GNOME Bugzilla – Bug 318376
JPEG saving ignores original quality
Last modified: 2006-12-07 21:55:10 UTC
Distribution/Version: SuSE Linux 10.0 1. Have a 5MB JPEG Super Fine Quality JPEG from camera. 2. Apply Red eyes Now compare sizes of original and changed file. It has about half size and there is not chance to save "nearly original quality". For example of program, which is able to guess JPEG quality, you can use jpegdump (from Tom Lane).
this is a good point I'll take a look at jpegdump
There is an alternative way of improving of small areas of jpeg image implemented in the jpegpixi program. It recompresses only areas where change was done and does verbatim copy of compressed data of the rest of the image. Maybe it can be applied for red eyes, too. http://www.zero-based.org/software/jpegpixi/
ah, that is very cool, I'll definitely look into it as well
Any news on this one?
Just downloaded and had a look at the jpegdump code. Before working with this, I'm wondering if the licence is compatible with the GPL. Here's the copyright notice: <snip> Copyright (c) 1992 Handmade Software, Inc. by Allan N. Hessenflow Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. This software is provided "as is" without express or implied warranty. <snap> The 'without fee' thing could not be compatible with the GPL...
Perhaps check with the author? Perhaps he can change to GPL?
jpegpixi as suggested in comment #2 is released under GPL though :)
jpegpixi could (probalby) be used for red-eye removing. But for color correction, sepia tones, lossy cropping, ... it should be great to guess the compression factor. I try to contact the author of jpegdump, asking if he could release it under gpl or lgpl... wait and see...
Created attachment 66658 [details] [review] jpegdump for f-spot Here is a small patch (1000+ lines) adding the ability to guess the compression factor used for a jpeg. You can use it like this: JpegUtils.GuessQuality(filename) It includes a lot of code from jpegdump, which is *NOT* in GPL (waiting for feedback from the author). I'm not planning to write code here and there in f-spot for supporting this before having news from the original author of jpegdump. Nevertheless, you can already review it. (just add a call to that code somewhere in f-spot). Some technical informations: - new libjpegdump directory with the modified tool - binding in libfspot - binding to libfspot in JpegUtils.cs
Just received (so did Larry) a mail from the author of jpegdump: <snip> Yes, I am hereby granting permission to release jpegdump under the GPL. allan -- Allan N. Hessenflow <snap>
Ugh, I meant to have this in by now, I have a version of the extracted guessing code in my tree. I'll try to get it finished today.
ok I've committed the ported guess quality code to JpegHeader but haven't hooked it up to any of the saving functions.
Larry, very good job ! I've also started to port the code to C#, but you were quicker !
*** Bug 350301 has been marked as a duplicate of this bug. ***
now that the guessing code I'll dig up my old patch to use the guess when saving a new version.
Fixed in CVS by Larry yesterday... closing it.