[Gimp-developer] Lanczos algorithm matrix
Hi, I had just decided to try using a sinc function to remove pixelisation. I did a bit of research googled the mailing lists (well everywhere in fact) but did not find much. I decided to open and image in Gimp and expand it an try a few values in a convulution matrix. To my frustration it got automatically smoothed. I soon found the interpelation = none option and tried the other options. I'd not heard of Lanczos Best before so I googled and found out it was the sinc I was trying to do! Nice work, preemptive development. ;) It seems pretty good on the tests I did although arguably whether it is better or worse than cubic on my data. Different sure. I think best is subjective and depends on the nature of the image. There was on overall sharpness better than cubic but more aritifacts. This surprised me a bit so I started looking at the code to see if I could determine the parameters and maybe experiment a bit to improve it. Due to the size of Gimp and the abstraction of all these things going through pdb etc, I did not find all I wanted. However, it did seem that all these resize/rotations etc were operated on a 3x3 matrix and that this dimension is hardcoded. Could s.o. correct me if I misread that , but it seems to explain why sinc is not giving better results than cubic. If that is the case the complex sinc fn is being represented by only 3 data points (in 1D). While 3 data points may describe a simple cubic interpollation reasonalby well . It in no way represents the complexity of sinc, and so all the F.T. theory behind it falls flat. My aim is to try a larger matrix for sinc. Could someone point me to where kernel is calculated for sinc and confirm my impression that the resize is fixed to operate on 3x3? Thanks for any clues. I will save a lot of digging. regards. GG. ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
[Gimp-developer] Re: Lanczos algorithm funnyness?
Hi, I know this is rather old but it still seems pertinent. Now that lanczos is firmly in place and seems to work pretty well this probably should be addressed. It seems to me the there is a fundemental analytical difference between expand and reduce even tho' the two can be presented on the same %age input, does this make sense? Either the list of interpolation methods needs to swap about depending on the % value entered or two different dlgs are needed. Image|Expand and Image|Reduce. I suggest the latter solution is preferable. This would present the user with clearer choises and technically correct, better performing filters could be applied to reduction. It seems a user would choose to either increase or decrease an image. One or the other. How much bigger/smaller is a continuous scale but the choice of direction is binary. The coding is presumably fairly straightforward bit it seems a different set of choices are needed for reduction. best regards, GG ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] easier way to convert image into selection
Hi, On Fri, 2006-09-15 at 09:39 +0930, David Gowers wrote: It's much easier to code 'image to selection': c = pdb.gimp_channel_new_from_component(image, GRAY_CHANNEL, 'TEMP IMAGE2SELECTION') This works for grayscale images only. An RGB image doesn't have a grayscale component. For grayscale images there is also no point in writing such a script because you can already choose Channel to Selection from the channel's right-click menu. Sven ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Lanczos algorithm matrix
Hi, On Sun, 2006-09-17 at 09:01 +0200, [EMAIL PROTECTED] wrote: It seems pretty good on the tests I did although arguably whether it is better or worse than cubic on my data. Different sure. I think best is subjective and depends on the nature of the image. The term Best has already been removed from the GUI. Are you not working with CVS? You definitely should as the Lanczos code is still undergoing changes. Please also have a look at http://bugzilla.gnome.org/show_bug.cgi?id=167956 http://bugzilla.gnome.org/show_bug.cgi?id=355178 We could definitely need some help to fix these issues so that the Lanczos option can remain enabled for the upcoming GIMP 2.4 release. Sven ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Gimp python
Hi, On Wed, 2006-09-13 at 10:31 +0200, Sven Neumann wrote: the internationalisation of the Gimp Python bindings and plug-ins is still pending: http://bugzilla.gnome.org/show_bug.cgi?id=351287 We have come a good deal further here in the meantime. The framework for internationalisation is now in place. What's missing is the review of the strings (basically the same job as what's needed for Script-Fu, only much fewer strings) and marking them for translation. Any volunteer who wants to go over the python plug-ins, check that the strings are OK and that the procedure blurbs have the same style as what is used by the plug-ins? The files to look at are (from the plug-ins/pygimp/plug-ins folder): clothify.py colorxhtml.py foggify.py happy-valley-relief.py palette-offset.py palette-sort.py palette-to-gradient.py pdbbrowse.py py-slice.py shadow_bevel.py This list does intentionally leave out plug-ins that are already internationalized or are not installed in a stable release and are only included as examples. Sven ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: Lanczos algorithm funnyness?
