 18 Sep 2014 13:28:15 -0400 Original-Received: from col004-omc2s10.hotmail.com ([65.55.34.84]:51509) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XUfV3-0008JE-7z for emacs-devel@gnu.org; Thu, 18 Sep 2014 13:28:09 -0400 Original-Received: from COL131-W12 ([65.55.34.72]) by COL004-OMC2S10.hotmail.com with Microsoft SMTPSVC(7.5.7601.22724); Thu, 18 Sep 2014 10:03:20 -0700 X-TMN: [5h6E0lNq1MS9AT3PbfPVH+mhr7cIlJWkov90UzqjICE=] X-Originating-Email: [mirek.kaim@outlook.com] Importance: Normal In-Reply-To: X-OriginalArrivalTime: 18 Sep 2014 17:03:20.0285 (UTC) FILETIME=[72C5B8D0:01CFD362] X-detected-operating-system: by eggs.gnu.org: Windows 7 or 8 [fuzzy] X-Received-From: 65.55.34.84 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:174512 Archived-At: > From: larsi@gnus.org=0A= >=0A= > Mirek Kaim writes:=0A= >=0A= >> convert to hsl=2C rescale using bilinear (should be fine for a start)=2C= =0A= >> convert back to rgb? that should do the trick i guess. and it should=0A= >> be pretty fast and easy to implement. unic0rn=0A= >=0A= > Yeah=2C looks pretty easy. When rescaling to a smaller size=2C some kind = of=0A= > blurring (Gaussian seems popular) has to be done first=2C apparently.=0A= =0A= that wouldn't be bilinear anymore i guess. sure=2C gaussian or lanczos=0A= could be implemented=2C but for a fast start bilinear or perhaps bicubic=0A= should be sufficient. doing it in hsl colorspace should prevent artifacts= =2C=0A= and the whole thing will be pretty small and easy to code.=0A= =0A= unic0rn=0A= =0A= ps. i hope my email won't end up in one line this time=2C=0A= no idea what the hell happened last time :/=0A= =0A= =