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January 2002
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2002.01.25 14:27 "Re: How to interpret 16-bit GrayScale image?", by Thomas Kumlehn
Daniel McCoy <mccoy@pixar.com> schrieb: > ... > When converting the OTHER way, from 8 bits UP to 16 > bits, of course, you want to MULTIPLY by 257 and > not 256 so that you fill in the low bits. > That way FF becomes FFFF instead of FF00. > Clearly better. No question. I found a much faster way : Just copy the high byte down to the low byte 00 -> 00 00 01 -> 01 01 ... FE -> FE FE FF -> FF FF This way, the value range is evenly filled and it's much faster with bit ops (shift/or). But most often need colour corr. and the like and use LUTs anyway. ===== kind regards, Thomas Kumlehn PIXEL PARTNER (R) mobile +44 7960 384334