def make_prototype(triangles, spot_based=True):
trans_triangles = []
for t in triangles:
# Centralize the triangle in the plane
t += np.array([250.0, 250.0]) - geometry.centroid(t)
# If non-spot-based pototype is requested, swap the vertices around so that vertex 1 is
# the pointiest one.
if spot_based == False:
angles = [geometry.angle(t,1), geometry.angle(t,2), geometry.angle(t,3)]
min_angle = angles.index(min(angles))
if min_angle == 0: t = np.array([t[0], t[1], t[2]])
elif min_angle == 1: t = np.array([t[1], t[2], t[0]])
elif min_angle == 2: t = np.array([t[2], t[0], t[1]])
# Rotate the triangle around its centroid so that vertex 1 points North
t = geometry.rotate(t)
# Ensure that vertex 2 is to the left of vertex 3 to prevent cancelling out
if t[1,0] > t[2,0]:
t = np.array([t[0], t[2], t[1]])
trans_triangles.append(t)
# Reformat as Numpy array and take the mean of the coordinates to form the prototype
trans_triangles = np.asarray(trans_triangles, dtype=float)
prototype = trans_triangles.mean(axis=0)
# Shift the prototype such that its bounding box is vertically centralized in the plane
prototype[:, 1] += ((500.0 - (max([prototype[1,1], prototype[2,1]]) - prototype[0,1])) / 2.0) - prototype[0,1]
return prototype
def location_distance(t1, t2): return geometry.ED(geometry.centroid(t1), geometry.centroid(t2))
if i == 0:
coords_last = np.nan
else:
coords_last = coords_current
# Create a list for the objects in the current frame
coords_current = [None] * len(indices)
# Loop over all shapes in this frame
for j, shape in enumerate(indices):
# Convert coordinates of annotation to numpy array
point_coords = np.asarray(annotation['shapes'][shape]['points'])
# Compute centroid
coords_current[j] = geometry.centroid(point_coords)
# Plot outline of current object annotation on the frame
plt.fill(point_coords[:,0], point_coords[:,1], \
facecolor='none', edgecolor=colors[shape])
# Plot the centroid
plt.plot(coords_current[j][0], coords_current[j][1], \
marker='o', color=colors[shape], \
label=annotation['shapes'][shape]['label'])
# Don't show axes
plt.axis('off')
# Show the legend
plt.legend()