I've implemented a dense optical flow algorithm and I want to visualize it with following color model
(color denotes direction of flow at some point, intensity denotes length of displacement vector)
I've implemented a dirty version of the visualization
def visualizeFlow(u, v):
colorModel = cv2.imread('../colormodel.png')
colorModelCenter = (colorModel.shape[0]/2, colorModel.shape[1]/2)
res = np.zeros((u.shape[0], u.shape[1], 3), dtype=np.uint8)
mag = np.max(np.sqrt(u**2 + v**2))
if mag == 0:
return res, colorModel
for i in xrange(res.shape[0]):
for j in xrange(res.shape[1]):
res[i, j] = colorModel[
colorModelCenter[0] + (v[i, j]/mag*colorModelCenter[0]),
colorModelCenter[1] + (u[i, j]/mag*colorModelCenter[1])
]
return res, colorModel
It produce nice in general case pictures but it really slow
So my question is can anyone help me make this visualization faster? If somebody knows a better way to visualize dense flow it may be cool
Code from OpenCV's tutorial:
import cv2
import numpy as np
# Use Hue, Saturation, Value colour model
hsv = np.zeros(im1.shape, dtype=np.uint8)
hsv[..., 1] = 255
mag, ang = cv2.cartToPolar(flow[..., 0], flow[..., 1])
hsv[..., 0] = ang * 180 / np.pi / 2
hsv[..., 2] = cv2.normalize(mag, None, 0, 255, cv2.NORM_MINMAX)
bgr = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
cv2.imshow("colored flow", bgr)
cv2.waitKey(0)
cv2.destroyAllWindows()