Add rgb_to_xyz with xyz buffer and stride.fastvideo

2 files changed, 79 insertions, 0 deletions

diff --git a/src/rgb_xyz.cc b/src/rgb_xyz.cc
index a8766b8e..2fb9cffd 100644
--- a/src/rgb_xyz.cc
+++ b/src/rgb_xyz.cc
@@ -327,3 +327,71 @@ dcp::rgb_to_xyz (
 
 	return xyz;
 }
+
+
+void
+dcp::rgb_to_xyz (
+	uint8_t const * rgb,
+	dcp::Size size,
+	int rgb_stride,
+	uint16_t* xyz,
+	int xyz_stride,
+	ColourConversion const & conversion,
+	optional<NoteHandler> note
+	)
+{
+	struct {
+		double r, g, b;
+	} s;
+
+	struct {
+		double x, y, z;
+	} d;
+
+	auto const * lut_in = conversion.in()->lut (12, false);
+	auto const * lut_out = conversion.out()->lut (16, true);
+
+	/* This is is the product of the RGB to XYZ matrix, the Bradford transform and the DCI companding */
+	double fast_matrix[9];
+	combined_rgb_to_xyz (conversion, fast_matrix);
+
+	int clamped = 0;
+	for (int y = 0; y < size.height; ++y) {
+		auto p = reinterpret_cast<uint16_t const *> (rgb + y * rgb_stride);
+		auto q = xyz + y * (xyz_stride / 2);
+		for (int x = 0; x < size.width; ++x) {
+
+			/* In gamma LUT (converting 16-bit to 12-bit) */
+			s.r = lut_in[*p++ >> 4];
+			s.g = lut_in[*p++ >> 4];
+			s.b = lut_in[*p++ >> 4];
+
+			/* RGB to XYZ, Bradford transform and DCI companding */
+			d.x = s.r * fast_matrix[0] + s.g * fast_matrix[1] + s.b * fast_matrix[2];
+			d.y = s.r * fast_matrix[3] + s.g * fast_matrix[4] + s.b * fast_matrix[5];
+			d.z = s.r * fast_matrix[6] + s.g * fast_matrix[7] + s.b * fast_matrix[8];
+
+			/* Clamp */
+
+			if (d.x < 0 || d.y < 0 || d.z < 0 || d.x > 65535 || d.y > 65535 || d.z > 65535) {
+				++clamped;
+			}
+
+			d.x = max (0.0, d.x);
+			d.y = max (0.0, d.y);
+			d.z = max (0.0, d.z);
+			d.x = min (65535.0, d.x);
+			d.y = min (65535.0, d.y);
+			d.z = min (65535.0, d.z);
+
+			/* Out gamma LUT */
+			*q++ = lrint (lut_out[lrint(d.x)] * 4095);
+			*q++ = lrint (lut_out[lrint(d.y)] * 4095);
+			*q++ = lrint (lut_out[lrint(d.z)] * 4095);
+		}
+	}
+
+	if (clamped && note) {
+		note.get()(NoteType::NOTE, String::compose("%1 XYZ value(s) clamped", clamped));
+	}
+}
diff --git a/src/rgb_xyz.h b/src/rgb_xyz.h
index 4a920efb..5f2da9a4 100644
--- a/src/rgb_xyz.h
+++ b/src/rgb_xyz.h
@@ -107,6 +107,17 @@ extern std::shared_ptr<OpenJPEGImage> rgb_to_xyz (
 	);
 
 
+extern void rgb_to_xyz (
+	uint8_t const * rgb,
+	dcp::Size size,
+	int rgb_stride,
+	uint16_t* xyz,
+	int xyz_stride,
+	ColourConversion const & conversion,
+	boost::optional<NoteHandler> note = boost::optional<NoteHandler> ()
+	);
+
+
 /** @param conversion Colour conversion.
  *  @param matrix Filled in with the product of the RGB to XYZ matrix, the Bradford transform and the DCI companding.
  */