sij/mapnik
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Merge pull request #3862 from mapnik/apply_color_blind_filter-fix

Browse source 
Fix apply_color_blind_filter to use correct color-space and avoid NAN…
This commit is contained in:
Artem Pavlenko 2018-02-20 16:48:31 +01:00 committed by GitHub
commit ff56c86446
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 41 additions and 60 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

92
include/mapnik/image_filter.hpp
View file

@ -28,7 +28,6 @@
#include <mapnik/image_filter_types.hpp> #include <mapnik/image_filter_types.hpp>
#include <mapnik/image_util.hpp> #include <mapnik/image_util.hpp>
#include <mapnik/util/hsl.hpp> #include <mapnik/util/hsl.hpp>
#pragma GCC diagnostic push #pragma GCC diagnostic push
#include <mapnik/warning_ignore.hpp> #include <mapnik/warning_ignore.hpp>
#include <boost/gil/gil_all.hpp> #include <boost/gil/gil_all.hpp>
@ -687,36 +686,37 @@ void apply_color_blind_filter(Src & src, ColorBlindFilter const& op)
rgba8_view_t src_view = rgba8_view(src); rgba8_view_t src_view = rgba8_view(src);
bool premultiplied = src.get_premultiplied(); bool premultiplied = src.get_premultiplied();
static constexpr double gamma = 2.2;
static constexpr double inv_gamma = 1.0/gamma;
for (std::ptrdiff_t y = 0; y < src_view.height(); ++y) for (std::ptrdiff_t y = 0; y < src_view.height(); ++y)
{ {
rgba8_view_t::x_iterator src_it = src_view.row_begin(static_cast<long>(y)); rgba8_view_t::x_iterator src_it = src_view.row_begin(static_cast<long>(y));
for (std::ptrdiff_t x = 0; x < src_view.width(); ++x) for (std::ptrdiff_t x = 0; x < src_view.width(); ++x)
{ {
// formula taken from boost/gil/color_convert.hpp:rgb_to_luminance
uint8_t & r = get_color(src_it[x], red_t()); uint8_t & r = get_color(src_it[x], red_t());
uint8_t & g = get_color(src_it[x], green_t()); uint8_t & g = get_color(src_it[x], green_t());
uint8_t & b = get_color(src_it[x], blue_t()); uint8_t & b = get_color(src_it[x], blue_t());
uint8_t & a = get_color(src_it[x], alpha_t()); uint8_t & a = get_color(src_it[x], alpha_t());
double dr = static_cast<double>(r)/255.0;
double dg = static_cast<double>(g)/255.0;
double db = static_cast<double>(b)/255.0;
double da = static_cast<double>(a)/255.0;
// demultiply // demultiply
if (da <= 0.0) if (a == 0)
{ {
r = g = b = 0; r = g = b = 0;
continue; continue;
} }
else if (premultiplied) else if (premultiplied)
{ {
dr /= da; std::uint32_t cr = (r * 255) / a;
dg /= da; std::uint32_t cg = (g * 255) / a;
db /= da; std::uint32_t cb = (b * 255) / a;
r = static_cast<uint8_t>((cr > 255) ? 255 : cr);
g = static_cast<uint8_t>((cg > 255) ? 255 : cg);
b = static_cast<uint8_t>((cb > 255) ? 255 : cb);
} }
// Convert source color into XYZ color space // Convert source color into XYZ color space
double pow_r = std::pow(dr, 2.2); double pow_r = std::pow(r, gamma);
double pow_g = std::pow(dg, 2.2); double pow_g = std::pow(g, gamma);
double pow_b = std::pow(db, 2.2); double pow_b = std::pow(b, gamma);
double X = (0.412424 * pow_r) + (0.357579 * pow_g) + (0.180464 * pow_b); double X = (0.412424 * pow_r) + (0.357579 * pow_g) + (0.180464 * pow_b);
double Y = (0.212656 * pow_r) + (0.715158 * pow_g) + (0.0721856 * pow_b); double Y = (0.212656 * pow_r) + (0.715158 * pow_g) + (0.0721856 * pow_b);
double Z = (0.0193324 * pow_r) + (0.119193 * pow_g) + (0.950444 * pow_b); double Z = (0.0193324 * pow_r) + (0.119193 * pow_g) + (0.950444 * pow_b);
@ -733,10 +733,6 @@ void apply_color_blind_filter(Src & src, ColorBlindFilter const& op)
if (std::abs(m_div2) < (std::numeric_limits<double>::epsilon())) continue; if (std::abs(m_div2) < (std::numeric_limits<double>::epsilon())) continue;
double deviate_x = (op.yint - yint) / (m - op.m); double deviate_x = (op.yint - yint) / (m - op.m);
