Merge pull request #673 from simmplecoder/gsoc_2020_fixup

* Fix Hough transform and move rasterization

Hough line transform had incorrect
rounding which lead to misleading message

* In depth explanation for Hough line

Added in depth explanation for
Hough line transform in the
associated markdown file

* Change "" includes into <>

* Move diffusion and Hough transform

Move anisotropic diffusion and
Hough transform into extension.
Adjust tests and cmakelists

* Edit Jamfile to new layout

* Add compile statements to Jamfile

* Remove migrated files

* Removed redundant lines

CMakeLists.txt

@@ -56,6 +56,8 @@ option(BOOST_GIL_ENABLE_EXT_DYNAMIC_IMAGE "Enable Dynamic Image extension, tests
 option(BOOST_GIL_ENABLE_EXT_IO "Enable IO extension, tests and examples (require libjpeg, libpng, libtiff)" ON)
 option(BOOST_GIL_ENABLE_EXT_NUMERIC "Enable Numeric extension, tests and examples" ON)
 option(BOOST_GIL_ENABLE_EXT_TOOLBOX "Enable Toolbox extension, tests and examples" ON)
+option(BOOST_GIL_ENABLE_EXT_RASTERIZATION "Enable Rasterization extension and tests" ON)
+option(BOOST_GIL_ENABLE_EXT_IMAGE_PROCESSING "Enable Image Processing extension (!) and tests" ON)
 option(BOOST_GIL_USE_CONAN "Use Conan to install dependencies" OFF)
 option(BOOST_GIL_USE_CLANG_TIDY "Set CMAKE_CXX_CLANG_TIDY property on targets to enable clang-tidy linting" OFF)
 set(CMAKE_CXX_STANDARD 11 CACHE STRING "C++ standard version to use (default is 11)")

example/anisotropic_diffusion.cpp

@@ -9,7 +9,7 @@
 #include <boost/gil/algorithm.hpp>
 #include <boost/gil/extension/io/png.hpp>
 #include <boost/gil/image.hpp>
-#include <boost/gil/image_processing/diffusion.hpp>
+#include "boost/gil/extension/image_processing/diffusion.hpp"
 #include <boost/gil/image_view.hpp>
 #include <boost/gil/io/typedefs.hpp>
 #include <boost/gil/typedefs.hpp>

example/histogram_equalization.md

@@ -7,6 +7,52 @@ Histogram equalization capabilities in GIL are demonstrated by the program `hist
 
 The program doesn't take any argument on the command line.
 
+Hough line transform solves the equation of a line in reverse, but in *polar coordinates*! The implementation will make each pixel vote on all possible lines it could be part of, limited by input Hough parameters.
+
+A line in polar coordinates is represented by normal to it in polar coordinates, as shown in example here 
+https://docs.opencv.org/3.4/d9/db0/tutorial_hough_lines.html
+
+Since real line is the diagonal throughout the image, the angle of normal to it will 45 degrees. (1s represent real line, 5s represent normal to it).
+
+```
+1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 
+0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 
+0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 
+0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 
+0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 
+0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 
+0 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 
+0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 
+5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 
+```
+
+It is obvious that the angle for the expected Hough transform is 45 degrees (angle between 5s and bottom 0s). Now we 
+need to find the length of 5s. Since 5s, 1s and bottom 0s form a right triangle, we know that bottom 0s are 32 in length
+and is a hypotenuse! Using trivial trigonometry we know that the length we are searching for is 32 * cos(45).  
+
 `histogram_equalization` expects to find an image called `test_adaptive.png` in the current directory, and produces an image in return, where the equalization have been applied: `histogram_gray_equalized.png`.
 
 ## Specific requirements

example/hough_transform_line.cpp

@@ -25,7 +25,7 @@ namespace gil = boost::gil;
 
 int main()
 {
-    std::ptrdiff_t size = 32;
+    const std::ptrdiff_t size = 32;
     gil::gray16_image_t input_image(size, size);
     auto input_view = gil::view(input_image);
 
@@ -52,7 +52,7 @@ int main()
     double _5_degrees = gil::detail::pi / 36;
     auto theta_parameter =
         gil::make_theta_parameter(_45_degrees, _5_degrees, input_view.dimensions());
-    auto expected_radius = static_cast<std::ptrdiff_t>(std::round(std::cos(_45_degrees) * size));
+    auto expected_radius = static_cast<std::ptrdiff_t>(std::floor(std::cos(_45_degrees) * size));
     auto radius_parameter =
         gil::hough_parameter<std::ptrdiff_t>::from_step_size(expected_radius, 7, 1);
     gil::gray32_image_t accumulator_array_image(theta_parameter.step_count,
@@ -70,6 +70,9 @@ int main()
                 theta_parameter.start_point + theta_index * theta_parameter.step_size;
             std::ptrdiff_t current_radius =
                 radius_parameter.start_point + radius_parameter.step_size * radius_index;
+            if (current_theta == _45_degrees && current_radius == expected_radius) {
+                std::cout << "* ";
+            }
             std::cout << "theta: " << current_theta << " radius: " << current_radius
                       << " accumulated value: " << accumulator_array(theta_index, radius_index)[0]
                       << '\n';

