ImageMagickObject ... -fx "b*0.50"

[MvGulik]

trying to get ImageMagickObject Object.au3 to work with the following IM command '... -channel red -fx "b*0.50" ...'

$aCmd[1] = '-channel'

$aCmd[2] = 'red'

$aCmd[3] = '-fx'

$aCmd[4] = '"b*0.50"'

Func IM_Manual($This, Const $Image, Const $Dest, Const $aCmd) ;; cmd array input.

$This.IMObj.Convert($Image, $aCmd[0], $aCmd[1], $aCmd[2], $aCmd[3], $aCmd[4], $Dest)

EndFunc ;==>IM_AdaptiveResize

no matter what i do, the last '"a*0.50"' always result/evaluates to zero.

[willichan]

Maybe because you are limiting to the 'red' channel, but using blue for the 'fx'. I am not an ImageMagick expert, but that didn't look right to me.

[MvGulik]

IM code is fine. Works perfect when used directly with IM convert.exe. Passing the FX Parameter in the ImageMagickObject UDF is the problem I can't get around.

Edited March 15, 2011 by iEvKI3gv9Wrkd41u

[MvGulik]

~ Solved ~ Solved ~ Solved ~

well ... kinda

[jaberwacky]

b*0.50

What is b?

[MvGulik]

The Fx Expression Language

<snip>

channel functions:

channel(r,g,b,a), channel(c,m,y,k,a)

<snip>

oops, correction/addition.

symbols:

<snip>

r = red value (from RGBA), of a specific or current pixel

g = green ''

b = blue ''

a = alpha ''

o = opacity ''

<snip>

Edited March 23, 2011 by iEvKI3gv9Wrkd41u