# %BANNER_BEGIN% # --------------------------------------------------------------------- # %COPYRIGHT_BEGIN% # # Magic Leap, Inc. ("COMPANY") CONFIDENTIAL # # Unpublished Copyright (c) 2020 # Magic Leap, Inc., All Rights Reserved. # # NOTICE: All information contained herein is, and remains the property # of COMPANY. The intellectual and technical concepts contained herein # are proprietary to COMPANY and may be covered by U.S. and Foreign # Patents, patents in process, and are protected by trade secret or # copyright law. Dissemination of this information or reproduction of # this material is strictly forbidden unless prior written permission is # obtained from COMPANY. Access to the source code contained herein is # hereby forbidden to anyone except current COMPANY employees, managers # or contractors who have executed Confidentiality and Non-disclosure # agreements explicitly covering such access. # # The copyright notice above does not evidence any actual or intended # publication or disclosure of this source code, which includes # information that is confidential and/or proprietary, and is a trade # secret, of COMPANY. ANY REPRODUCTION, MODIFICATION, DISTRIBUTION, # PUBLIC PERFORMANCE, OR PUBLIC DISPLAY OF OR THROUGH USE OF THIS # SOURCE CODE WITHOUT THE EXPRESS WRITTEN CONSENT OF COMPANY IS # STRICTLY PROHIBITED, AND IN VIOLATION OF APPLICABLE LAWS AND # INTERNATIONAL TREATIES. THE RECEIPT OR POSSESSION OF THIS SOURCE # CODE AND/OR RELATED INFORMATION DOES NOT CONVEY OR IMPLY ANY RIGHTS # TO REPRODUCE, DISCLOSE OR DISTRIBUTE ITS CONTENTS, OR TO MANUFACTURE, # USE, OR SELL ANYTHING THAT IT MAY DESCRIBE, IN WHOLE OR IN PART. # # %COPYRIGHT_END% # ---------------------------------------------------------------------- # %AUTHORS_BEGIN% # # Originating Authors: Paul-Edouard Sarlin # # %AUTHORS_END% # --------------------------------------------------------------------*/ # %BANNER_END% # Adapted by Remi Pautrat, Philipp Lindenberger import torch from torch import nn from .utils import ImagePreprocessor def simple_nms(scores, nms_radius: int): """Fast Non-maximum suppression to remove nearby points""" assert nms_radius >= 0 def max_pool(x): return torch.nn.functional.max_pool2d( x, kernel_size=nms_radius * 2 + 1, stride=1, padding=nms_radius ) zeros = torch.zeros_like(scores) max_mask = scores == max_pool(scores) for _ in range(2): supp_mask = max_pool(max_mask.float()) > 0 supp_scores = torch.where(supp_mask, zeros, scores) new_max_mask = supp_scores == max_pool(supp_scores) max_mask = max_mask | (new_max_mask & (~supp_mask)) return torch.where(max_mask, scores, zeros) def top_k_keypoints(keypoints, scores, k): if k >= len(keypoints): return keypoints, scores scores, indices = torch.topk(scores, k, dim=0, sorted=True) return keypoints[indices], scores def sample_descriptors(keypoints, descriptors, s: int = 8): """Interpolate descriptors at keypoint locations""" b, c, h, w = descriptors.shape keypoints = keypoints - s / 2 + 0.5 keypoints /= torch.tensor([(w * s - s / 2 - 0.5), (h * s - s / 2 - 0.5)],).to( keypoints )[None] keypoints = keypoints * 2 - 1 # normalize to (-1, 1) args = {"align_corners": True} if torch.__version__ >= "1.3" else {} descriptors = torch.nn.functional.grid_sample( descriptors, keypoints.view(b, 1, -1, 2), mode="bilinear", **args ) descriptors = torch.nn.functional.normalize( descriptors.reshape(b, c, -1), p=2, dim=1 ) return descriptors class SuperPoint(nn.Module): """SuperPoint Convolutional Detector and Descriptor SuperPoint: Self-Supervised Interest Point Detection and Description. Daniel DeTone, Tomasz Malisiewicz, and Andrew Rabinovich. In CVPRW, 2019. https://arxiv.org/abs/1712.07629 """ default_conf = { "descriptor_dim": 256, "nms_radius": 4, "max_num_keypoints": None, "detection_threshold": 0.0005, "remove_borders": 4, } preprocess_conf = { **ImagePreprocessor.default_conf, "resize": 1024, "grayscale": True, } required_data_keys = ["image"] def __init__(self, **conf): super().