Hi @árpádp3188668
By one of those obscure whims that belong only to the Adobe dev team, the method app.colorTransform(…) expects and returns numbers in 0…1 — except for the LAB color space which still uses the original colorValue ranges (L: 0…100, a: -100..100, b: -100..100). So you need to properly downscale (then upscale) the values found in your Swatch/Color objects, as dictated by the specific color spaces under consideration.
Best is to have in your toolbox an adapter routine, like this:
function colorTransform(/*num[]*/vals,/*str|ColorSpace*/from,/*str|ColorSpace*/to,/*int=0*/dec, a,k,i)
//----------------------------------
// vals :: array of numbers *as processed by Color.colorValue*, that is
// - [0..255, 0..255, 0..255] in RGB space
// - [0..100, 0..100, 0..100, 0..100] in CMYK space
// - [0..100, -128..127, -128..127] in LAB space
// - [0..360, 0..100, 0..100] in HSB space
// (Rem: MixedInk is not supported by app.colorTransform.)
// from :: source ColorSpace or key string ('RGB'|'CMYK'|'HSB'|'LAB')
// to :: dest. ColorSpace or key string ('RGB'|'CMYK'|'HSB'|'LAB')
// dec :: rounding decimal digits (use -1 to bypass rounding);
// default is 0, i.e. rounding to the nearest integer.
// Returns the converted values as a new array of 3 or 4 numbers in
// the expected ranges (i.e. as processed by Color.colorValue).
// => num[]
{
from = from.toString().toUpperCase();
to = to.toString().toUpperCase();
if( from==to ) return vals.slice();
switch( from )
{
case 'RGB':
// app.colorTransform() expects r,g,b values in 0..1 (!)
// -> divide by 255
a = [ vals[0]/255, vals[1]/255, vals[2]/255 ];
break;
case 'CMYK':
// app.colorTransform() expects c,m,y,k values in 0..1 (!)
// -> divide by 100
a = [ .01*vals[0], .01*vals[1], .01*vals[2], .01*vals[3] ];
break;
case 'HSB':
// app.colorTransform() expects h,s,b values in 0..1 (!)
// -> divide h by 360 and s,b by 100
a = [ vals[0]/360, .01*vals[1], .01*vals[2] ];
break;
case 'LAB':
// app.colorTransform() expects L,a,b values as given in original range,
// that is, L:0..100, a:-100..100, b:-100..100
a = vals.slice();
break;
default:
throw "Unsupported color space " + from;
}
try
{
a = app.colorTransform(a, ColorSpace[from], ColorSpace[to]);
}
catch(e)
{
throw "Unable to convert " + a + " from " + from + " to " + to + " [" + e + "]";
}
switch( to )
{
case 'RGB':
// app.colorTransform() returns r,g,b values in 0..1 (!)
// -> multiply by 255
a[0]*=255; a[1]*=255; a[2]*=255;
break;
case 'CMYK':
// app.colorTransform() returns c,m,y,k values in 0..1 (!)
// -> multiply by 100
a[0]*=100; a[1]*=100; a[2]*=100; a[3]*=100;
break;
case 'HSB':
// app.colorTransform() returns h,s,b values in 0..1 (!)
// -> multiply h by 360 and s,b by 100
a[0]*=360; a[1]*=100; a[2]*=100;
break;
case 'LAB':
// app.colorTransform() returns L,a,b values in original range,
// that is, L:0..100, a:-100..100, b:-100..100
default:;
}
if( 0 <= (dec|=0) )
{
k = Math.pow(10,dec);
for(i=a.length ; i-- ; a[i]=Math.round(k*a[i])/k );
}
return a;
}
// TEST: Transform the CMYK color [41,46,56,36] to RGB
// ---
var res = colorTransform( [41,46,56,36], 'CMYK', 'RGB' );
alert( res ); // => 113,97,82
Best,
Marc
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