My take on this would be these are just resampling artifacts. Different sampling algorithms (of which Irfanview provides quite a few) may well give different results.
If you've got a simple graphic like you describe, I would suggest decreasing the colour depth to e.g. 16 colours prior to resizing/resampling, and then you shouldn't find you get subtle differences in e.g. blue. Other than that, the resampling results you describe are exactly what I would expect from a photographic image-manipulating program like Irfanview (I would content that Irfanview is for manipulating images, not necessarily graphics - they're different beasts). I wouldn't expect Sharpening to solve the problem. When one talks about sharpening an image it's probably exactly what you in particular don't want - sharpening makes the dark side of an edge subtley darker, and the light side lighter; that's what sharpening means in image-manipulating terms. In summary I would disagree that this is in any way a "problem" with Irfanview and it's ilk, but more a matter of expectations. Hope this helps, C. -----Original Message----- From: delphi-boun...@delphi.org.nz [mailto:delphi-boun...@delphi.org.nz] On Behalf Of John Bird The only problem I have struck with Irfanview (and other programs) is in resizing images: If I have an image I want to use, I will usually resize it to several different sizes, some small enough to be used as images on a TBitButton. If for example the image is Blue, and has a transparent (eg white) background and is resized smaller, there are a few pixels on and around the edge of the blue image on the background that get to be averaged to a light blue - in between white and blue. This is not a problem until the image is shown on a darker background, and the light blue pixels show as a small ragged bright edge to the image because they are not the transparent colour any more. I have experimented with the IrfanView option "Sharpen after resize" but this does not quite solve the problem - it seems to sharpen the edge of bright pixels, and sometimes introduces other oddities. Anyone else have a way to deal with this? I have often blown up the resized image using Photofiltre (ie view at 800%) and carefully brush the offending edge pixels back to the transparent colour. Very fiddly! John -------------------------------------------------- From: "Conor Boyd" <conor.b...@trimble.co.nz> > Yeah, Irfanview would be my tool of choice for this sort of task (and > many others). > > www.irfanview.com > > Cheers, > > C. > > -----Original Message----- > From: delphi-boun...@delphi.org.nz > [mailto:delphi-boun...@delphi.org.nz] > On Behalf Of John Bird > > I think it disappeared in later Delphi, > > I use any of IrfanView, PhotoFiltre, Paint.Net - all freeware - > Irfanview > is a converter and viewer, the other two are excellent image editors > and convert too. > > What do others use? _______________________________________________ NZ Borland Developers Group - Delphi mailing list Post: delphi@delphi.org.nz Admin: http://delphi.org.nz/mailman/listinfo/delphi Unsubscribe: send an email to delphi-requ...@delphi.org.nz with Subject: unsubscribe
