reproduce_opencv_bug_uint16_more_than_4_channels_affine_transform.py

import cv2
import numpy as np

def base_tens_stats(tens):
    print(f'shape={tens.shape} min={tens.min()} mean={tens.mean()} max={tens.max()}')

x = np.random.randint(0,1020, (256,256,20)).astype(np.uint16)

base_tens_stats(x)

M = np.array([[ -9.86677170e-01,  -3.59121144e-01,   4.28262177e+02],
       [  3.59121144e-01,  -9.86677170e-01,   3.36327148e+02],
       [  0.00000000e+00,   0.00000000e+00,   1.00000000e+00]], dtype=np.float32)

y = cv2.warpAffine(x, M[:2,:],  x.shape[:2],
                                   borderMode=cv2.BORDER_CONSTANT,
                                   borderValue=0,
                                   flags=cv2.INTER_NEAREST)

print('after transform 1')
base_tens_stats(y)

y = cv2.warpAffine(x, M[:2,:],  x.shape[:2],
                                   borderMode=cv2.BORDER_CONSTANT,
                                   borderValue=0,
                                   flags=cv2.INTER_LINEAR)

print('after transform 2')
base_tens_stats(y)