png2aa.cpp

#include <iostream>
#include <boost/gil/typedefs.hpp>
#include <boost/gil/extension/io/png.hpp>
#include <boost/gil/extension/io/png/old.hpp>

int main(int argc, char** argv)
{
    namespace g = boost::gil;

    if (argc <= 1)
        return -1;

    g::rgba8_image_t img;
    g::png_read_and_convert_image(argv[1], img);

    int scale = (img.width() + 79) / 80;
    g::dynamic_xy_step_type<g::rgba8_image_t::view_t>::type img_v(
        g::subsampled_view(g::view(img), scale, scale));

    for (g::rgba8_view_t::y_coord_t y = 0; y < img_v.height(); y += 2) {
        for (g::rgba8_view_t::x_coord_t x = 0; x < img_v.width(); ++x) {
            g::gray8_pixel_t gu, gl;

            color_convert(img_v(x, y), gu);

            if (y + 1 < img_v.height())
                color_convert(img_v(x, y + 1), gl);

            std::cout << " .,`:;\"!|"[gl / 86 + (gu / 86) * 3];
        }
        std::cout << std::endl;
    }

    return 0;
}