List<URI> layerGraphics = (List<URI>) values.getObject("overviewMapLayerGraphics", List.class);
assertEquals(3, layerGraphics.size());
final BufferedImage actualImage = ImageSimilarity.mergeImages(layerGraphics, 300, 200);
// ImageIO.write(actualImage, "tiff", new File("e:/tmp/expectedSimpleImage.tiff"));
new ImageSimilarity(actualImage, 2)
.assertSimilarity(getFile(BASE_DIR + "expectedSimpleImage.tiff"), 50);
}