File size: 5,507 Bytes
78ab311
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
152
153
154
# MIT License

# Copyright (c) 2022 Intelligent Systems Lab Org

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

# File author: Shariq Farooq Bhat

import numpy as np
from dataclasses import dataclass
from typing import Tuple, List

# dataclass to store the crop parameters
@dataclass
class CropParams:
    top: int
    bottom: int
    left: int
    right: int



def get_border_params(rgb_image, tolerance=0.1, cut_off=20, value=0, level_diff_threshold=5, channel_axis=-1, min_border=5) -> CropParams:
    gray_image = np.mean(rgb_image, axis=channel_axis)
    h, w = gray_image.shape


    def num_value_pixels(arr):
        return np.sum(np.abs(arr - value) < level_diff_threshold)

    def is_above_tolerance(arr, total_pixels):
        return (num_value_pixels(arr) / total_pixels) > tolerance

    # Crop top border until number of value pixels become below tolerance
    top = min_border
    while is_above_tolerance(gray_image[top, :], w) and top < h-1:
        top += 1
        if top > cut_off:
            break

    # Crop bottom border until number of value pixels become below tolerance
    bottom = h - min_border
    while is_above_tolerance(gray_image[bottom, :], w) and bottom > 0:
        bottom -= 1
        if h - bottom > cut_off:
            break

    # Crop left border until number of value pixels become below tolerance
    left = min_border
    while is_above_tolerance(gray_image[:, left], h) and left < w-1:
        left += 1
        if left > cut_off:
            break

    # Crop right border until number of value pixels become below tolerance
    right = w - min_border
    while is_above_tolerance(gray_image[:, right], h) and right > 0:
        right -= 1
        if w - right > cut_off:
            break
        

    return CropParams(top, bottom, left, right)


def get_white_border(rgb_image, value=255, **kwargs) -> CropParams:
    """Crops the white border of the RGB.

    Args:
        rgb: RGB image, shape (H, W, 3).
    Returns:
        Crop parameters.
    """
    if value == 255:
        # assert range of values in rgb image is [0, 255]
        assert np.max(rgb_image) <= 255 and np.min(rgb_image) >= 0, "RGB image values are not in range [0, 255]."
        assert rgb_image.max() > 1, "RGB image values are not in range [0, 255]."
    elif value == 1:
        # assert range of values in rgb image is [0, 1]
        assert np.max(rgb_image) <= 1 and np.min(rgb_image) >= 0, "RGB image values are not in range [0, 1]."

    return get_border_params(rgb_image, value=value, **kwargs)

def get_black_border(rgb_image, **kwargs) -> CropParams:
    """Crops the black border of the RGB.

    Args:
        rgb: RGB image, shape (H, W, 3).

    Returns:
        Crop parameters.
    """

    return get_border_params(rgb_image, value=0, **kwargs)

def crop_image(image: np.ndarray, crop_params: CropParams) -> np.ndarray:
    """Crops the image according to the crop parameters.

    Args:
        image: RGB or depth image, shape (H, W, 3) or (H, W).
        crop_params: Crop parameters.

    Returns:
        Cropped image.
    """
    return image[crop_params.top:crop_params.bottom, crop_params.left:crop_params.right]

def crop_images(*images: np.ndarray, crop_params: CropParams) -> Tuple[np.ndarray]:
    """Crops the images according to the crop parameters.

    Args:
        images: RGB or depth images, shape (H, W, 3) or (H, W).
        crop_params: Crop parameters.

    Returns:
        Cropped images.
    """
    return tuple(crop_image(image, crop_params) for image in images)

def crop_black_or_white_border(rgb_image, *other_images: np.ndarray, tolerance=0.1, cut_off=20, level_diff_threshold=5) -> Tuple[np.ndarray]:
    """Crops the white and black border of the RGB and depth images.

    Args:
        rgb: RGB image, shape (H, W, 3). This image is used to determine the border.
        other_images: The other images to crop according to the border of the RGB image.
    Returns:
        Cropped RGB and other images.
    """
    # crop black border
    crop_params = get_black_border(rgb_image, tolerance=tolerance, cut_off=cut_off, level_diff_threshold=level_diff_threshold)
    cropped_images = crop_images(rgb_image, *other_images, crop_params=crop_params)

    # crop white border
    crop_params = get_white_border(cropped_images[0], tolerance=tolerance, cut_off=cut_off, level_diff_threshold=level_diff_threshold)
    cropped_images = crop_images(*cropped_images, crop_params=crop_params)

    return cropped_images