1 #include <boost/gil/typedefs.hpp>
2 #include <boost/gil/image_processing/numeric.hpp>
3 #include <boost/gil/extension/io/png.hpp>
4 #include <boost/gil/extension/numeric/convolve.hpp>
5 #include <string>
6 #include <iostream>
7
8 namespace gil = boost::gil;
9
main(int argc,char * argv[])10 int main(int argc, char* argv[])
11 {
12 if (argc != 5)
13 {
14 std::cerr << "usage: " << argv[0] << ": <input.png> <sobel|scharr> <output-x.png> <output-y.png>\n";
15 return -1;
16 }
17
18 gil::gray8_image_t input_image;
19 gil::read_image(argv[1], input_image, gil::png_tag{});
20 auto input = gil::view(input_image);
21 auto filter_type = std::string(argv[2]);
22
23 gil::gray16_image_t dx_image(input_image.dimensions());
24 auto dx = gil::view(dx_image);
25 gil::gray16_image_t dy_image(input_image.dimensions());
26 auto dy = gil::view(dy_image);
27 if (filter_type == "sobel")
28 {
29 gil::detail::convolve_2d(input, gil::generate_dx_sobel(1), dx);
30 gil::detail::convolve_2d(input, gil::generate_dy_sobel(1), dy);
31 }
32 else if (filter_type == "scharr")
33 {
34 gil::detail::convolve_2d(input, gil::generate_dx_scharr(1), dx);
35 gil::detail::convolve_2d(input, gil::generate_dy_scharr(1), dy);
36 }
37 else
38 {
39 std::cerr << "unrecognized gradient filter type. Must be either sobel or scharr\n";
40 return -1;
41 }
42
43 gil::write_view(argv[3], dx, gil::png_tag{});
44 gil::write_view(argv[4], dy, gil::png_tag{});
45 }
46