void WindowAdapterTest::testWindowAdapter() {
debug(LOG_DEBUG, DEBUG_LOG, 0, "window adapter test");
// create an image
Image<unsigned char> image(16, 16);
for (unsigned int x = 0; x < 16; x++) {
for (unsigned int y = 0; y < 16; y++) {
image.pixel(x, y) = x * y;
}
}
// create the subframe
ImageRectangle frame(ImagePoint(4, 4), ImageSize(8, 8));
debug(LOG_DEBUG, DEBUG_LOG, 0, "frame: %s", frame.toString().c_str());
// create an adapter for a subframe
WindowAdapter<unsigned char> adapter(image, frame);
// access the subframe
ImageSize size = adapter.getSize();
debug(LOG_DEBUG, DEBUG_LOG, 0, "adapter size: %s",
size.toString().c_str());
for (int x = 0; x < size.width(); x++) {
for (int y = 0; y < size.height(); y++) {
unsigned char value = adapter.pixel(x, y);
unsigned char v
= (frame.origin().x() + x) * (frame.origin().y() + y);
if (v != value) {
debug(LOG_DEBUG, DEBUG_LOG, 0, "expected %d != %d found",
(int)v, (int)value);
}
CPPUNIT_ASSERT(value == v);
}
}
debug(LOG_DEBUG, DEBUG_LOG, 0, "window adapter test complete");
}
/**
* \brief Compute size of the complex fourier transform image
*
* We are using the real data DFTs from the fftw3 library, which uses a layout
* different from what you would expect from our image types. When going
* through a pixel array In our image types, the quickly increasing
* coordinate is the horizontal coordinate, which we usually call the
* x coordinate, and which is also the first coordinate. In FFTW3, the slowly
* increasing coordinate when going through the FFT array is the second
* coordinate. So if an image has width w and height h, then we have
* treat it as a data array with n0 = h and n1 = w. The corresponding
* fourier transform array for the real data transforms then has dimensions
* n0 and (n1/2 + 1). But since again the second coordinate is the one that
* increases quickly, we have to create an image of width (n1/2 + 1) and
* height n0.
*
* All this is unimportant as long as we don't look at the fourier transform
* as an image in its own right. Only then does it become important how we
* interpret the coordinates.
*
* \param size size of the image to be fourier transformed
*/
ImageSize FourierImage::fsize(const ImageSize& size) {
int w = size.width();
int h = size.height();
int n0 = h;
int n1 = w;
ImageSize result(2 * (1 + n1 / 2), n0);
debug(LOG_DEBUG, DEBUG_LOG, 0, "fourier image size %s -> %s",
size.toString().c_str(), result.toString().c_str());
return result;
}
