Turning imageData into alphaData (quickly)?
revlist at azurevision.co.uk
Mon Mar 13 05:46:25 EST 2006
Hi all, I've been lurking for a few years, but not posted for some
I'm doing quite a lot of stuff generating PNGs with transparency, and
wondered if there is any fast way to combine an 'image' img and a
A handler that goes through each RGB pixel and reduce it to a
grayscale value for use as alphaData was pretty easy, but for a
200x200px image that's 40,000 repeats, and takes minutes on a G5.
put the seconds into tStart
put "" into tMaskData
put the imageData of img "mask" into tImgData
put number of chars of tImgData / 4 & return into fld "status"
repeat with x = 1 to ((number of chars of tImgData) / 4)
if the mouse is down then exit to top
put charToNum(char (x*4)-2 of tImgData) into tR
put charToNum(char (x*4)-1 of tImgData) into tG
put charToNum(char (x*4) of tImgData) into tB
put the round of ((tR + tG + tB)/3) into tM
put numToChar(tM) after tMaskData
--put tM & return after fld "status"
put the seconds - tStart after fld "status"
As the project is currently on a Mac I can use AppleScripts to do it
all in Photoshop from two exported images (and makes it easy to add
drop-shadows), but for future cross-platform use this is a no-no.
Any ideas for a faster way? Cross-platform command-line tools?
Panoramic photography, from web to billboard, sunrise to moonrise
P.S. OS X 10.4.5, Rev 2.7 (haven't gone back and tried in 2.6 yet).
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