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libs/gil/example/affine.cpp

//
// Copyright 2005-2007 Adobe Systems Incorporated
//
// Distributed under 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
//
#include <boost/gil.hpp>
#include <boost/gil/extension/io/jpeg.hpp>
#include <boost/gil/extension/numeric/sampler.hpp>
#include <boost/gil/extension/numeric/resample.hpp>

// Example for resample_pixels() in the numeric extension

int main()
{
    namespace gil = boost::gil;

    gil::rgb8_image_t img;
    gil::read_image("test.jpg", img, gil::jpeg_tag());

    // test resample_pixels
    // Transform the image by an arbitrary affine transformation using nearest-neighbor resampling
    gil::rgb8_image_t transf(gil::rgb8_image_t::point_t(gil::view(img).dimensions() * 2));
    gil::fill_pixels(gil::view(transf), gil::rgb8_pixel_t(255, 0, 0)); // the background is red

    gil::matrix3x2<double> mat =
        gil::matrix3x2<double>::get_translate(-gil::point<double>(200,250)) *
        gil::matrix3x2<double>::get_rotate(-15*3.14/180.0);
    gil::resample_pixels(const_view(img), gil::view(transf), mat, gil::nearest_neighbor_sampler());
    gil::write_view("out-affine.jpg", gil::view(transf), gil::jpeg_tag());

    return 0;
}