File size: 7,051 Bytes
749745d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
import torch

import pycocotools.mask as mask_utils

# transpose
FLIP_LEFT_RIGHT = 0
FLIP_TOP_BOTTOM = 1


class Mask(object):
    """

    This class is unfinished and not meant for use yet

    It is supposed to contain the mask for an object as

    a 2d tensor

    """

    def __init__(self, masks, size, mode):
        self.masks = masks
        self.size = size
        self.mode = mode

    def transpose(self, method):
        if method not in (FLIP_LEFT_RIGHT, FLIP_TOP_BOTTOM):
            raise NotImplementedError("Only FLIP_LEFT_RIGHT and FLIP_TOP_BOTTOM implemented")

        width, height = self.size
        if method == FLIP_LEFT_RIGHT:
            dim = width
            idx = 2
        elif method == FLIP_TOP_BOTTOM:
            dim = height
            idx = 1

        flip_idx = list(range(dim)[::-1])
        flipped_masks = self.masks.index_select(dim, flip_idx)
        return Mask(flipped_masks, self.size, self.mode)

    def crop(self, box):
        w, h = box[2] - box[0], box[3] - box[1]

        cropped_masks = self.masks[:, box[1] : box[3], box[0] : box[2]]
        return Mask(cropped_masks, size=(w, h), mode=self.mode)

    def resize(self, size, *args, **kwargs):
        pass


class Polygons(object):
    """

    This class holds a set of polygons that represents a single instance

    of an object mask. The object can be represented as a set of

    polygons

    """

    def __init__(self, polygons, size, mode):
        # assert isinstance(polygons, list), '{}'.format(polygons)
        if isinstance(polygons, list):
            polygons = [torch.as_tensor(p, dtype=torch.float32) for p in polygons]
        elif isinstance(polygons, Polygons):
            polygons = polygons.polygons

        self.polygons = polygons
        self.size = size
        self.mode = mode

    def transpose(self, method):
        if method not in (FLIP_LEFT_RIGHT, FLIP_TOP_BOTTOM):
            raise NotImplementedError("Only FLIP_LEFT_RIGHT and FLIP_TOP_BOTTOM implemented")

        flipped_polygons = []
        width, height = self.size
        if method == FLIP_LEFT_RIGHT:
            dim = width
            idx = 0
        elif method == FLIP_TOP_BOTTOM:
            dim = height
            idx = 1

        for poly in self.polygons:
            p = poly.clone()
            TO_REMOVE = 1
            p[idx::2] = dim - poly[idx::2] - TO_REMOVE
            flipped_polygons.append(p)

        return Polygons(flipped_polygons, size=self.size, mode=self.mode)

    def crop(self, box):
        w, h = box[2] - box[0], box[3] - box[1]

        # TODO chck if necessary
        w = max(w, 1)
        h = max(h, 1)

        cropped_polygons = []
        for poly in self.polygons:
            p = poly.clone()
            p[0::2] = p[0::2] - box[0]  # .clamp(min=0, max=w)
            p[1::2] = p[1::2] - box[1]  # .clamp(min=0, max=h)
            cropped_polygons.append(p)

        return Polygons(cropped_polygons, size=(w, h), mode=self.mode)

    def resize(self, size, *args, **kwargs):
        ratios = tuple(float(s) / float(s_orig) for s, s_orig in zip(size, self.size))
        if ratios[0] == ratios[1]:
            ratio = ratios[0]
            scaled_polys = [p * ratio for p in self.polygons]
            return Polygons(scaled_polys, size, mode=self.mode)

        ratio_w, ratio_h = ratios
        scaled_polygons = []
        for poly in self.polygons:
            p = poly.clone()
            p[0::2] *= ratio_w
            p[1::2] *= ratio_h
            scaled_polygons.append(p)

        return Polygons(scaled_polygons, size=size, mode=self.mode)

    def convert(self, mode):
        width, height = self.size
        if mode == "mask":
            rles = mask_utils.frPyObjects([p.detach().numpy() for p in self.polygons], height, width)
            rle = mask_utils.merge(rles)
            mask = mask_utils.decode(rle)
            mask = torch.from_numpy(mask)
            # TODO add squeeze?
            return mask

    def __repr__(self):
        s = self.__class__.__name__ + "("
        s += "num_polygons={}, ".format(len(self.polygons))
        s += "image_width={}, ".format(self.size[0])
        s += "image_height={}, ".format(self.size[1])
        s += "mode={})".format(self.mode)
        return s


class SegmentationMask(object):
    """

    This class stores the segmentations for all objects in the image

    """

    def __init__(self, polygons, size, mode=None):
        """

        Arguments:

            polygons: a list of list of lists of numbers. The first

                level of the list correspond to individual instances,

                the second level to all the polygons that compose the

                object, and the third level to the polygon coordinates.

        """
        assert isinstance(polygons, list)

        self.polygons = [Polygons(p, size, mode) for p in polygons]
        self.size = size
        self.mode = mode

    def transpose(self, method):
        if method not in (FLIP_LEFT_RIGHT, FLIP_TOP_BOTTOM):
            raise NotImplementedError("Only FLIP_LEFT_RIGHT and FLIP_TOP_BOTTOM implemented")

        flipped = []
        for polygon in self.polygons:
            flipped.append(polygon.transpose(method))
        return SegmentationMask(flipped, size=self.size, mode=self.mode)

    def crop(self, box):
        w, h = box[2] - box[0], box[3] - box[1]
        cropped = []
        for polygon in self.polygons:
            cropped.append(polygon.crop(box))
        return SegmentationMask(cropped, size=(w, h), mode=self.mode)

    def resize(self, size, *args, **kwargs):
        scaled = []
        for polygon in self.polygons:
            scaled.append(polygon.resize(size, *args, **kwargs))
        return SegmentationMask(scaled, size=size, mode=self.mode)

    def to(self, *args, **kwargs):
        return self

    def __getitem__(self, item):
        if isinstance(item, (int, slice)):
            selected_polygons = [self.polygons[item]]
        else:
            # advanced indexing on a single dimension
            selected_polygons = []
            if isinstance(item, torch.Tensor) and item.dtype == torch.bool:
                item = item.nonzero()
                item = item.squeeze(1) if item.numel() > 0 else item
                item = item.tolist()
            for i in item:
                selected_polygons.append(self.polygons[i])
        return SegmentationMask(selected_polygons, size=self.size, mode=self.mode)

    def __iter__(self):
        return iter(self.polygons)

    def __repr__(self):
        s = self.__class__.__name__ + "("
        s += "num_instances={}, ".format(len(self.polygons))
        s += "image_width={}, ".format(self.size[0])
        s += "image_height={})".format(self.size[1])
        return s