[css-color-hdr] Add EOTF diagram

Author: svgeesus

css-color-hdr-1/Overview.bs

@@ -84,7 +84,7 @@ WPT Display: open
 			"rawDate": "2017-06-26"
 		},
 		"SMPTE-ST-2084": {
-			"href": "https://ieeexplore.ieee.org/document/7291452",
+			"href": "https://pub.smpte.org/latest/st2084/st2084-2014.pdf",
 			"title": "ST 2084:2014 - SMPTE Standard - High Dynamic Range Electro-Optical Transfer Function of Mastering Reference Displays",
 			"publisher": "SMPTE",
 			"rawDate": "2014-08-29",
@@ -105,6 +105,19 @@ Introduction {#intro}
 	This specification defines additions
 	to support High Dynamic Range (HDR).
 
+	<figure id="fig-eotf">
+		<p><img src="./images/lin-srgb-hlg-pq.png" alt=""></p>
+		<!-- alt text would be identical to figure caption -->
+		<figcaption>
+			The Electro-Optical Transfer Functions (EOTF)
+			of four color spaces: 
+			extended sRGB and linear-light sRGB
+			(as defined in CSS Color 4) and
+			the Perceptual Quantizer (PQ) and Hybrid Log-Gamma (HLG)
+			as defined in this specification, from [[Rec_BT.2100]].
+		</figcaption>
+	</figure>
+
 	While WCG specifications have been broadly stable for some decades,
 	HDR standards are less mature
 	and have undergone frequent revision in the last decade.