From 0d098ddf6d9406ce7eca3d363b7119b4172b28d0 Mon Sep 17 00:00:00 2001 From: Carl Hetherington Date: Tue, 14 Apr 2015 23:24:54 +0100 Subject: Add a multiply by a Bradford matrix to rgb->xyz conversion. --- src/rgb_xyz.cc | 58 +++++++++++++++++++++++++++++++++++++++------------------- src/rgb_xyz.h | 3 ++- 2 files changed, 41 insertions(+), 20 deletions(-) diff --git a/src/rgb_xyz.cc b/src/rgb_xyz.cc index 40949f07..bd01b800 100644 --- a/src/rgb_xyz.cc +++ b/src/rgb_xyz.cc @@ -103,7 +103,10 @@ libdcp::xyz_to_rgb (shared_ptr xyz_frame, shared_ptr * i.e. AV_PIX_FMT_RGB48LE. */ shared_ptr -libdcp::rgb_to_xyz (shared_ptr rgb, shared_ptr lut_in, shared_ptr lut_out, double const colour_matrix[3][3]) +libdcp::rgb_to_xyz ( + shared_ptr rgb, shared_ptr lut_in, shared_ptr lut_out, + double const rgb_to_xyz[3][3], double const bradford[3][3] + ) { assert (lut_in->bit_depth() == 12); assert (lut_out->bit_depth() == 16); @@ -118,6 +121,10 @@ libdcp::rgb_to_xyz (shared_ptr rgb, shared_ptr lut_in, s double x, y, z; } d; + struct { + double x, y, z; + } e; + int jn = 0; for (int y = 0; y < rgb->size().height; ++y) { uint16_t* p = reinterpret_cast (rgb->data()[0] + y * rgb->stride()[0]); @@ -129,31 +136,44 @@ libdcp::rgb_to_xyz (shared_ptr rgb, shared_ptr lut_in, s s.b = lut_in->lut()[*p++ >> 4]; /* RGB to XYZ Matrix */ - d.x = ((s.r * colour_matrix[0][0]) + - (s.g * colour_matrix[0][1]) + - (s.b * colour_matrix[0][2])); + d.x = ((s.r * rgb_to_xyz[0][0]) + + (s.g * rgb_to_xyz[0][1]) + + (s.b * rgb_to_xyz[0][2])); - d.y = ((s.r * colour_matrix[1][0]) + - (s.g * colour_matrix[1][1]) + - (s.b * colour_matrix[1][2])); + d.y = ((s.r * rgb_to_xyz[1][0]) + + (s.g * rgb_to_xyz[1][1]) + + (s.b * rgb_to_xyz[1][2])); - d.z = ((s.r * colour_matrix[2][0]) + - (s.g * colour_matrix[2][1]) + - (s.b * colour_matrix[2][2])); + d.z = ((s.r * rgb_to_xyz[2][0]) + + (s.g * rgb_to_xyz[2][1]) + + (s.b * rgb_to_xyz[2][2])); + + /* Bradford matrix */ + e.x = ((d.x * bradford[0][0]) + + (d.y * bradford[0][1]) + + (d.z * bradford[0][2])); + + e.y = ((d.x * bradford[1][0]) + + (d.y * bradford[1][1]) + + (d.z * bradford[1][2])); + + e.z = ((d.x * bradford[2][0]) + + (d.y * bradford[2][1]) + + (d.z * bradford[2][2])); /* DCI companding */ - d.x = d.x * DCI_COEFFICIENT * 65535; - d.y = d.y * DCI_COEFFICIENT * 65535; - d.z = d.z * DCI_COEFFICIENT * 65535; + e.x = e.x * DCI_COEFFICIENT * 65535; + e.y = e.y * DCI_COEFFICIENT * 65535; + e.z = e.z * DCI_COEFFICIENT * 65535; - assert (d.x >= 0 && d.x < 65536); - assert (d.y >= 0 && d.y < 65536); - assert (d.z >= 0 && d.z < 65536); + assert (e.x >= 0 && e.x < 65536); + assert (e.y >= 0 && e.y < 65536); + assert (e.z >= 0 && e.z < 65536); /* Out gamma LUT */ - xyz->data(0)[jn] = lut_out->lut()[(int) d.x] * 4096; - xyz->data(1)[jn] = lut_out->lut()[(int) d.y] * 4096; - xyz->data(2)[jn] = lut_out->lut()[(int) d.z] * 4096; + xyz->data(0)[jn] = lut_out->lut()[(int) e.x] * 4096; + xyz->data(1)[jn] = lut_out->lut()[(int) e.y] * 4096; + xyz->data(2)[jn] = lut_out->lut()[(int) e.z] * 4096; ++jn; } diff --git a/src/rgb_xyz.h b/src/rgb_xyz.h index 734401dc..690ba08e 100644 --- a/src/rgb_xyz.h +++ b/src/rgb_xyz.h @@ -31,7 +31,8 @@ extern boost::shared_ptr xyz_to_rgb ( ); extern boost::shared_ptr rgb_to_xyz ( - boost::shared_ptr, boost::shared_ptr, boost::shared_ptr, double const colour_matrix[3][3] + boost::shared_ptr, boost::shared_ptr, boost::shared_ptr, + double const rgb_to_xyz[3][3], double const bradford[3][3] ); extern boost::shared_ptr xyz_to_xyz (boost::shared_ptr); -- cgit v1.2.3