Search found 64 matches

by brodriguez
Sat May 08, 2010 12:20 pm
Forum: Miscellaneous
Topic: Ximagic Quantizer
Replies: 119
Views: 28526

Re: Ximagic Quantizer

Yes, I can confirm it :(

There is a bug in the octree method. The problem appears with less than 8 colors, with or without error diffusion and with or without 2-pass.

Thanks for the feedback, I'll work on this bug asap.
by brodriguez
Tue Apr 27, 2010 2:31 pm
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

When creating 45º halftones from the built-in list, what mesh motive is used? I mean is the halftone made up of round dots, elliptical, square, or what? Photoshop CS3's built-in halftone mode allow you to choose forms from Round, Elliptical, Square, Cross, Lines... The halftones in the built in lis...
by brodriguez
Mon Apr 05, 2010 1:17 am
Forum: Miscellaneous
Topic: Ximagic Quantizer
Replies: 119
Views: 28526

Re: Ximagic Quantizer

2. lloyd algorithms is defined for greay-scale images? What algorithm did you implemented in your package for color images? The K-means algorithm (or Lloyd's) http://en.wikipedia.org/wiki/K-means_clustering can be used in any n-dimensional space, you just needs a function which give you the distanc...
by brodriguez
Mon Apr 05, 2010 12:21 am
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

Can Hilbert-Peano curves (i.e. Riemersma) be considered some form of FM-Screening (stochastic) or are they a different thing? I suppose your question is about hilbert-peano used in error diffusion dithering. When the halftoning algorithms are classified into FM, AM and hybrid FM-AM, the error diffu...
by brodriguez
Sun Apr 04, 2010 11:51 am
Forum: Miscellaneous
Topic: Ximagic Denoiser Plugin
Replies: 19
Views: 8990

Re: Ximagic Denoiser Plugin

Hello Then, there appears heavy pink artifacts at the bar code. Is this normal? More o less, it is something that happen in older versions, but I think I solved it. This image shows I didn't and I must work on it again. :( The issue only happen using the enhanced version. Also, If you disable the en...
by brodriguez
Wed Mar 03, 2010 1:21 am
Forum: Miscellaneous
Topic: Ximagic Denoiser Plugin
Replies: 19
Views: 8990

Re: Ximagic Denoiser Plugin

Starting with version 2.9.0 the installer is no longer needed for the MP version. :D
by brodriguez
Fri Jan 29, 2010 1:37 am
Forum: Miscellaneous
Topic: Ximagic Denoiser Plugin
Replies: 19
Views: 8990

Re: Ximagic Denoiser Plugin

I suppose you mean the .msi of the MP version of the Denoiser, it take more time because it install the multiprocessor libraries.
by brodriguez
Sun Dec 20, 2009 1:48 am
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

Good day, Blas. Merry Christmas to you. Merry Christmas to you also. :) I have another question regarding grayscales: Do you know how many levels (shades) of gray do produce error-diffusion methods (floyd-steinberg for instance)? When using grids, you already pointed the right formulas to me, but h...
by brodriguez
Mon Dec 14, 2009 12:43 pm
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

Doing a grayscale + error diffussion filter before, if the bitmap is a photographic image. The previous image was 16 colours already. If you apply several grayscale transformations, the results are very difficult to analyze. Resolution and gray levels of the resulting image can't be calculated with...
by brodriguez
Fri Nov 27, 2009 9:55 am
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

Hello. I test the image you post, comparing Ulichney 45 8x8 and Halftone 45 8x8. I get very similar results on screen, but I can't test it on a B/W printer. The only way to mitigate them is to reduce the number of final grays before. E.g. if you a are using a 45º 8x8 cell, reduce grays to 32 levels ...
by brodriguez
Mon Sep 21, 2009 10:50 pm
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

eL_PuSHeR wrote:By the way. What does have to do error-diffusion (Ulichney) with the 45º cell halftones?
Both, the Ulichney error diffusion dither and the Ulichney clustered-dot threshold matrices comes from a book authored by Robert Ulichney.

Ulichney, Robert; "Digital Halftoning"; The MIT Press; 1987.
by brodriguez
Mon Sep 21, 2009 4:54 pm
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

I think we talk about that previously. There are two variables which control the quality of the result, the lpi and the gray levels For 90º patterns (one point in each cell) lpi = dpi / cellsize levels = cellsize^2 For 45º patterns (two points in each cell) lpi = dpi / sqrt(2*((cellsize/2)^2))) leve...
by brodriguez
Thu Aug 13, 2009 4:32 pm
Forum: Miscellaneous
Topic: Ximagic Denoiser Plugin
Replies: 19
Views: 8990

Re: Ximagic Denoiser Plugin

The problem in this image is that it was printed with "artistic" patterns. For example see the torch. There are 3 band patterns. Those patterns are preserved by the more advanced denoise methods because those methods try to preserve everything but noise. To remove this patterns with denoise methods ...
by brodriguez
Wed Aug 12, 2009 11:59 pm
Forum: Miscellaneous
Topic: Ximagic Graydither
Replies: 30
Views: 10845

Re: Ximagic Graydither

Hello I didn't notice your posts until today. I have created some pseudo-diagonal screen halftones. Check them out. Skin tones appear weird but they can be cool for line-art. I test it and looks well. It seems you have discovered how to create screens. :D Hi, could you check this dithered test again...
by brodriguez
Sun Aug 02, 2009 11:39 pm
Forum: Miscellaneous
Topic: Ximagic Quantizer
Replies: 119
Views: 28526

Re: Ximagic Quantizer

Updated 2: Injected four filters again and deleted them in a row. No hangs so far (this is my computer at work). Could it be related to old-custom-filters leftovers in some way?. I will try at my home computer later again. Could be. The user thresholds are stored as subkeys of HKEY_CURRENT_USER//So...