include/boost/gil.hpp

@@ -39,9 +39,9 @@
 #include <boost/gil/position_iterator.hpp>
 #include <boost/gil/premultiply.hpp>
 #include <boost/gil/promote_integral.hpp>
-#include <boost/gil/rasterization/circle.hpp>
-#include <boost/gil/rasterization/ellipse.hpp>
-#include <boost/gil/rasterization/line.hpp>
+#include <boost/gil/extension/rasterization/circle.hpp>
+#include <boost/gil/extension/rasterization/ellipse.hpp>
+#include <boost/gil/extension/rasterization/line.hpp>
 #include <boost/gil/rgb.hpp>
 #include <boost/gil/rgba.hpp>
 #include <boost/gil/step_iterator.hpp>
@@ -49,14 +49,14 @@
 #include <boost/gil/utilities.hpp>
 #include <boost/gil/virtual_locator.hpp>
 #include <boost/gil/image_processing/adaptive_histogram_equalization.hpp>
-#include <boost/gil/image_processing/diffusion.hpp>
+#include "boost/gil/extension/image_processing/diffusion.hpp"
 #include <boost/gil/image_processing/filter.hpp>
 #include <boost/gil/image_processing/harris.hpp>
 #include <boost/gil/image_processing/hessian.hpp>
 #include <boost/gil/image_processing/histogram_equalization.hpp>
 #include <boost/gil/image_processing/histogram_matching.hpp>
-#include <boost/gil/image_processing/hough_parameter.hpp>
-#include <boost/gil/image_processing/hough_transform.hpp>
+#include "boost/gil/extension/image_processing/hough_parameter.hpp"
+#include "boost/gil/extension/image_processing/hough_transform.hpp"
 #include <boost/gil/image_processing/morphology.hpp>
 #include <boost/gil/image_processing/numeric.hpp>
 #include <boost/gil/image_processing/scaling.hpp>

include/boost/gil/extension/image_processing/diffusion.hpp

@@ -10,7 +10,7 @@
 #ifndef BOOST_GIL_IMAGE_PROCESSING_DIFFUSION_HPP
 #define BOOST_GIL_IMAGE_PROCESSING_DIFFUSION_HPP
 
-#include "boost/gil/detail/math.hpp"
+#include <boost/gil/detail/math.hpp>
 #include <boost/gil/algorithm.hpp>
 #include <boost/gil/color_base_algorithm.hpp>
 #include <boost/gil/image.hpp>

include/boost/gil/extension/image_processing/hough_parameter.hpp

@@ -9,7 +9,7 @@
 #ifndef BOOST_GIL_IMAGE_PROCESSING_HOUGH_PARAMETER_HPP
 #define BOOST_GIL_IMAGE_PROCESSING_HOUGH_PARAMETER_HPP
 
-#include <boost/gil/point.hpp>
+#include "boost/gil/point.hpp"
 #include <cmath>
 #include <cstddef>
 

include/boost/gil/extension/image_processing/hough_transform.hpp

@@ -10,8 +10,8 @@
 #define BOOST_GIL_IMAGE_PROCESSING_HOUGH_TRANSFORM_HPP
 
 #include <algorithm>
-#include <boost/gil/image_processing/hough_parameter.hpp>
-#include <boost/gil/rasterization/circle.hpp>
+#include <boost/gil/extension/image_processing/hough_parameter.hpp>
+#include <boost/gil/extension/rasterization/circle.hpp>
 #include <cmath>
 #include <cstddef>
 #include <iterator>

test/core/CMakeLists.txt

@@ -39,5 +39,4 @@ add_subdirectory(image)
 add_subdirectory(image_view)
 add_subdirectory(algorithm)
 add_subdirectory(image_processing)
-add_subdirectory(histogram)
-add_subdirectory(rasterization)
+add_subdirectory(histogram)

test/core/Jamfile

@@ -33,4 +33,3 @@ build-project image_view ;
 build-project algorithm ;
 build-project image_processing ;
 build-project histogram ;
-build-project rasterization ;

test/core/image_processing/CMakeLists.txt

@@ -19,10 +19,6 @@ foreach(_name
     box_filter
     median_filter
     sobel_scharr
-    anisotropic_diffusion
-    hough_parameter
-    hough_line_transform
-    hough_circle_transform
     convolve
     convolve_2d
     convolve_cols

test/core/image_processing/Jamfile

@@ -21,9 +21,6 @@ run hessian.cpp ;
 run sobel_scharr.cpp ;
 run box_filter.cpp ;
 run median_filter.cpp ;
-run anisotropic_diffusion.cpp ;
-run hough_line_transform.cpp ;
-run hough_circle_transform.cpp ;
 run morphology.cpp ;
 run convolve.cpp ;
 run convolve_2d.cpp ;

