Merge branch 'master' of https://github.com/Kirk-Fox/palette into pro…

…photo

palette/src/encoding/p3.rs

@@ -0,0 +1,314 @@
+//! The P3 color space(s) and standards.
+
+use core::marker::PhantomData;
+
+use crate::{
+    encoding::{FromLinear, IntoLinear, Srgb},
+    luma::LumaStandard,
+    num::{Powf, Real},
+    rgb::{Primaries, RgbSpace, RgbStandard},
+    white_point::{Any, WhitePoint, D65},
+    Mat3, Xyz, Yxy,
+};
+
+/// The theatrical DCI-P3 standard.
+///
+/// This standard uses a gamma 2.6 transfer function and a white point of ~6300K that
+/// matches the color of xenon bulbs used in theater projectors
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct DciP3;
+
+impl<T: Real> Primaries<T> for DciP3 {
+    fn red() -> Yxy<Any, T> {
+        Yxy::new(
+            T::from_f64(0.680),
+            T::from_f64(0.320),
+            T::from_f64(0.209492),
+        )
+    }
+    fn green() -> Yxy<Any, T> {
+        Yxy::new(
+            T::from_f64(0.265),
+            T::from_f64(0.690),
+            T::from_f64(0.721595),
+        )
+    }
+    fn blue() -> Yxy<Any, T> {
+        Yxy::new(
+            T::from_f64(0.150),
+            T::from_f64(0.060),
+            T::from_f64(0.068913),
+        )
+    }
+}
+
+impl<T: Real> WhitePoint<T> for DciP3 {
+    fn get_xyz() -> Xyz<Any, T> {
+        Xyz::new(
+            T::from_f64(0.314 / 0.351),
+            T::from_f64(1.0),
+            T::from_f64(0.335 / 0.351),
+        )
+    }
+}
+
+impl RgbSpace for DciP3 {
+    type Primaries = DciP3;
+    type WhitePoint = DciP3;
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn rgb_to_xyz_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+            0.4451698, 0.2771344, 0.1722827,
+            0.2094917, 0.7215953, 0.0689131,
+            0.0000000, 0.0470606, 0.9073554,
+        ])
+    }
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn xyz_to_rgb_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+             2.7253940, -1.0180030, -0.4401632,
+            -0.7951680,  1.6897321,  0.0226472,
+             0.0412419, -0.0876390,  1.1009294,
+        ])
+    }
+}
+
+impl RgbStandard for DciP3 {
+    type Space = DciP3;
+    type TransferFn = P3Gamma;
+}
+
+impl LumaStandard for DciP3 {
+    type WhitePoint = DciP3;
+    type TransferFn = P3Gamma;
+}
+
+/// The Canon DCI-P3+ color space and standard.
+///
+/// This standard has the same white point as [`DciP3`], but has a much wider gamut and
+/// no standardized transfer function (left to user preference). The generic `F` in
+/// this struct represents the chosen transfer function.
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct DciP3Plus<F>(PhantomData<F>);
+
+impl<T: Real, F> Primaries<T> for DciP3Plus<F> {
+    fn red() -> Yxy<Any, T> {
+        Yxy::new(T::from_f64(0.740), T::from_f64(0.270), T::from_f64(0.203986))
+    }
+    fn green() -> Yxy<Any, T> {
+        Yxy::new(T::from_f64(0.220), T::from_f64(0.780), T::from_f64(0.882591))
+    }
+    fn blue() -> Yxy<Any, T> {
+        Yxy::new(
+            T::from_f64(0.090),
+            T::from_f64(-0.090),
+            T::from_f64(-0.086577),
+        )
+    }
+}
+
+impl<F> RgbSpace for DciP3Plus<F> {
+    type Primaries = DciP3Plus<F>;
+    type WhitePoint = DciP3;
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn rgb_to_xyz_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+            0.5590736, 0.2489359,  0.0865774,
+            0.2039863, 0.8825911, -0.0865774,
+           -0.0075550, 0.0000000,  0.9619710,
+        ])
+    }
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn xyz_to_rgb_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+             1.9904035, -0.5613959, -0.2296619,
+            -0.4584928,  1.2623460,  0.1548755,
+             0.0156321, -0.0044090,  1.0377287,
+        ])
+    }
+}
+
+impl<F> RgbStandard for DciP3Plus<F> {
+    type Space = DciP3Plus<F>;
+    type TransferFn = F;
+}
+
+impl<F> LumaStandard for DciP3Plus<F> {
+    type WhitePoint = DciP3;
+    type TransferFn = F;
+}
+
+/// A gamma 2.6 transfer function used by some P3 variants
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct P3Gamma;
+
+impl<T> IntoLinear<T, T> for P3Gamma
+where
+    T: Real + Powf,
+{
+    #[inline]
+    fn into_linear(encoded: T) -> T {
+        encoded.powf(T::from_f64(2.6))
+    }
+}
+
+impl<T> FromLinear<T, T> for P3Gamma
+where
+    T: Real + Powf,
+{
+    #[inline]
+    fn from_linear(linear: T) -> T {
+        linear.powf(T::from_f64(1.0 / 2.6))
+    }
+}
+
+/// The Display P3 standard.
+///
+/// This standard uses the same primaries as [`DciP3`] but with a [`D65`] white point
