DenseOpticalFlow - Shape problems
Hi all,
I am working on a project where I have to implement the DOF algorithm: calcOpticalFlowFarneback().
I've followed the opencv tutorial and it works very well with .avi files.
The "problem" is that I have to use .tif image sequences. As you can see in the tutorial he's using gray image and my .tif are already gray-scale but the algorithm doesn't like the shape of the calculated magnitude and phase:
-Tiff Extraction:
VideoToSOF = [0 for _ in range(len(images))]
print("Extracting frames..")
VideoFrameCounter = 0
for image in images:
VideoToSOF[VideoFrameCounter] = image
VideoFrameCounter += 1
print("Video Frame n°%d/%d" % (VideoFrameCounter,len(images)),end='\r')
-DOF Code:
frame2 = VideoToSOF[counter]
next = frame2
flow = cv2.calcOpticalFlowFarneback(prvs,next, flow, pyr_scale, levels, winsize, iteration, poly_n, poly_sigma, flags)
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)
As you can see my code is totally equal to the tutorial's one. Anyway i get this error:
Traceback (most recent call last): File ".\varioustest_script.py", line 73, in <module> hsv[...,0] = ang*180/np.pi/2 ValueError: could not broadcast input array from shape (300,300) into shape (300)
Do you know Why? I mean, the image should have the same shape as the .avi one..I don't get it!
where/how do you construct
hsv?what do you want to do with the optflow ? (the hsv is only for visualization)
I've followed the tutorial. Here's how i construct the HSV.
HSV is only for visual: yes, but why it gives me this error? The size of frames, 'mag' and 'ang' are all the same if I use .avi or .tif.
I can avoid real-time image show but I would like to see it!
I want to use OptFlow to analyze phase and mag of the .tif I give to it
if frame1 is a grayscale tiff, your hsv only has a single channel, too