[Q:] S simple q wrt scaling
Hi there, the following appears to me to be a rather silly question. However I'm new to the gimp, and new to the list, but I've looked through the archive, and I've RTFM without success. I'm trying to rescale an image (say from 1000 pixel to 100 pixel to use a logo on the web). That works ok. However the sclaing process does only simple resampling of the imga, which results in a rather jagged look on the scaled image. There muts be away to get a smooth scaling (say by bilinear filtering), but I can't see it (maybe it is too obvious?) Thanks for any enlightment Uli -- Uli Wortmann Dept. of Geology Fax (Switzerland) (1) 632 1030 ETH-ZuerichFon3694 Visit the SPOC-team at http://www.spoc.ethz.ch
Low Quality Gifs
Hi I have been trying to create gifs with transparent backgrounds for use on my website. No real problems (RTFM'd) with that, but the quality is appalling in both colour and resolution. As an example http://www.stutchbury.com/images/projects.gif versus a similar image in PNG format at http://www.stutchbury.com/images/projects_d.png . It is on the conversion to 'indexed' that the degradation occurs. Any ideas? Regards Philip -- Philip Fletcher Stutchbury Ltd [EMAIL PROTECTED] +44(0)7860 40
RE: Low Quality Gifs
The palette you've used to make your gif image is not good. To correct this, open your png file, choose "Image/Mode/Indexed" and then choose generate optimal palette. Then save it under gif format. I've a question too: ie4 seem not support png format. In fact, when i've clicked on you png link below, ie4 has asked to me if i want to "save or open the file", and hasn't displayed it. Why ? -Message d'origine- De: Philip Fletcher [mailto:[EMAIL PROTECTED]] Date: vendredi 06 octobre 2000 13:34 À: gimp-user Objet: Low Quality Gifs Hi I have been trying to create gifs with transparent backgrounds for use on my website. No real problems (RTFM'd) with that, but the quality is appalling in both colour and resolution. As an example http://www.stutchbury.com/images/projects.gif versus a similar image in PNG format at http://www.stutchbury.com/images/projects_d.png . It is on the conversion to 'indexed' that the degradation occurs. Any ideas? Regards Philip -- Philip Fletcher Stutchbury Ltd [EMAIL PROTECTED] +44(0)7860 40
Re: [Q:] S simple q wrt scaling
Make sure your image is in RGB format before scaling it. If you are doing the scaling with an indexed image, antialiasing can't happen. You can also scecify cubic interpolation in your gimp preferences.
RE: Low Quality Gifs
Are you converting to indexed before or after merging all layers? The less colors you give it the better job it can do, so flatten out the colors from non-visable layers.
Re: Low Quality Gifs
hi, As an example http://www.stutchbury.com/images/projects.gif versus a similar image in PNG format at http://www.stutchbury.com/images/projects_d.png . It is on the conversion to 'indexed' that the degradation occurs. Any ideas? sure that your PNG image is also being shrunk down to 8-bit? GIF cannot have multi-transparency mapping. only one alpha level - whereas PNG can have nice blended transparency. in basic, PNG is a better image format alan
RE: Low Quality Gifs
hi, I've a question too: ie4 seem not support png format. In fact, when i've clicked on you png link below, ie4 has asked to me if i want to "save or open the file", and hasn't displayed it. Why ? because, as you said, IE4 doesnt support PNG. there are updates around, but its better to move to IE 5.x if you have to use that sort of thing ;-) ...now, gotta get 1.1.27 working! ;-) alan
RE: Little off-topic: PNG in browsers - Was: Low Quality Gifs
actually, it's about the same thing in IE4. If png image is embedded in a html page, it's displayed. But, if you request png file only, it display dialog "save or open". I don't think that IE support multitransparency in png files. -Message d'origine- De: Martin Edlman [mailto:[EMAIL PROTECTED]] Date: vendredi 06 octobre 2000 14:03 À: COUTIER Eric Objet: Little off-topic: PNG in browsers - Was: Low Quality Gifs COUTIER Eric wrote: The palette you've used to make your gif image is not good. To correct this, open your png file, choose "Image/Mode/Indexed" and then choose generate optimal palette. Then save it under gif format. I've a question too: ie4 seem not support png format. In fact, when i've clicked on you png link below, ie4 has asked to me if i want to "save or open the file", and hasn't displayed it. Why ? I think EI4.0 doesn't support PNG yet, upgrade to IE5.x. On the other hand I have problem with Netscape under Linux (I didn't test it under Windoze) - it doesn't support transparency in PNG, and it does display PNG when it's embedded into a HTML page but when NN is requested to display PNG image alone (e.g. using View Image) is complains "Unsupported image type". Stupid thing, does anybody know if there is some fix tothis problem. I have NN 4.75/Linux i386. -- Martin Edlman Fortech s.r.o, Litomysl Public PGP key: http://edas.visaci.cz/#pgpkeys
Links for PNG support in Browser
After the discussion about PNG/GIF, i've found this information about PNG support in browser on libpng.org: http://www.libpng.org/pub/png/pngapbr.html (current status of PNG support level in browser) http://www.libpng.org/pub/png/pngs-img.html (samples to test your browser capabilities in displaying PNG images) Salutations. Eric COUTIER Direction Qualité Groupe Faurecia Beaulieu Tel/Fax: 03.81.37.51.39 | 03.81.37.50.70
Newbie question: Banners
Here's what I think should be a quicky ... (I have no graphic design experience, and have used the GIMP mostly just for format covnersions). I want to make a banner, say 640 pixels wide by 64 pixels high. I have a 64x64 pixel image that I want copied into that banner 10 times. Is there a simple way of doing this besides cutpaste?
Re: [Q:] S simple q wrt scaling
"Ulrich G. Wortmann" wrote: I'm trying to rescale an image (say from 1000 pixel to 100 pixel to use a logo on the web). That works ok. However the sclaing process does only simple resampling of the imga, which results in a rather jagged look on the scaled image. There muts be away to get a smooth scaling (say by bilinear filtering), but I can't see it (maybe it is too obvious?) If you're scaling an image down by more than a small amount, blur it first. Use a gaussian filter - I'd start with a radius of half the scale factor and adjust until the result looks good. -- David Hodson -- [EMAIL PROTECTED] -- this night wounds time
Re: Low Quality Gifs
Do all of the work on your image in the RGB format that the Gimp will start you out with. If you are in a situation where you must save your image often, saving in the Gimps native format "xcf" saves the most information and is the least hassle. The very last step before the "Save" should be the conversion from RGB to indexed. The Gimp makes lovely gifs. What is ie? COUTIER Eric wrote: The palette you've used to make your gif image is not good. To correct this, open your png file, choose "Image/Mode/Indexed" and then choose generate optimal palette. Then save it under gif format.