+/// and the [`Srgb`] transfer function.
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct DisplayP3;
+
+impl<T: Real> Primaries<T> for DisplayP3 {
+    fn red() -> Yxy<Any, T> {
+        Yxy::new(T::from_f64(0.680), T::from_f64(0.320), T::from_f64(0.22900))
+    }
+    fn green() -> Yxy<Any, T> {
+        Yxy::new(T::from_f64(0.265), T::from_f64(0.690), T::from_f64(0.69173))
+    }
+    fn blue() -> Yxy<Any, T> {
+        Yxy::new(T::from_f64(0.150), T::from_f64(0.060), T::from_f64(0.07927))
+    }
+}
+impl RgbSpace for DisplayP3 {
+    type Primaries = DisplayP3;
+    type WhitePoint = D65;
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn rgb_to_xyz_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+            0.4866327, 0.2656632, 0.1981742,
+            0.2290036, 0.6917267, 0.0792697,
+            0.0000000, 0.0451126, 1.0437174,
+        ])
+    }
+
+    #[rustfmt::skip]
+    #[inline(always)]
+    fn xyz_to_rgb_matrix() -> Option<Mat3<f64>> {
+        // Matrix calculated using https://www.russellcottrell.com/photo/matrixCalculator.htm
+        Some([
+             2.4931808, -0.9312655, -0.4026597,
+            -0.8295031,  1.7626941,  0.0236251,
+             0.0358536, -0.0761890,  0.9570926,
+        ])
+    }
+}
+
+impl RgbStandard for DisplayP3 {
+    type Space = DisplayP3;
+    type TransferFn = Srgb;
+}
+
+impl LumaStandard for DisplayP3 {
+    type WhitePoint = D65;
+    type TransferFn = Srgb;
+}
+
+#[cfg(test)]
+mod test {
+    #[cfg(feature = "approx")]
+    mod conversion {
+        use crate::{
+            convert::IntoColorUnclamped,
+            encoding::p3::{DciP3, DciP3Plus, DisplayP3, P3Gamma},
+            matrix::{matrix_inverse, rgb_to_xyz_matrix},
+            rgb::{Primaries, RgbSpace},
+            white_point::{Any, WhitePoint, D65},
+            Xyz,
+        };
+
+        #[test]
+        fn rgb_to_xyz_display_p3() {
+            let dynamic = rgb_to_xyz_matrix::<DisplayP3, f64>();
+            let constant = DisplayP3::rgb_to_xyz_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn xyz_to_rgb_display_p3() {
+            let dynamic = matrix_inverse(rgb_to_xyz_matrix::<DisplayP3, f64>());
+            let constant = DisplayP3::xyz_to_rgb_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn rgb_to_xyz_dci_p3() {
+            let dynamic = rgb_to_xyz_matrix::<DciP3, f64>();
+            let constant = DciP3::rgb_to_xyz_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn xyz_to_rgb_dci_p3() {
+            let dynamic = matrix_inverse(rgb_to_xyz_matrix::<DciP3, f64>());
+            let constant = DciP3::xyz_to_rgb_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn rgb_to_xyz_dci_p3_plus() {
+            let dynamic = rgb_to_xyz_matrix::<DciP3Plus<P3Gamma>, f64>();
+            let constant = DciP3Plus::<P3Gamma>::rgb_to_xyz_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn xyz_to_rgb_dci_p3_plus() {
+            let dynamic = matrix_inverse(rgb_to_xyz_matrix::<DciP3Plus<P3Gamma>, f64>());
+            let constant = DciP3Plus::<P3Gamma>::xyz_to_rgb_matrix().unwrap();
+            assert_relative_eq!(dynamic[..], constant[..], epsilon = 0.0000001);
+        }
+
+        #[test]
+        fn primaries_display_p3() {
+            let red: Xyz<Any, f64> = DisplayP3::red().into_color_unclamped();
+            let green: Xyz<Any, f64> = DisplayP3::green().into_color_unclamped();
+            let blue: Xyz<Any, f64> = DisplayP3::blue().into_color_unclamped();
+            // Compare sum of primaries to white point.
+            assert_relative_eq!(red + green + blue, D65::get_xyz(), epsilon = 0.00001)
+        }
+
+        #[test]
+        fn primaries_dci_p3() {
+            let red: Xyz<Any, f64> = DciP3::red().into_color_unclamped();
+            let green: Xyz<Any, f64> = DciP3::green().into_color_unclamped();
+            let blue: Xyz<Any, f64> = DciP3::blue().into_color_unclamped();
+            // Compare sum of primaries to white point.
+            assert_relative_eq!(red + green + blue, DciP3::get_xyz(), epsilon = 0.00001)
+        }
+
+        #[test]
+        fn primaries_dci_p3_plus() {
+            let red: Xyz<Any, f64> = DciP3Plus::<P3Gamma>::red().into_color_unclamped();
+            let green: Xyz<Any, f64> = DciP3Plus::<P3Gamma>::green().into_color_unclamped();
+            let blue: Xyz<Any, f64> = DciP3Plus::<P3Gamma>::blue().into_color_unclamped();
+            // Compare sum of primaries to white point.
+            assert_relative_eq!(red + green + blue, DciP3::get_xyz(), epsilon = 0.00001)
+        }
+    }
+}