[css-color-hdr] Added informative ref to Perrin ICtCp paper

Author: svgeesus

css-color-hdr-1/Overview.bs

@@ -46,6 +46,18 @@ WPT Display: open
 			"publisher": "VESA",
 			"rawDate": "2024-05-17"
 		},
+		"Perrin et al": {
+			"authors": [
+				"Perrin, A-F.",
+				"Rerabek, M.",
+				"Husak, W.",
+				"Ebrahimi, T."
+				],
+			"href": "https://ieeexplore.ieee.org/document/8333011",
+			"title": "ICtCp Versus Y'CbCr: Evaluation of ICtCp Color Space and an Adaptive Reshaper for HDR and WCG",
+			"publisher": "IEEE Consumer Electronics Magazine",
+			"rawDate": "2018-05"
+		},
 		"Rec_BT.814": {
 			"title": "Specifications of PLUGE test signals and alignment procedures for setting of brightness and contrast of displays",
 			"href": "https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.814-4-201807-I!!PDF-E.pdf",
@@ -874,7 +886,7 @@ Converting JzCzHz colors to Jzazbz  colors</h4>
 <dfn export>ICtCp</dfn> {#ICtCp}
 -----------------
 
-	The ''ICtCp'' color space
+	The ''ICtCp'' color space [[?Perrin et al]]
 	is defined as Constant Intensity IC<sub>T</sub>C<sub>P</sub> signal format
 	in [[!Rec_BT.2100]] and accepts three numeric parameters,
 	with I representing the Intensity
@@ -1058,6 +1070,28 @@ Serializing values of the ''color()'' function</h3>
 	This code also assumes all of the conversion code from
 	[[css-color-4#color-conversion-code]] is available.
 
+<h3 id="ictcp_code">
+	Sample code for ''ICtCp''
+</h3>
+
+Rather than first requiring conversion to 
+''rec2100-linear'', as defined in [[!Rec_BT.2100]],
+this sample code proceeds directly from absolute CIE XYZ
+for compatibility with the other color conversion code.
+
+The 4% crosstalk matrix is also built into the XYZ to LMS step,
+rather than being applied separately.
+
+The end result is identical, this just takes fewer steps.
+
+<pre class="include-code lang-javascript">
+	path: ICtCp.js
+	highlight: js
+</pre>
+
+
+
+
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