[css-color-hdr][editorial] Add examples of sRGB white in various colo…

…r spaces
w3c · Nov 20, 2024 · 08c2868 · 08c2868
1 parent 5585f16
commit 08c2868
Showing 1 changed file with 47 additions and 7 deletions.
diff --git a/css-color-hdr-1/Overview.bs b/css-color-hdr-1/Overview.bs
@@ -5,7 +5,7 @@ Shortname: css-color-hdr
 Level: 1
 Status: ED
 Group: csswg
-TR: https://www.w3.org/TR/css-color-hdr/
+TR: https://www.w3.org/TR/css-color-hdr-1/
 ED: https://drafts.csswg.org/css-color-hdr-1/
 Work Status: exploring
 Editor: Chris Lilley, W3C, https://svgees.us/, w3cid 1438
@@ -479,15 +479,16 @@ Predefined color spaces for HDR: {#predefined-HDR}
 		This color can be displayed for long periods,
 		or used for subtitles,
 		on any sized area of the screen.
-		Diffuse white is 203 cd/m².
+		It is the same color as sRGB ''white''.
+		Diffuse white is 203 cd/m²  [[!Rec_BT.2100]].
 		<pre>
 		<span class="swatch" style="--color: white"></span> color(rec2100-pq 0.58 0.58 0.58);
 		</pre>
 		This color represents a mid grey,
 		like a photographer's "18% reflectance grey" card,
 		at 17 cd/m².
 		<pre>
-		<span class="swatch" style="--color: rgb(46.632% 46.632% 46.632%)"></span> color(rec2100-pq 0.34 0.34 0.34);
+		<span class="swatch" style="--color: rgb(46.632% 46.632% 46.632%)"></span> color(rec2100-pq 0.34 0.34 0.34)
 		</pre>
 	</div>
 
@@ -595,7 +596,7 @@ Predefined color spaces for HDR: {#predefined-HDR}
 		This color represents a mid grey,
 		at 26 to 104  cd/m².
 		<pre>
-		<span class="swatch" style="--color: rgb(46.632% 46.632% 46.632%)"></span> color(rec2100-hlg 0.38 0.38 0.38);
+		<span class="swatch" style="--color: rgb(46.632% 46.632% 46.632%)"></span> color(rec2100-hlg 0.38 0.38 0.38)
 		</pre>
 	</div>
 
@@ -666,6 +667,19 @@ Predefined color spaces for HDR: {#predefined-HDR}
 		of 9.852 × 203 = 1,999 cd/m².
 	</div>
 
+
+	<div class="example">
+		This color represents a comfortable "diffuse white"
+		This color can be displayed for long periods,
+		or used for subtitles,
+		on any sized area of the screen.
+		It is the same color as sRGB ''white''.
+		Diffuse white is 203 cd/m²  [[!Rec_BT.2100]].
+		<pre>
+		<span class="swatch" style="--color: white"></span> color(rec2100-linear 1 1 1)
+		</pre>
+	</div>
+
 	A linear-light electro-optical transfer function is used.
 
 	It has the following characteristics:
@@ -734,6 +748,19 @@ Predefined color spaces for HDR: {#predefined-HDR}
 	(which also use a D65 whitepoint)
 	no chromatic adaptation step need be performed.
 
+	<div class="example">
+		This color represents a comfortable "diffuse white"
+		This color can be displayed for long periods,
+		or used for subtitles,
+		on any sized area of the screen.
+		It is the same color as sRGB ''white''.
+		Diffuse white is 203 cd/m²  [[!Rec_BT.2100]].
+		<pre>
+		<span class="swatch" style="--color: white"></span> color(jzazbz 0.22207 -0.00016 -0.00012)
+		</pre>
+	</div>
+	<!-- unclear why az and bz are not zero here. Is this the crosstalk term? -->
+
 <dfn export>JzCzHz</dfn> {#JzCzHz}
 -----------------
 
@@ -748,11 +775,11 @@ Predefined color spaces for HDR: {#predefined-HDR}
 	<div class="example">
 		This color represents the sRGB color "lime" in ''Jzazbz''
 		<pre>
-		<span class="swatch" style="--color: lime"></span> color(jzazbz 0.17542 -0.1179 0.1092);
+		<span class="swatch" style="--color: lime"></span> color(jzazbz 0.17542 -0.1179 0.1092)
 		</pre>
 		and here is the same color in the polar form
 		<pre>
-		<span class="swatch" style="--color: lime"></span> color(jzczhz 0.17542 0.1614 132.50);
+		<span class="swatch" style="--color: lime"></span> color(jzczhz 0.17542 0.1614 132.50)
 		</pre>
 	</div>
 
@@ -843,9 +870,22 @@ Converting JzCzHz colors to Jzazbz  colors</h4>
 	<div class="example">
 		This color represents the sRGB color "lime" in ''ICtCp''
 		<pre>
-		<span class="swatch" style="--color: lime"></span> color(ictcp 0.5393 -0.2643 -0.0625);
+		<span class="swatch" style="--color: lime"></span> color(ictcp 0.5393 -0.2643 -0.0625)
+		</pre>
+	</div>
+
+	<div class="example">
+		This color represents a comfortable "diffuse white"
+		This color can be displayed for long periods,
+		or used for subtitles,
+		on any sized area of the screen.
+		It is the same color as sRGB ''white''.
+		Diffuse white is 203 cd/m²  [[!Rec_BT.2100]].
+		<pre>
+		<span class="swatch" style="--color: white"></span> color(ictcp 0.58069 0 0)
 		</pre>
 	</div>
+
 
 Compositing SDR and HDR content {#Compositing-SDR-HDR}
 ===============================