def run_ransac(image): # TODO comment # TODO vizualize this image_l = image.load() width, height = image.size data = [] for y in xrange(0, height): for x in xrange(0, width): if image_l[x, y] > 128: data.append((x, y)) if y < 30: data.append((width - x, y + height)) dist = 3 [(line, points), (line2, points2)] = ransac.ransac_multi(2, data, dist, 250) line_to_points = lambda (a, b, c), x: (x, (a*x + c) / (- b)) # TODO width should not be here vvv # TODO refactor gridf to use standard equations instead of points line = [line_to_points(line, 0), line_to_points(line, width - 1)] line2 = [line_to_points(line2, 0), line_to_points(line2, width - 1)] return [sorted(points), sorted(points2)], line, line2
def find(lines, size, l1, l2, bounds, hough, show_all, do_something, logger): """Find the best grid given the *lines* and *size* of the image. Last three parameters serves for debugging, *l1*, *l2*, *bounds* and *hough* are here for compatibility with older version of gridf, so they can be easily exchanged, tested and compared. """ new_lines1 = map(lambda l: Line.from_ad(l, size), lines[0]) new_lines2 = map(lambda l: Line.from_ad(l, size), lines[1]) for l1 in new_lines1: for l2 in new_lines2: p = Point(intersection(l1, l2)) p.l1 = l1 p.l2 = l2 l1.points.append(p) l2.points.append(p) points = [l.points for l in new_lines1] def dst_p(x, y): x = x - size[0] / 2 y = y - size[1] / 2 return sqrt(x * x + y * y) for n_tries in xrange(3): logger("finding the diagonals") model = Diagonal_model(points) diag_lines = ransac.ransac_multi(6, points, 2, params.ransac_diagonal_iter, model=model) diag_lines = [l[0] for l in diag_lines] centers = [] cen_lin = [] for i in xrange(len(diag_lines)): line1 = diag_lines[i] for line2 in diag_lines[i+1:]: c = intersection(line1, line2) if c and dst_p(*c) < min(size) / 2: cen_lin.append((line1, line2, c)) centers.append(c) if show_all: import matplotlib.pyplot as pyplot from PIL import Image def plot_line_g((a, b, c), max_x): find_y = lambda x: - (c + a * x) / b pyplot.plot([0, max_x], [find_y(0), find_y(max_x)], color='b') fig = pyplot.figure(figsize=(8, 6)) for l in diag_lines: plot_line_g(l, size[0]) pyplot.scatter(*zip(*sum(points, []))) if len(centers) >= 1: pyplot.scatter([c[0] for c in centers], [c[1] for c in centers], color='r') pyplot.xlim(0, size[0]) pyplot.ylim(0, size[1]) pyplot.gca().invert_yaxis() fig.canvas.draw() size_f = fig.canvas.get_width_height() buff = fig.canvas.tostring_rgb() image_p = Image.fromstring('RGB', size_f, buff, 'raw') do_something(image_p, "finding diagonals") logger("finding the grid") data = sum(points, []) # TODO what if lines are missing? sc = float("inf") grid = None for (line1, line2, c) in cen_lin: diag1 = Line(line1) diag1.points = ransac.filter_near(data, diag1, 2) diag2 = Line(line2) diag2.points = ransac.filter_near(data, diag2, 2) grids = list(gen_corners(diag1, diag2, min(size) / 3)) try: new_sc, new_grid = min(map(lambda g: (score(sum(g, []), data), g), grids)) if new_sc < sc: sc, grid = new_sc, new_grid except ValueError: pass if grid: break