File size: 9,106 Bytes
1b369eb
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
# Description: RDD model
import torch
import torch.nn.functional as F
from torch import nn
import numpy as np
from .utils import NestedTensor, nested_tensor_from_tensor_list, to_pixel_coords, read_config
from .models.detector import build_detector
from .models.descriptor import build_descriptor
from .models.soft_detect import SoftDetect
from .models.interpolator import InterpolateSparse2d

class RDD(nn.Module):

    def __init__(self, detector, descriptor, detection_threshold=0.5, top_k=4096, train_detector=False, device='cuda'):
        super().__init__()
        self.detector = detector
        self.descriptor = descriptor
        self.interpolator = InterpolateSparse2d('bicubic')
        self.detection_threshold = detection_threshold
        self.top_k = top_k
        self.device = device
        if train_detector:
            for p in self.detector.parameters():
                p.requires_grad = True
            for p in self.descriptor.parameters():
                p.requires_grad = False
        else:
            for p in self.detector.parameters():
                p.requires_grad = False
            for p in self.descriptor.parameters():
                p.requires_grad = True
        
        self.softdetect = None
        self.stride = descriptor.stride

    def train(self, mode=True):
        super().train(mode)
        self.set_softdetect(top_k=500, scores_th=0.2)
        
    def eval(self):
        super().eval()
        self.set_softdetect(top_k=self.top_k, scores_th=0.01)
        
    def forward(self, samples: NestedTensor):
        
        if not isinstance(samples, NestedTensor):
            samples = nested_tensor_from_tensor_list(samples)
        
        scoremap = self.detector(samples)
        
        feats, matchibility = self.descriptor(samples)
        
        return feats, scoremap, matchibility
    
    def set_softdetect(self, top_k=4096, scores_th=0.01):
        self.softdetect = SoftDetect(radius=2, top_k=top_k, scores_th=scores_th)
    
    @torch.inference_mode()
    def filter(self, matchibility):
        # Filter out keypoints on the border
        B, _, H, W = matchibility.shape
        frame = torch.zeros(B, H, W, device=matchibility.device)
        frame[:, self.stride:-self.stride, self.stride:-self.stride] = 1
        matchibility = matchibility * frame
        return matchibility
    
    @torch.inference_mode()
    def extract(self, x):
        if self.softdetect is None:
            self.eval()
        
        x, rh1, rw1 = self.preprocess_tensor(x)
        x = x.to(self.device).float()
        B, _, _H1, _W1 = x.shape
        M1, K1, H1 = self.forward(x)
        M1 = F.normalize(M1, dim=1)
        
        keypoints, kptscores, scoredispersitys = self.softdetect(K1)
        
        keypoints = torch.vstack([keypoints[b].unsqueeze(0) for b in range(B)])
        kptscores = torch.vstack([kptscores[b].unsqueeze(0) for b in range(B)])
        
        keypoints = to_pixel_coords(keypoints, _H1, _W1)
        
        feats = self.interpolator(M1, keypoints, H = _H1, W = _W1)
        
        feats = F.normalize(feats, dim=-1)
		
        # Correct kpt scale
        keypoints = keypoints * torch.tensor([rw1,rh1], device=keypoints.device).view(1, -1)
        valid = kptscores > self.detection_threshold

        return [  
                    {'keypoints': keypoints[b][valid[b]],
                    'scores': kptscores[b][valid[b]],
                    'descriptors': feats[b][valid[b]]} for b in range(B) 
                ]	
        
    @torch.inference_mode()
    def extract_3rd_party(self, x, model='aliked'):
        """
        one image per batch
        """
        x, rh1, rw1 = self.preprocess_tensor(x)
        B, _, _H1, _W1 = x.shape
        if model == 'aliked':
            from third_party import extract_aliked_kpts
            img = x
            mkpts, scores = extract_aliked_kpts(img, self.device)
        else:
            raise ValueError('Unknown model')
    
        M1, _ = self.descriptor(x)
        M1 = F.normalize(M1, dim=1)
        
        if mkpts.shape[1] > self.top_k:
            idx = torch.argsort(scores, descending=True)[0][:self.top_k]
            mkpts = mkpts[:,idx]
            scores = scores[:,idx]

        feats = self.interpolator(M1, mkpts, H = _H1, W = _W1)
        feats = F.normalize(feats, dim=-1)
        mkpts = mkpts * torch.tensor([rw1,rh1], device=mkpts.device).view(1, 1, -1)
        
        return [  
				   {'keypoints': mkpts[b],
                    'scores': scores[b],
					'descriptors': feats[b]} for b in range(B) 
			   ]
        
