Question: Python - Perspective transform for OpenCV from a rotation angle

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Python - Perspective transform for OpenCV from a rotation angle

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Added at 2017-01-02 14:01
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I'm working on depth map with OpenCV. I can obtain it but it is reconstructed from the left camera origin and there is a little tilt of this latter and as you can see on the figure, the depth is "shifted" (the depth should be close and no horizontal gradient):

enter image description here

I would like to express it as with a zero angle, i try with the warp perspective function as you can see below but i obtain a null field...

P = np.dot(cam,np.dot(Transl,np.dot(Rot,A1)))

dst = cv2.warpPerspective(depth, P, (2048, 2048))

with :

#Projection 2D -> 3D matrix
A1 = np.zeros((4,3))
A1[0,0] = 1 
A1[0,2] = -1024
A1[1,1] = 1
A1[1,2] = -1024
A1[3,2] = 1

#Rotation matrice around the Y axis
theta = np.deg2rad(5) 
Rot = np.zeros((4,4))
Rot[0,0] = np.cos(theta)
Rot[0,2] = -np.sin(theta)
Rot[1,1] = 1
Rot[2,0] = np.sin(theta)
Rot[2,2] = np.cos(theta)
Rot[3,3] = 1

#Translation matrix on the X axis 
dist = 0
Transl = np.zeros((4,4))
Transl[0,0] = 1 
Transl[0,2] = dist
Transl[1,1] = 1
Transl[2,2] = 1
Transl[3,3] = 1

#Camera Intrisecs matrix 3D -> 2D
cam = np.concatenate((C1,np.zeros((3,1))),axis=1)
cam[2,2] = 1
P = np.dot(cam,np.dot(Transl,np.dot(Rot,A1)))

dst = cv2.warpPerspective(Z0_0, P, (2048*3, 2048*3))

EDIT LATER :

You can download the 32MB field dataset here: https://filex.ec-lille.fr/get?k=cCBoyoV4tbmkzSV5bi6. Then, load and view the image with:

from matplotlib import pyplot as plt
import numpy as np

img = np.load('testZ0.npy')
plt.imshow(img)
plt.show()
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Python - Perspective transform for OpenCV from a rotation angle

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