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Old 11-18-2013, 03:51 AM   #39
Jellby
frumious Bandersnatch
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Location: Spaniard in Sweden
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When direct resizing causes visible artifacts (aliasing or moiré patterns), it often helps if the resize is done in several steps. For instance a 50% resize is equivalent to three consecutive 80% resizes (plus one 97.66%, if you want to be exact): 0.5 = 0.8*0.8*0.8*0.9766

This is demonstrated, I hope, with the attached files

021_large, 238_large -> original size, cleaned, cropped, etc.
021_aliased, 238_moire -> direct 50% resize
021_better, 238_better -> multi-step resize, plus levels to remove some of the blurriness (use the burn layer trick again to see that).

I'll leave the color reductions and lossless PNG optimizations for others
Attached Files
File Type: zip samples.zip (4.88 MB, 173 views)
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