double deviate_y = (m * deviate_x) + yint; double deviate_y = (m * deviate_x) + yint;
if (std::abs(deviate_y) < (std::numeric_limits<double>::epsilon()))
{
deviate_y = std::numeric_limits<double>::epsilon() * 2.0;
}
// Compute the simulated color's XYZ coords // Compute the simulated color's XYZ coords
X = deviate_x * Y / deviate_y; X = deviate_x * Y / deviate_y;
Z = (1.0 - (deviate_x + deviate_y)) * Y / deviate_y; Z = (1.0 - (deviate_x + deviate_y)) * Y / deviate_y;
@ -746,25 +742,14 @@ void apply_color_blind_filter(Src & src, ColorBlindFilter const& op)
// Difference between simulated color and neutral grey // Difference between simulated color and neutral grey
double diff_X = neutral_X - X; double diff_X = neutral_X - X;
double diff_Z = neutral_Z - Z; double diff_Z = neutral_Z - Z;
double diff_r = diff_X * 3.24071 + diff_Z * -0.498571; // XYZ->RGB (sRGB:D65) // XYZ->RGB (sRGB:D65)
double diff_g = diff_X * -0.969258 + diff_Z * 0.0415557; double diff_r = diff_X * 3.2407100 + diff_Z *-0.4985710;
double diff_b = diff_X * 0.0556352 + diff_Z * 1.05707; double diff_g = diff_X *-0.9692580 + diff_Z * 0.0415557;
if (std::abs(diff_r) < (std::numeric_limits<double>::epsilon())) double diff_b = diff_X * 0.0556352 + diff_Z * 1.0570700;
{ // XYZ->RGB (sRGB:D65)
diff_r = std::numeric_limits<double>::epsilon() * 2.0; double dr = X * 3.2407100 + Y *-1.537260 + Z *-0.4985710;
} double dg = X *-0.9692580 + Y * 1.875990 + Z * 0.0415557;
if (std::abs(diff_g) < (std::numeric_limits<double>::epsilon())) double db = X * 0.0556352 + Y *-0.203996 + Z * 1.0570700;
{
diff_g = std::numeric_limits<double>::epsilon() * 2.0;
}
if (std::abs(diff_b) < (std::numeric_limits<double>::epsilon()))
{
diff_b = std::numeric_limits<double>::epsilon() * 2.0;
}
// Convert to RGB color space
dr = X * 3.24071 + Y * -1.53726 + Z * -0.498571; // XYZ->RGB (sRGB:D65)
dg = X * -0.969258 + Y * 1.87599 + Z * 0.0415557;
db = X * 0.0556352 + Y * -0.203996 + Z * 1.05707;
// Compensate simulated color towards a neutral fit in RGB space // Compensate simulated color towards a neutral fit in RGB space
double fit_r = ((dr < 0.0 ? 0.0 : 1.0) - dr) / diff_r; double fit_r = ((dr < 0.0 ? 0.0 : 1.0) - dr) / diff_r;
double fit_g = ((dg < 0.0 ? 0.0 : 1.0) - dg) / diff_g; double fit_g = ((dg < 0.0 ? 0.0 : 1.0) - dg) / diff_g;
@ -774,27 +759,24 @@ void apply_color_blind_filter(Src & src, ColorBlindFilter const& op)
); );
adjust = std::max((fit_b > 1.0 || fit_b < 0.0) ? 0.0 : fit_b, adjust); adjust = std::max((fit_b > 1.0 || fit_b < 0.0) ? 0.0 : fit_b, adjust);
// Shift proportional to the greatest shift // Shift proportional to the greatest shift
dr = dr + (adjust * diff_r); dr += adjust * diff_r;
dg = dg + (adjust * diff_g); dg += adjust * diff_g;
db = db + (adjust * diff_b); db += adjust * diff_b;
// Apply gamma correction // Apply gamma correction
dr = std::pow(dr, 1.0 / 2.2); dr = std::pow(dr, inv_gamma);
dg = std::pow(dg, 1.0 / 2.2); dg = std::pow(dg, inv_gamma);
db = std::pow(db, 1.0 / 2.2); db = std::pow(db, inv_gamma);
// premultiply
dr *= da;
dg *= da;
db *= da;
// Clamp values // Clamp values
if(dr < 0.0) dr = 0.0; if(dr < 0.0 || std::isnan(dr)) dr = 0.0;
if(dr > 1.0) dr = 1.0; if(dr > 255.0) dr = 255.0;
if(dg < 0.0) dg = 0.0; if(dg < 0.0 || std::isnan(dg)) dg = 0.0;
if(dg > 1.0) dg = 1.0; if(dg > 255.0) dg = 255.0;
if(db < 0.0) db = 0.0; if(db < 0.0 || std::isnan(db)) db = 0.0;
if(db > 1.0) db = 1.0; if(db > 255.0) db = 255.0;
r = static_cast<uint8_t>(dr * 255.0); // premultiply
g = static_cast<uint8_t>(dg * 255.0); r = (static_cast<uint8_t>(dr) * a + 255) >> 8;
b = static_cast<uint8_t>(db * 255.0); g = (static_cast<uint8_t>(dg) * a + 255) >> 8;
b = (static_cast<uint8_t>(db) * a + 255) >> 8;
} }
} }
// set as premultiplied // set as premultiplied

