File size: 5,691 Bytes
c4d7a2b
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
155
156
157
import os
import random
import numpy as np
import pandas as pd
from PIL import Image
from torchvision import datasets, transforms, io
import torch


def get_random_texture(dataset_occluder):
    index = random.randint(0, len(dataset_occluder) - 1)
    texture_path, texture_class_index = dataset_occluder.imgs[index]
    texture_class = dataset_occluder.classes[texture_class_index]

    # Load the texture with the alpha channel
    texture = io.read_image(texture_path, mode=io.image.ImageReadMode.RGB_ALPHA)

    return texture, texture_class

def resize_occluder(occluder_pil, target_area, image_width, image_height):
    alpha = np.array(occluder_pil.getchannel('A'))
    non_transparent_area = np.count_nonzero(alpha > 0)

    area_scale_factor = target_area / non_transparent_area

    width_scale_factor = np.sqrt(area_scale_factor * (occluder_pil.width / occluder_pil.height))
    height_scale_factor = np.sqrt(area_scale_factor * (occluder_pil.height / occluder_pil.width))

    new_width = occluder_pil.width * width_scale_factor
    new_height = occluder_pil.height * height_scale_factor

    resized_occluder = occluder_pil.resize((int(new_width), int(new_height)), Image.LANCZOS)

    return resized_occluder

def randomly_rotate_occluder(occluder_pil):
    angle = random.uniform(-180, 180)
    return occluder_pil.rotate(angle, resample=Image.BICUBIC, expand=True)

def try_rotations(occluder_pil, image_pil, target_area):
    best_occluder = None
    best_area = 0
    best_pos = None
    for _ in range(10):
        rotated = randomly_rotate_occluder(occluder_pil)
        resized = resize_occluder(rotated, target_area, image_pil.width, image_pil.height)
        if resized.width > image_pil.width or resized.height > image_pil.height:
            pos = (image_pil.width // 2 - resized.width // 2, 
                   image_pil.height // 2 - resized.height // 2)
        else:
            max_x = max(0, image_pil.width - resized.width)
            max_y = max(0, image_pil.height - resized.height)
            pos = (random.randint(0, max_x), random.randint(0, max_y))

        mask = Image.new('1', image_pil.size)
        mask.paste(resized.getchannel('A'), pos, resized.getchannel('A'))
        area = np.count_nonzero(np.array(mask))

        if area > best_area:
            best_area = area
            best_occluder = resized
            best_pos = pos
    return best_occluder, best_pos


def occlude_image(image, occluder_tensor, percentage_occlusion, occluded_dir, img_name):
    occluder_pil = transforms.ToPILImage(mode='RGBA')(occluder_tensor)
    image_pil = transforms.ToPILImage()(image)

    target_area = image_pil.width * image_pil.height * percentage_occlusion
    occluder_pil, pos = try_rotations(occluder_pil, image_pil, target_area)

    image_pil.paste(occluder_pil, pos, occluder_pil)
    image_with_occluder_tensor = transforms.ToTensor()(image_pil)

    occluder_alpha = occluder_pil.getchannel('A')
    binary_mask = Image.new('1', image_pil.size)
    binary_mask.paste(occluder_alpha, pos, occluder_alpha)

    mask_array = np.array(binary_mask)
    mask_path = os.path.join(occluded_dir, f"{img_name}_mask.npy")
    np.save(mask_path, mask_array)

    return image_with_occluder_tensor, mask_path, pos


def rebuild_display_mask(image_path, mask_path):
    image_pil = Image.open(image_path)
    binary_mask = Image.new('1', image_pil.size)

    mask_array = np.load(mask_path)
    mask_indices = np.transpose(np.nonzero(mask_array))

    for i, j in mask_indices:
        binary_mask.putpixel((j, i), 1)

    binary_mask.show()


def build_dataset(data_path, transform):
    dataset = datasets.ImageFolder(data_path, transform=transform)
    nb_classes = len(dataset.classes)
    return dataset, nb_classes

def build_transform():
    t = []
    t.append(transforms.ToTensor())
    return transforms.Compose(t)

def main():
    data_dir = 'imagenet1'
    texture_dir = 'occluders_segmented'
    occluded_data_dir = 'imagenet_occluded'

    transform = build_transform()
    dataset, nb_classes = build_dataset(data_dir, transform)
    dataset_occluder, _ = build_dataset(texture_dir, transform)

    occlusion_info = pd.DataFrame(columns=["image_name", "class_name", "occluder_class",
                                           "percentage_occlusion", "mask", "pos"])

    for idx in range(len(dataset)):
        image, label = dataset[idx]
        category = dataset.classes[label]

        in_dir = os.path.join(data_dir, category)
        occluded_dir = os.path.join(occluded_data_dir, category)

        os.makedirs(occluded_dir, exist_ok=True)

        img_name = dataset.imgs[idx][0].split('/')[-1].split('.')[0]

        occluder_tensor, occluder_class = get_random_texture(dataset_occluder)
        occluded_image, mask_path, pos = occlude_image(image, occluder_tensor, 0.3, occluded_dir, img_name)

        mask_array = np.load(mask_path)
        actual_percentage_occlusion = np.count_nonzero(mask_array) / (image.shape[1] * image.shape[2])

        occluded_image_path = os.path.join(occluded_dir, f"{img_name}_occluded.png")
        transforms.ToPILImage()(occluded_image).save(occluded_image_path)

        new_row = pd.DataFrame({
            "image_name": [f"{img_name}_occluded.png"],
            "class_name": [category],
            "occluder_class": [occluder_class],
            "percentage_occlusion": [actual_percentage_occlusion],
            "mask": [mask_path],
            "pos": [pos]
        })

        occlusion_info = pd.concat([occlusion_info, new_row], ignore_index=True)

    occlusion_info.to_csv(os.path.join(occluded_data_dir, "occlusion_info.csv"), index=False)

if __name__ == "__main__":
    main()