test/extension/CMakeLists.txt

@@ -5,6 +5,14 @@
 # (See accompanying file LICENSE_1_0.txt or copy at
 # http://www.boost.org/LICENSE_1_0.txt)
 #
+if(BOOST_GIL_ENABLE_EXT_RASTERIZATION)
+  add_subdirectory(rasterization)
+endif()
+
+if(BOOST_GIL_ENABLE_EXT_IMAGE_PROCESSING)
+  add_subdirectory(image_processing)
+endif()
+
 if(BOOST_GIL_ENABLE_EXT_DYNAMIC_IMAGE)
   add_subdirectory(dynamic_image)
 endif()

test/extension/Jamfile

@@ -11,3 +11,5 @@ build-project histogram ;
 build-project numeric ;
 build-project toolbox ;
 build-project io ;
+build-project image_processing ;
+build-project rasterization ;

test/extension/image_processing/CMakeLists.txt

@@ -0,0 +1,22 @@
+foreach(_name
+        anisotropic_diffusion
+        hough_circle_transform
+        hough_line_transform
+        hough_parameter)
+    set(_test t_ext_image_processing_${_name})
+    set(_target test_ext_image_processing_${_name})
+
+    add_executable(${_target} "")
+    target_sources(${_target} PRIVATE ${_name}.cpp)
+    target_link_libraries(${_target}
+            PRIVATE
+            gil_compile_options
+            gil_include_directories
+            gil_dependencies)
+    target_compile_definitions(${_target} PRIVATE BOOST_GIL_USE_CONCEPT_CHECK)
+    add_test(NAME ${_test} COMMAND ${_target})
+
+    unset(_name)
+    unset(_target)
+    unset(_test)
+endforeach()

test/extension/image_processing/Jamfile

@@ -0,0 +1,14 @@
+# Boost.GIL (Generic Image Library) - tests
+#
+# Copyright 2020 Olzhas Zhumabek <anonymous.from.applecity@gmail.com>
+#
+# Use, modification and distribution are subject to the Boost Software License,
+# Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+#
+import testing ;
+
+run anisotropic_diffusion.cpp ;
+run hough_circle_transform.cpp ;
+run hough_line_transform.cpp ;
+run hough_parameter.cpp ;

test/extension/image_processing/anisotropic_diffusion.cpp

@@ -5,11 +5,11 @@
 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 //
-#include "../test_fixture.hpp"
-#include "boost/gil/algorithm.hpp"
+#include <core/test_fixture.hpp>
+#include <boost/gil/algorithm.hpp>
 #include <boost/gil/color_base_algorithm.hpp>
 #include <boost/gil/image.hpp>
-#include <boost/gil/image_processing/diffusion.hpp>
+#include <boost/gil/extension/image_processing/diffusion.hpp>
 #include <boost/gil/image_view.hpp>
 #include <boost/gil/pixel.hpp>
 #include <boost/gil/typedefs.hpp>

test/extension/image_processing/hough_circle_transform.cpp

@@ -9,7 +9,7 @@
 #include <boost/core/lightweight_test.hpp>
 
 #include <boost/gil/image.hpp>
-#include <boost/gil/image_processing/hough_transform.hpp>
+#include <boost/gil/extension/image_processing/hough_transform.hpp>
 #include <boost/gil/image_view.hpp>
 #include <boost/gil/typedefs.hpp>
 

test/extension/image_processing/hough_line_transform.cpp

@@ -10,10 +10,10 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/gil/detail/math.hpp>
 #include <boost/gil/image.hpp>
-#include <boost/gil/image_processing/hough_transform.hpp>
+#include <boost/gil/extension/image_processing/hough_transform.hpp>
 #include <boost/gil/image_view.hpp>
 #include <boost/gil/point.hpp>
-#include <boost/gil/rasterization/line.hpp>
+#include <boost/gil/extension/rasterization/line.hpp>
 #include <boost/gil/typedefs.hpp>
 #include <cmath>
 #include <cstddef>

test/extension/image_processing/hough_parameter.cpp

@@ -7,7 +7,7 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 //
 #include <boost/core/lightweight_test.hpp>
-#include <boost/gil/image_processing/hough_parameter.hpp>
+#include <boost/gil/extension/image_processing/hough_parameter.hpp>
 
 namespace gil = boost::gil;
 

test/extension/rasterization/circle.cpp

@@ -8,7 +8,7 @@
 //
 
 #include <boost/core/lightweight_test.hpp>
-#include <boost/gil/rasterization/circle.hpp>
+#include "boost/gil/extension/rasterization/circle.hpp"
 #include <cstddef>
 #include <vector>
 

test/extension/rasterization/ellipse.cpp

@@ -6,7 +6,7 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 //
 #include <boost/core/lightweight_test.hpp>
-#include <boost/gil.hpp>
+#include "boost/gil.hpp"
 #include <array>
 #include <cmath>
 #include <vector>

test/extension/rasterization/line.cpp

@@ -9,8 +9,8 @@
 
 #include <algorithm>
 #include <boost/core/lightweight_test.hpp>
-#include <boost/gil/point.hpp>
-#include <boost/gil/rasterization/line.hpp>
+#include "boost/gil/point.hpp"
+#include "boost/gil/extension/rasterization/line.hpp"
 
 #include <cmath>
 #include <cstddef>