hunter lab

1 files changed, 29 insertions, 2 deletions

diff --git a/js/color.js b/js/color.js
index 9c2ab09..a8479b9 100644
--- a/js/color.js
+++ b/js/color.js
@@ -49,12 +49,39 @@ function xyz2rgb(xyz){
   return [r,g,b]
 }
 
+function xyz2hunterlab (X,Y,Z) {
+  if (X.length) {
+    Z = X[2]
+    Y = X[1]
+    X = X[0]
+  }
+  var L = 10 * sqrt( Y )
+  var a = 17.5 * ( ( ( 1.02 * X ) - Y ) / sqrt( Y ) )
+  var b = 7 * ( ( Y - ( 0.847 * Z ) ) / sqrt( Y ) )
+  return [L,a,b]
+}
+
+function hunterlab2xyz (L,a,b) {
+  if (L.length) {
+    b = L[2]
+    a = L[1]
+    L = L[0]
+  }
+  var_Y = L / 10
+  var_X = a / 17.5 * L / 10
+  var_Z = b / 7 * L / 10
+
+  Y = Math.pow(var_Y, 2)
+  X = ( var_X + Y ) / 1.02
+  Z = -( var_Z - Y ) / 0.847
+  return [X,Y,Z]
+}
 // Daylight Illuminant (D65)
 var REF_X = 95.047
 var REF_Y = 100.000
 var REF_Z = 108.883
 
-function xyz2lab (xyz) {
+function xyz2cielab (xyz) {
   var var_X = xyz[0] / ref_X          //ref_X =  95.047   Observer= 2°, Illuminant= D65
   var var_Y = xyz[1] / ref_Y          //ref_Y = 100.000
   var var_Z = xyz[2] / ref_Z          //ref_Z = 108.883
@@ -73,7 +100,7 @@ function xyz2lab (xyz) {
   return [L,a,b]
 }
 
-function lab2xyz (lab){
+function cielab2xyz (lab){
   var var_Y = ( lab[0] + 16 ) / 116
   var var_X = lab[1] / 500 + var_Y
   var var_Z = var_Y - lab[2] / 200