File size: 5,617 Bytes
af44a4b
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
import numpy as np
import cv2
from .helper import gen_lensmask


def brightness_brighten_shfit_HSV(img, severity=1):
    """
    The RGB image is mapping to HSV, and then enhance the brightness by V channel
    severity=[1,2,3,4,5] is corresponding to c=[0.1, 0.2, 0.3, 0.4, 0.5]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    c = [0.1, 0.2, 0.3, 0.4, 0.5][severity-1]
    img = np.float32(np.array(img) / 255.)
    img_hsv = cv2.cvtColor(img, cv2.COLOR_RGB2HSV)
    img_hsv[:, :, 2] += c
    img_lq = cv2.cvtColor(img_hsv, cv2.COLOR_HSV2RGB)
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_brighten_shfit_RGB(img, severity=1):
    """
    The RGB image is directly enhanced by RGB mean shift
    severity=[1,2,3,4,5] is corresponding to c=[0.1, 0.15, 0.2, 0.27, 0.35]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    c = [0.1, 0.15, 0.2, 0.27, 0.35][severity-1]
    img = np.float32(np.array(img) / 255.)
    img_lq = img + c
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_brighten_gamma_RGB(img, severity=1):
    """
    The RGB image is enhanced by V channel with a gamma function
    severity=[1,2,3,4,5] is corresponding to gamma=[0.8, 0.7, 0.6, 0.45, 0.3]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    gamma = [0.8, 0.7, 0.6, 0.45, 0.3][severity-1]
    img = np.array(img / 255.)
    img_lq = img ** gamma
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_brighten_gamma_HSV(img, severity=1):
    """
    The RGB image is enhanced by V channel with a gamma function
    severity=[1,2,3,4,5] is corresponding to gamma=[0.7, 0.55, 0.4, 0.25, 0.1]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    gamma = [0.7, 0.58, 0.47, 0.36, 0.25][severity-1]
    img_hsv = cv2.cvtColor(img, cv2.COLOR_RGB2HSV)
    img_hsv = np.array(img_hsv / 255.)
    img_hsv[:, :, 2] = img_hsv[:, :, 2] ** gamma
    img_lq = np.uint8(np.clip(img_hsv, 0, 1) * 255.)
    img_lq = cv2.cvtColor(img_lq, cv2.COLOR_HSV2RGB)
    return img_lq


def brightness_darken_shfit_HSV(img, severity=1):
    """
    The RGB image is mapping to HSV, and then darken the brightness by V channel
    severity=[1,2,3,4,5] is corresponding to c=[0.1, 0.2, 0.3, 0.4, 0.5]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    c = [0.1, 0.2, 0.3, 0.4, 0.5][severity-1]
    img = np.float32(np.array(img) / 255.)
    img_hsv = cv2.cvtColor(img, cv2.COLOR_RGB2HSV)
    img_hsv[:, :, 2] -= c
    img_lq = cv2.cvtColor(img_hsv, cv2.COLOR_HSV2RGB)
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_darken_shfit_RGB(img, severity=1):
    """
    The RGB image's brightness is directly reduced by RGB mean shift
    severity=[1,2,3,4,5] is corresponding to c=[0.1, 0.15, 0.2, 0.27, 0.35]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    c = [0.1, 0.15, 0.2, 0.27, 0.35][severity-1]
    img = np.float32(np.array(img)/255.)
    img_lq = img - c
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_darken_gamma_RGB(img, severity=1):
    """
    The RGB image is darkened by V channel with a gamma function
    severity=[1,2,3,4,5] is corresponding to gamma=[1.4, 1.7, 2.1, 2.6, 3.2]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    gamma = [1.4, 1.7, 2.1, 2.6, 3.2][severity-1]
    img = np.array(img / 255.)
    img_lq = img ** gamma
    return np.uint8(np.clip(img_lq, 0, 1) * 255.)


def brightness_darken_gamma_HSV(img, severity=1):
    """
    The RGB image is enhanced by V channel with a gamma function
    severity=[1,2,3,4,5] is corresponding to gamma=[1.5, 1.8, 2.2, 2.7, 3.5]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    gamma = [1.5, 1.8, 2.2, 2.7, 3.5][severity-1]
    img_hsv = cv2.cvtColor(img, cv2.COLOR_RGB2HSV)
    img_hsv = np.array(img_hsv / 255.)
    img_hsv[:, :, 2] = img_hsv[:, :, 2] ** gamma
    img_lq = np.uint8(np.clip(img_hsv, 0, 1) * 255.)
    img_lq = cv2.cvtColor(img_lq, cv2.COLOR_HSV2RGB)
    return img_lq


def brightness_vignette(img, severity=1):
    """
    The RGB image is suffered from the vignette effect.
    severity=[1,2,3,4,5] is corresponding to gamma=[0.5, 0.875, 1.25, 1.625, 2]

    @param img: Input image, H x W x RGB, value range [0, 255]
    @param severity: Severity of distortion, [1, 5]
    @return: Degraded image, H x W x RGB, value range [0, 255]
    """
    gamma = [0.5, 0.875, 1.25, 1.625, 2][severity - 1]
    img = np.array(img)
    h, w = img.shape[:2]
    mask = gen_lensmask(h, w, gamma=gamma)[:, :, None]
    img_lq = mask * img
    return np.uint8(np.clip(img_lq, 0, 255))