    @torch.inference_mode()
    def extract_dense(self, x, n_limit=30000, thr=0.01):
        self.set_softdetect(top_k=n_limit, scores_th=-1)
            
        x, rh1, rw1 = self.preprocess_tensor(x)

        B, _, _H1, _W1 = x.shape

        M1, K1, H1 = self.forward(x)
        M1 = F.normalize(M1, dim=1)
        
        keypoints, kptscores, scoredispersitys = self.softdetect(K1)
        
        keypoints = torch.vstack([keypoints[b].unsqueeze(0) for b in range(B)])
        kptscores = torch.vstack([kptscores[b].unsqueeze(0) for b in range(B)])
        
        keypoints = to_pixel_coords(keypoints, _H1, _W1)
        
        feats = self.interpolator(M1, keypoints, H = _H1, W = _W1)
        
        feats = F.normalize(feats, dim=-1)
        
        H1 = self.filter(H1)
        
        dense_kpts, dense_scores, inds = self.sample_dense_kpts(H1, n_limit=n_limit)
 
        dense_keypoints = to_pixel_coords(dense_kpts, _H1, _W1)

        dense_feats = self.interpolator(M1, dense_keypoints, H = _H1, W = _W1)
        
        dense_feats = F.normalize(dense_feats, dim=-1)
        
        keypoints = keypoints * torch.tensor([rw1,rh1], device=keypoints.device).view(1, -1)
        dense_keypoints = dense_keypoints * torch.tensor([rw1,rh1], device=dense_keypoints.device).view(1, -1)	

        valid = kptscores > self.detection_threshold
        valid_dense = dense_scores > thr		

        return [  
                    {'keypoints': keypoints[b][valid[b]],
                    'scores': kptscores[b][valid[b]],
                    'descriptors': feats[b][valid[b]], 
                    'keypoints_dense': dense_keypoints[b][valid_dense[b]],
                    'scores_dense': dense_scores[b][valid_dense[b]],
                    'descriptors_dense': dense_feats[b][valid_dense[b]]} for b in range(B)
                ]
        
    @torch.inference_mode()
    def sample_dense_kpts(self, keypoint_logits, threshold=0.01, n_limit=30000, force_kpts = True):
        
        B, K, H, W = keypoint_logits.shape

        if n_limit < 0 or n_limit > H*W:
            n_limit = min(H*W - 1, n_limit)

        scoremap = keypoint_logits.permute(0,2,3,1)

        scoremap = scoremap.reshape(B, H, W)

        frame = torch.zeros(B, H, W, device=keypoint_logits.device)

        frame[:, 1:-1, 1:-1] = 1

        scoremap = scoremap * frame

        scoremap = scoremap.reshape(B, H*W)

        grid = self.get_grid(B, H, W, device = keypoint_logits.device)

        inds = torch.topk(scoremap, n_limit, dim=1).indices

        # inds = torch.multinomial(scoremap, top_k, replacement=False)
        kpts = torch.gather(grid, 1, inds[..., None].expand(B, n_limit, 2))
        scoremap = torch.gather(scoremap, 1, inds)
        if force_kpts:
            valid = scoremap > threshold
            kpts = kpts[valid][None]
            scoremap = scoremap[valid][None]

        return kpts, scoremap, inds

    def preprocess_tensor(self, x):
        """ Guarantee that image is divisible by 32 to avoid aliasing artifacts. """
        if isinstance(x, np.ndarray) and len(x.shape) == 3:
            x = torch.tensor(x).permute(2,0,1)[None]
        x = x.to(self.device).float()

        H, W = x.shape[-2:]

        _H, _W = (H//32) * 32, (W//32) * 32

        rh, rw = H/_H, W/_W

        x = F.interpolate(x, (_H, _W), mode='bilinear', align_corners=False)
        return x, rh, rw

    @torch.inference_mode()
    def get_grid(self, B, H, W, device = None):
        x1_n = torch.meshgrid(
        *[
            torch.linspace(
                -1 + 1 / n, 1 - 1 / n, n, device=device
            )
            for n in (B, H, W)
        ]
        )
        x1_n = torch.stack((x1_n[2], x1_n[1]), dim=-1).reshape(B, H * W, 2)
        return x1_n

def build(config=None, weights=None):
    if config is None:
        config = read_config('./configs/default.yaml')
    if weights is not None:
        config['weights'] = weights
    device = torch.device(config['device'])
    print('config', config)
    detector = build_detector(config)
    descriptor = build_descriptor(config)
    model = RDD(
        detector, 
        descriptor, 
        detection_threshold=config['detection_threshold'], 
        top_k=config['top_k'], 
        train_detector=config['train_detector'],
        device=device
    )
    if 'weights' in config and config['weights'] is not None:
        model.load_state_dict(torch.load(config['weights'], map_location='cpu'))
    model.to(device)
    return model