ceph/src/boost/libs/gil/test/core/image_processing/lanczos_scaling.cpp

   1 //
   2 // Copyright 2019 Olzhas Zhumabek <anonymous.from.applecity@gmail.com>
   3 //
   4 // Use, modification and distribution are subject to the Boost Software License,
   5 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt)
   7 //
   8 #include <boost/gil/image_processing/scaling.hpp>
   9 #include <boost/gil/image.hpp>
  10
  11 #include <boost/core/lightweight_test.hpp>
  12
  13
  14 #include <iostream>
  15
  16 namespace gil = boost::gil;
  17
  18 bool are_equal(gil::rgb8_view_t expected, gil::rgb8_view_t actual) {
  19     if (expected.dimensions() != actual.dimensions())
  20         return false;
  21
  22     for (long int y = 0; y < expected.height(); ++y)
  23     {
  24         for (long int x = 0; x < expected.width(); ++x)
  25         {
  26             if (expected(x, y) != actual(x, y))
  27             {
  28                 return false;
  29             }
  30         }
  31     }
  32
  33     return true;
  34 }
  35
  36 void test_lanczos_black_image()
  37 {
  38
  39     const gil::point_t input_dimensions(20, 20);
  40     const gil::point_t output_dimensions(input_dimensions.x / 2, input_dimensions.y / 2);
  41     gil::rgb8_image_t image(input_dimensions, gil::rgb8_pixel_t(0, 0, 0), 0);
  42     // fill with values other than 0
  43     gil::rgb8_image_t output_image(
  44         output_dimensions,
  45         gil::rgb8_pixel_t(100, 100, 100),
  46         0
  47     );
  48     gil::rgb8_image_t expected(
  49         output_dimensions,
  50         gil::rgb8_pixel_t(0, 0, 0),
  51         0
  52     );
  53
  54     auto view = gil::view(image);
  55     auto output_view = gil::view(output_image);
  56     auto expected_view = gil::view(expected);
  57     gil::scale_lanczos(view, output_view, 5);
  58     BOOST_TEST(are_equal(expected_view,output_view));
  59 }
  60
  61 void test_lanczos_response_on_zero()
  62 {
  63     //random value for a
  64     BOOST_TEST(gil::lanczos(0, 2) == 1);
  65 }
  66
  67 int main()
  68 {
  69     test_lanczos_black_image();
  70     test_lanczos_response_on_zero();
  71     return boost::report_errors();
  72 }