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local p = Pixel() local histoR = {} local histoG = {} local histoB = {} local histoA = {}
local r,g,b,a
-- initialise the histogram table for i = 0,255 do
histoR[i] = 0
histoG[i] = 0
histoB[i] = 0
histoA[i] = 0
end
for y=0,Height-1 do
if self.Status ~= "OK" then break end
for x=0,Width-1 do
img:GetPixel(x,y, p)
-- convert float 0..1 values into int 0.255 r = math.floor(p.R * 255)
g = math.floor(p.G * 255) b = math.floor(p.B * 255)
a = math.floor(p.A * 255)
-- check for out-of-range colors
if r >= 0 and r <= 255 then histoR[r] = histoR[r] + 1 end
A simple 8 bit histogram function
if | g | >= | 0 | and | g | <= | 255 | then | histoG[g] | = | histoG[g] | + | 1 | end | ||
if | b | >= | 0 | and | b | <= | 255 | then | histoB[b] | = | histoB[b] | + | 1 | end | ||
if | a | >= | 0 | and | a | <= | 255 | then | histoA[a] | = | histoA[a] | + | 1 | end | ||
end | ||||||||||||||||
end | ||||||||||||||||