[mediaqueries-4] Added dynamic-range

Author: Greg Whitworth

mediaqueries-4/Overview.bs

@@ -1695,22 +1695,51 @@ Color Display Quality: the 'color-gamut' feature</h3>
 	you can use this feature in a negated boolean-context fashion:
 	''not (color-gamut)''.
 
+<h3 id="dynamic-range">
+Dynamic Range: the 'dynamic-range' feature</h3>
+
+	<pre class='descdef mq'>
+	Name: dynamic-range
+	Value: standard | high
+	For: @media
+	Type: discrete
+	</pre>
+</h3>
+
+High dynamic range (HDR) represents the combination of brightness, color depth, transfer function, and color gamut.
+
+<dl dfn-type=value dfn-for="dynamic-range">
+	<dt><dfn>high</dfn>
+	<dd>
+		If the following are true for the UA and the output device:
+		* color gamut is <a>p3</a>, <a>rec2020</a>
+		* color depth is greater than 24 bit
+		* has a high contrast ratio
+	<dt><dfn>standard</dfn>
+	<dd>
+		If the following are true for the UA and the output device:
+		* color gamut is <a>sRGB</a>
+		* color depth is 24 bit or 8 bit per color component of RGB
+		* has a low contrast ratio
+</dl>
+
 <h3 id="video-prefixed-properties">
-Handling bi-plane displays</h3>
+Handling bi-plane scenarios</h3>
 
 	In some scenarios, such as TVs, they have a graphics plane dedicated 
 	to video that has its own discrete hardware. In order to allow UAs in 
 	environments that have more than one plane for graphics rendering the 
 	following properties should be used to correctly answer video specific 
 	queries.
 
-	For any useragent on a bi-plane device you **MUST** return the values for: 
-	<a>video-color-gamut</a>; <a>video-width</a>; <a>video-height</a>; <a>video-resolution</a>; 
-	based on the plane that renders video. If the useragent is not in a bi-plane scenario then 
-	you **MUST** return the values of the single plane (they're effectively aliases to their non-video counterparts).
+	For any UA on a bi-plane device you **MUST** return the values for: 
+	<a>video-color-gamut</a>; <a>video-width</a>; <a>video-height</a>; <a>video-resolution</a>;
+	<a>video-dynamic-range</a>; based on the plane that renders video. If the UA is not in a bi-plane 
+	scenario then it **MUST** return the values of the single plane 
+	(they're effectively aliases to their non-video counterparts).
 
 <h3 id="video-color-gamut">
-Color Display Quality: the 'video-color-gamut' feature</h3>
+Video Color Display Quality: the 'video-color-gamut' feature</h3>
 
 	<pre class='descdef mq'>
 	Name: video-color-gamut
@@ -1728,6 +1757,34 @@ The 'video-color-gamut' media feature describes the approximate range of colors
 
 Value and color space definitions are the same as <a href="#color-gamut">color-gamut</a>
 
+<h3 id="video-dynamic-range">
+Video Dynamic Range: the 'video-dynamic-range' feature</h3>
+
+	<pre class='descdef mq'>
+	Name: video-dynamic-range
+	Value: standard | high
+	For: @media
+	Type: discrete
+	</pre>
+</h3>
+
+High dynamic range (HDR) represents the combination of brightness, color depth, transfer function, and color gamut.
+
+<dl dfn-type=value dfn-for="video-dynamic-range">
+	<dt><dfn>high</dfn>
+	<dd>
+		If the following are true for the UA and the output device's video plane:
+		* color gamut is <a>p3</a>, <a>rec2020</a>
+		* color depth is greater than 24 bit
+		* has a high contrast ratio
+	<dt><dfn>standard</dfn>
+	<dd>
+		If the following are true for the UA and the output device's video plane:
+		* color gamut is <a>sRGB</a>
+		* color depth is 24 bit or 8 bit per color component of RGB
+		* has a low contrast ratio
+</dl>
+
 <h3 id="video-width">
 Video-Width: the '@media/video-width' feature</h3>
 
@@ -1765,7 +1822,7 @@ Video-Height: the '@media/video-height' feature</h3>
 
 	'@media/video-height' is <a>false in the negative range</a>.
 
-<h3 id="video-resolution" caniuse="css-media-video-resolution">
+<h3 id="video-resolution">
 Video Display Resolution: the 'video-resolution' feature</h3>
 
 	<pre class='descdef mq'>