2
test/data-visual

@ -1 +1 @@
Subproject commit d975838e0f6fa75cb3b3574b43ae205979508f67 Subproject commit a270d939f1b2b978203b9a91a3cdb4eff9f9f826

7
test/unit/imaging/image_filter.cpp
View file

@ -1,4 +1,3 @@
#include "catch.hpp" #include "catch.hpp"
// mapnik // mapnik
@ -482,7 +481,7 @@ SECTION("test color-blind-protanope") {
CHECK(im(0,0) == 0xff9a4a00); CHECK(im(0,0) == 0xff9a4a00);
CHECK(im(0,1) == 0xff006e7c); CHECK(im(0,1) == 0xff006e7c);
CHECK(im(1,0) == 0xffd9f6ff); CHECK(im(1,0) == 0xff00f7ff);
CHECK(im(1,1) == 0xff1d7e8e); CHECK(im(1,1) == 0xff1d7e8e);
} // END SECTION } // END SECTION
@ -499,7 +498,7 @@ SECTION("test color-blind-deuteranope") {
CHECK(im(0,0) == 0xff824f00); CHECK(im(0,0) == 0xff824f00);
CHECK(im(0,1) == 0xff1c688b); CHECK(im(0,1) == 0xff1c688b);
CHECK(im(1,0) == 0xffe9f5ff); CHECK(im(1,0) == 0xff27e9ff);
CHECK(im(1,1) == 0xff0077a0); CHECK(im(1,1) == 0xff0077a0);
} // END SECTION } // END SECTION
@ -516,7 +515,7 @@ SECTION("test color-blind-tritanope") {
CHECK(im(0,0) == 0xff595500); CHECK(im(0,0) == 0xff595500);
CHECK(im(0,1) == 0xff80763a); CHECK(im(0,1) == 0xff80763a);
CHECK(im(1,0) == 0xfff8f3ff); CHECK(im(1,0) == 0xfffeecff);
CHECK(im(1,1) == 0xff0017fd); CHECK(im(1,1) == 0xff0017fd);
} // END SECTION } // END SECTION