jxl: Extending JXL CICP support to include P3 / color primaries 12 (#5054)

I tested out the JPEG XL CICP support and noticed that color primaries
12 was not supported. This pull request is looking to extend P3 support
for color primaries 12.
Note: color primaries 11 uses the DCI white point and color primaries 12
uses the D65 white point.

The JxlPrimaries enum only covers P3 primaries as value 11 and not 12.
See,

https://github.com/libjxl/libjxl/blob/main/lib/include/jxl/color_encoding.h#L55-L75
Further code is therefore required to account for this on read and
write.

Tests for read and write of color primaries 11 and 12 were added.

Signed-off-by: Shane Smith <shane.smith@dreamworks.com>

Author: shanesmith-dwa

src/jpegxl.imageio/jxlinput.cpp

@@ -383,9 +383,15 @@ JxlInput::open(const std::string& name, ImageSpec& newspec)
     if (have_color_encoding && color_encoding.primaries != JXL_PRIMARIES_CUSTOM
         && color_encoding.white_point != JXL_WHITE_POINT_CUSTOM
         && color_encoding.transfer_function != JXL_TRANSFER_FUNCTION_GAMMA) {
-        const int cicp[4] = { color_encoding.primaries,
-                              color_encoding.transfer_function, 0 /* RGB */,
-                              1 /* Full range */ };
+        int color_primaries = color_encoding.primaries;
+        // JxlPrimaries enum only covers P3 primaries as value 11 and not 12
+        // but CICP has separate code values based on white point.
+        if (color_primaries == JXL_PRIMARIES_P3
+            && color_encoding.white_point == JXL_WHITE_POINT_D65) {
+            color_primaries = 12;
+        }
+        const int cicp[4] = { color_primaries, color_encoding.transfer_function,
+                              0 /* RGB */, 1 /* Full range */ };
         m_spec.attribute("CICP", TypeDesc(TypeDesc::INT, 4), cicp);
         const ColorConfig& colorconfig(ColorConfig::default_colorconfig());
         string_view interop_id = colorconfig.get_color_interop_id(cicp);

src/jpegxl.imageio/jxloutput.cpp

@@ -571,7 +571,18 @@ JxlOutput::save_image(const void* data)
         // primaries and white point are not currently used but could help
         // support more CICP codes.
         JxlColorEncoding color_encoding {};
-        color_encoding.primaries         = JxlPrimaries(cicp[0]);
+        color_encoding.primaries = JxlPrimaries(cicp[0]);
+        // CICP primaries 11 and 12 both represent P3, but with different white points.
+        if (cicp[0] == 11) {
+            color_encoding.white_point = JXL_WHITE_POINT_DCI;
+        }
+        // JxlPrimaries enum only covers P3 primaries as value 11 and not 12.
+        else if (cicp[0] == 12) {
+            color_encoding.primaries   = JXL_PRIMARIES_P3;
+            color_encoding.white_point = JXL_WHITE_POINT_D65;
+        } else {
+            color_encoding.white_point = JXL_WHITE_POINT_D65;
+        }
         color_encoding.transfer_function = JxlTransferFunction(cicp[1]);
         color_encoding.color_space       = JXL_COLOR_SPACE_RGB;
 
@@ -581,10 +592,7 @@ JxlOutput::save_image(const void* data)
         switch (color_encoding.primaries) {
         case JXL_PRIMARIES_SRGB:
         case JXL_PRIMARIES_2100:
-        case JXL_PRIMARIES_P3:
-            supported_primaries        = true;
-            color_encoding.white_point = JXL_WHITE_POINT_D65;
-            break;
+        case JXL_PRIMARIES_P3: supported_primaries = true; break;
         case JXL_PRIMARIES_CUSTOM:  // Not an actual CICP code in JXL
             break;
         }

