nanopyx.core.transform.image_shift_rotate

 1"""
 2Combination of functions for rotating an image over an arbitrary center, using several interpolation methods.
 3"""
 4
 5from scipy.ndimage import rotate
 6import numpy as np
 7
 8from ..utils.timeit import timeit2
 9from . import interpolation_bicubic
10from . import interpolation_bilinear
11from . import interpolation_nearest_neighbor
12from . import interpolation_catmull_rom
13from . import interpolation_lanczos
14
15from skimage.transform import AffineTransform, warp
16import cv2
17
18@timeit2
19def catmull_rom_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
20    interpolator = interpolation_catmull_rom.Interpolator(image)
21    return interpolator.rotate(angle, cx, cy)
22
23
24@timeit2
25def lanczos_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
26    interpolator = interpolation_lanczos.Interpolator(image)
27    return interpolator.rotate(angle, cx, cy)
28
29
30@timeit2
31def bicubic_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
32    interpolator = interpolation_bicubic.Interpolator(image)
33    return interpolator.rotate(angle, cx, cy)
34
35
36@timeit2
37def bilinear_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
38    interpolator = interpolation_bilinear.Interpolator(image)
39    return interpolator.rotate(angle, cx, cy)
40
41
42@timeit2
43def nearest_neighbor_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
44    interpolator = interpolation_nearest_neighbor.Interpolator(image)
45    return interpolator.rotate(angle, cx, cy)
46
47
48#def scipy_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
49#scipy does not have a simple rotation around an arbitrary point which preserves image size
50#shift + rotation + shift would work but we lose information
51
52@timeit2
53def skimage_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
54    rotation = AffineTransform(rotation=angle)
55    shift2center = AffineTransform(translation=-np.array([cx, cy]))
56    shift2og = AffineTransform(translation=np.array([cx, cy]))
57    return warp(image, shift2center + rotation + shift2og)
58
59
60@timeit2
61def cv2_rotate_shift(image: np.ndarray, angle:float, cx:float, cy:float):
62    rotmat = cv2.getRotationMatrix2D(np.array([cx,cy]), np.rad2deg(angle), 1)
63    return cv2.warpAffine(image, rotmat, image.shape[:2][::-1])