From: [EMAIL PROTECTED] Thanks for your ideas. If you want to play around with Lanczos, you might benefit by looking over the enhancement requests and bug reports relating to it: Bug 162250 Feature Request: Better image scaling algorithms. http://bugzilla.gnome.org/show_bug.cgi?id=162250 Bug 343576 Lanczos resize not the best http://bugzilla.gnome.org/show_bug.cgi?id=343576 Bug 167956 scaling image causes an offset, particularly with Lanczos http://bugzilla.gnome.org/show_bug.cgi?id=167956 Bug 355178 transformation tools with Lanczos interpolation brighten the result http://bugzilla.gnome.org/show_bug.cgi?id=355178 The Lanczos algorithm does not use a 3x3 matrix. The code for Lanczos lives in two places: app/paint-funcs/scale-funcs.c -- for the scale image and scale layer commands app/core/gimpdrawable-transform.c -- for the transform tools As Sven pointed out, this code has been changing pretty rapidly in an effort to make it robust enough for inclusion in the upcoming 2.4 release, so it would be best to look at cvs HEAD if you want to avoid seeing things that are already obsolete. -- Bill __ __ __ __ Sent via the CNPRC Email system at primate.ucdavis.edu ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] easier way to convert image into selection
On 9/17/06, Sven Neumann [EMAIL PROTECTED] wrote: Hi,On Fri, 2006-09-15 at 09:39 +0930, David Gowers wrote: It's much easier to code 'image to selection': c = pdb.gimp_channel_new_from_component(image, GRAY_CHANNEL, 'TEMP IMAGE2SELECTION') This works for grayscale images only. An RGB image doesn't have agrayscale component. For grayscale images there is also no point inwriting such a script because you can already choose Channel to Selection from the channel's right-click menu.I tested it for RGB images and it appears to work correctly.Perhaps it just uses the 1st channel (R) though. ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
[Gimp-developer] Adobe Illustrator to GIMP palette converter
Hello everyone, This is my first ever GIMP related programming project. I've written a stand-alone converter for Adobe Illustrator palette files (.ai) to GIMP palette files. This was written because I do vinyl cutting/signs and the various makers of the vinyl (Avery etc) produce palette files based on their available colours. Clearly it's advantageous/simpler to use their palettes rather than trying to go through the whole spot matching process. Anyhow, the program is about 5K in size and available in C source code format at; http://pldaniels.com/gimp It's Revised-BSD licenced so you can fairly much do anything you like with it and it is GPL compatible. Regards. -- PLDaniels - http://pldaniels.com - Xamime email content filtering PGP Public Key - http://pldaniels.com/gpg-keys.pld Pet Luxuries - http://pet-luxuries.com R/C Gear Shop - http://nqrc.com A.B.N. 19 500 721 806 ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] easier way to convert image into selection
From: Alexander Rabtchevich [EMAIL PROTECTED] Some plug-ins (edge detection for example) provide images as a result. If their result is required as a selection, I new only one way to make it: create layer mask, copy the image into the mask and convert the mask into selection. Is there a shorter way to do it? I wrote a Script-fu which performs something similar: it converts the image contents of the current selection into the selection. The selection created only includes the pre-existing selection, so perform a Select None or Select All before executing the command if you wish the entire layer to be converted into a selection. (Note: the command also works with layermasks and channels.) The function appears on the Select menu as From Drawable. ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
Re: [Gimp-developer] easier way to convert image into selection
It would probably help if I provided a link to the script. :-) http://flashingtwelve.brickfilms.com/GIMP/Scripts/layer-select.scm Also, the file includes another function (which selects the boundaries of the active layer). ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
[Gimp-developer] GIMP 1.2 support removed from Gutenprint 5.1 mainline
I've removed the GIMP 1.2 support from the Gutenprint mainline per plan. Gutenprint 5.1 and beyond will only support GIMP 2.0 and above. -- Robert Krawitz [EMAIL PROTECTED] Tall Clubs International -- http://www.tall.org/ or 1-888-IM-TALL-2 Member of the League for Programming Freedom -- mail [EMAIL PROTECTED] Project lead for Gutenprint --http://gimp-print.sourceforge.net Linux doesn't dictate how I work, I dictate how Linux works. --Eric Crampton ___ Gimp-developer mailing list Gimp-developer@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
