Python openCV cv2.calcOpticalFlowFarneback

Hi
I have problem with getting values for magnitude all other things is more then well, so here

i normalize my magnitude and i receive that its -nan(ind), if i remove this line all values are 0, but i start to code this in my laptop and all working well before, when i shift this project it to my office PC magnitude dissapear.
Thanks for any help

This is my mai function

[code]def onCook(scriptOp):

scriptOp.clear()

topRef = scriptOp.par.Top1.eval()
topRef2 = scriptOp.par.Top2.eval()

# default values
angle = []
magnitude = []

flowXY = []

hsv = np.zeros((op('img1').height, op('img1').width, 3))
one = topRef.numpyArray()
two = topRef2.numpyArray()
one_g = cv2.cvtColor(one, cv2.COLOR_RGB2GRAY)
two_g = cv2.cvtColor(two, cv2.COLOR_RGB2GRAY)

hsv[:,:,1] = cv2.cvtColor(two, cv2.COLOR_RGB2HSV)[:,:,1]

if topRef:

#//////////////////
	# read top as numpyArray
	#parametres = (prev, next, pyr_scale     (current:None), levels, winsize, iterations, poly_n, poly_sigma, flags[, flow]) → flow
	
	flowXY = cv2.calcOpticalFlowFarneback(one_g, two_g, None, 0.1,      10,        15 ,      15,        5,      1.2, 1)
	


# setup the scriptOp with 2 channels
# also set length to number of features that were detected

scriptOp.rate = me.time.rate
scriptOp.numSamples = (len(flowXY[:]))*(len(flowXY[1]))

an = scriptOp.appendChan('angle')
mg = scriptOp.appendChan('magnitude')

mag, ang = cv2.cartToPolar(flowXY[..., 0], flowXY[..., 1])		


hsv[:,:,0] = ang * (180/ np.pi / 2)
hsv[:,:,2] = cv2.normalize(mag,None,0,255,cv2.NORM_MINMAX)

hsv = np.asarray(hsv, dtype= np.float32)

rgb_flow = cv2.cvtColor(hsv,cv2.COLOR_HSV2RGB)

for row in range(len(hsv)):
	for col in range(len(hsv[0])):
		angle.append(hsv[row][col][0])
		magnitude.append(hsv[row][col][2])
		
an.vals = angle
mg.vals = magnitude


return[/code]