svoid test_ImageSimilarityAtScale(BufferedImage img1, BufferedImage img2, int featureSize, bool verbose default false) {
  ImageSimilarityAtScale algo = new(
    IntegralImage(img1), IntegralImage(img2), featureSize);
  algo.verbose = verbose;
  algo.run();
  do {
    print("Similarity: " + algo! + " after " + nBlocks(algo.blocksCalculated()) + " at " + algo.ps.lastExecutedProbability());
    // TODO print("Diffs at scale: " + .diffsAtScale);
  } while (algo.step());
}