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We want to pinpoint some locations on a map with some external GIF symbolizers. The issue we have is visible in the attached image*: looks like somethings happens on a sub-pixel level, so that the resulting pluses look mutated :), most of them are somehow distorted/blurred/interpolated. The original external GIF is shown in the right lower corner of the image* (simple and sharp 5x5 pixel "+" symbol).

Thank you in advance for any clue or solution.



Original image:

enter image description here

Magnified image:

enter image description here

Update: Same thing happens with well known symbolizers (e.g. MARK_CROSS):

final Mark mark = sb.createMark(StyleBuilder.MARK_CROSS,, Color.yellow, 1);
final Graphic graphics = sb.createGraphic(null, mark, null, 1, 10, 0);
final Style style2 = sb.createStyle(sb.createPointSymbolizer(graphics));

enter image description here

share|improve this question
might need a bigger image to see what's going on – iant Sep 19 '12 at 14:04
I uploaded the same image with 4x magnification. I hope this helps. – skipr Sep 19 '12 at 21:17
Anyone? Anything? A wild guess? – skipr Sep 27 '12 at 6:54
Looks like an aliasing problem - what does it look like with a wellknownsynbol instead? – iant Sep 27 '12 at 7:54
Is the map being rendered to JPEG after the markers are added? If so, can it be rendered to GIF or PNG instead? That will avoid aliasing issues caused when JPEG compression is applied to discrete graphics. – user3461 Sep 27 '12 at 12:46

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