testsuite/jxl/ref/out.txt

@@ -42,3 +42,48 @@ tahoe-cicp-pq.jxl    :  128 x   96, 3 channel, uint8 jpegxl
     ICCProfile:profile_version: "4.4.0"
     ICCProfile:rendering_intent: "Perceptual"
     oiio:ColorSpace: "pq_rec2020_display"
+Reading tahoe-cicp-dcip3.jxl
+tahoe-cicp-dcip3.jxl :  128 x   96, 3 channel, uint8 jpegxl
+    SHA-1: 069F1A3E5567349C2D34E535B29913029EF1B09C
+    channel list: R, G, B
+    CICP: 11, 17, 0, 1
+    ICCProfile: 0, 0, 2, 24, 106, 120, 108, 32, 4, 64, 0, 0, 109, 110, 116, 114, ... [536 x uint8]
+    ICCProfile:attributes: "Reflective, Glossy, Positive, Color"
+    ICCProfile:cmm_type: 1786276896
+    ICCProfile:color_space: "RGB"
+    ICCProfile:copyright: "CC0"
+    ICCProfile:creation_date: "2019:12:01 00:00:00"
+    ICCProfile:creator_signature: "6a786c20"
+    ICCProfile:device_class: "Display device profile"
+    ICCProfile:flags: "Not Embedded, Independent"
+    ICCProfile:manufacturer: "0"
+    ICCProfile:model: "0"
+    ICCProfile:platform_signature: "Apple Computer, Inc."
+    ICCProfile:profile_connection_space: "XYZ"
+    ICCProfile:profile_description: "RGB_DCI_DCI_Per_DCI"
+    ICCProfile:profile_size: 536
+    ICCProfile:profile_version: "4.4.0"
+    ICCProfile:rendering_intent: "Perceptual"
+Reading tahoe-cicp-displayp3.jxl
+tahoe-cicp-displayp3.jxl :  128 x   96, 3 channel, uint8 jpegxl
+    SHA-1: 069F1A3E5567349C2D34E535B29913029EF1B09C
+    channel list: R, G, B
+    CICP: 12, 13, 0, 1
+    ICCProfile: 0, 0, 2, 4, 106, 120, 108, 32, 4, 64, 0, 0, 109, 110, 116, 114, ... [516 x uint8]
+    ICCProfile:attributes: "Reflective, Glossy, Positive, Color"
+    ICCProfile:cmm_type: 1786276896
+    ICCProfile:color_space: "RGB"
+    ICCProfile:copyright: "CC0"
+    ICCProfile:creation_date: "2019:12:01 00:00:00"
+    ICCProfile:creator_signature: "6a786c20"
+    ICCProfile:device_class: "Display device profile"
+    ICCProfile:flags: "Not Embedded, Independent"
+    ICCProfile:manufacturer: "0"
+    ICCProfile:model: "0"
+    ICCProfile:platform_signature: "Apple Computer, Inc."
+    ICCProfile:profile_connection_space: "XYZ"
+    ICCProfile:profile_description: "DisplayP3"
+    ICCProfile:profile_size: 516
+    ICCProfile:profile_version: "4.4.0"
+    ICCProfile:rendering_intent: "Perceptual"
+    oiio:ColorSpace: "srgb_p3d65_scene"

testsuite/jxl/run.py

@@ -13,6 +13,12 @@
 command += oiiotool ("../common/tahoe-tiny.tif --cicp \"9,16,9,1\" -o tahoe-cicp-pq.jxl")
 command += info_command ("tahoe-cicp-pq.jxl", safematch=True)
 
+command += oiiotool ("../common/tahoe-tiny.tif --cicp \"11,17,0,1\" -o tahoe-cicp-dcip3.jxl")
+command += info_command ("tahoe-cicp-dcip3.jxl", safematch=True)
+
+command += oiiotool ("../common/tahoe-tiny.tif --cicp \"12,13,0,1\" -o tahoe-cicp-displayp3.jxl")
+command += info_command ("tahoe-cicp-displayp3.jxl", safematch=True)
+
 outputs = [
             "test-jxl.icc",
             "out.txt"