__init__() self.conf = {**self.default_conf, **conf} self.relu = nn.ReLU(inplace=True) self.pool = nn.MaxPool2d(kernel_size=2, stride=2) c1, c2, c3, c4, c5 = 64, 64, 128, 128, 256 self.conv1a = nn.Conv2d(1, c1, kernel_size=3, stride=1, padding=1) self.conv1b = nn.Conv2d(c1, c1, kernel_size=3, stride=1, padding=1) self.conv2a = nn.Conv2d(c1, c2, kernel_size=3, stride=1, padding=1) self.conv2b = nn.Conv2d(c2, c2, kernel_size=3, stride=1, padding=1) self.conv3a = nn.Conv2d(c2, c3, kernel_size=3, stride=1, padding=1) self.conv3b = nn.Conv2d(c3, c3, kernel_size=3, stride=1, padding=1) self.conv4a = nn.Conv2d(c3, c4, kernel_size=3, stride=1, padding=1) self.conv4b = nn.Conv2d(c4, c4, kernel_size=3, stride=1, padding=1) self.convPa = nn.Conv2d(c4, c5, kernel_size=3, stride=1, padding=1) self.convPb = nn.Conv2d(c5, 65, kernel_size=1, stride=1, padding=0) self.convDa = nn.Conv2d(c4, c5, kernel_size=3, stride=1, padding=1) self.convDb = nn.Conv2d( c5, self.conf["descriptor_dim"], kernel_size=1, stride=1, padding=0 ) url = "https://github.com/cvg/LightGlue/releases/download/v0.1_arxiv/superpoint_v1.pth" self.load_state_dict(torch.hub.load_state_dict_from_url(url)) mk = self.conf["max_num_keypoints"] if mk is not None and mk <= 0: raise ValueError("max_num_keypoints must be positive or None") print("Loaded SuperPoint model") def forward(self, data: dict) -> dict: """Compute keypoints, scores, descriptors for image""" for key in self.required_data_keys: assert key in data, f"Missing key {key} in data" image = data["image"] if image.shape[1] == 3: # RGB scale = image.new_tensor([0.299, 0.587, 0.114]).view(1, 3, 1, 1) image = (image * scale).sum(1, keepdim=True) # Shared Encoder x = self.relu(self.conv1a(image)) x = self.relu(self.conv1b(x)) x = self.pool(x) x = self.relu(self.conv2a(x)) x = self.relu(self.conv2b(x)) x = self.pool(x) x = self.relu(self.conv3a(x)) x = self.relu(self.conv3b(x)) x = self.pool(x) x = self.relu(self.conv4a(x)) x = self.relu(self.conv4b(x)) # Compute the dense keypoint scores cPa = self.relu(self.convPa(x)) scores = self.convPb(cPa) scores = torch.nn.functional.softmax(scores, 1)[:, :-1] b, _, h, w = scores.shape scores = scores.permute(0, 2, 3, 1).reshape(b, h, w, 8, 8) scores = scores.permute(0, 1, 3, 2, 4).reshape(b, h * 8, w * 8) scores = simple_nms(scores, self.conf["nms_radius"]) # Discard keypoints near the image borders if self.conf["remove_borders"]: pad = self.conf["remove_borders"] scores[:, :pad] = -1 scores[:, :, :pad] = -1 scores[:, -pad:] = -1 scores[:, :, -pad:] = -1 # Extract keypoints best_kp = torch.where(scores > self.conf["detection_threshold"]) scores = scores[best_kp] # Separate into batches keypoints = [ torch.stack(best_kp[1:3], dim=-1)[best_kp[0] == i] for i in range(b) ] scores = [scores[best_kp[0] == i] for i in range(b)] # Keep the k keypoints with highest score if self.conf["max_num_keypoints"] is not None: keypoints, scores = list( zip( *[ top_k_keypoints(k, s, self.conf["max_num_keypoints"]) for k, s in zip(keypoints, scores) ] ) ) # Convert (h, w) to (x, y) keypoints = [torch.flip(k, [1]).float() for k in keypoints] # Compute the dense descriptors cDa = self.relu(self.convDa(x)) descriptors = self.convDb(cDa) descriptors = torch.nn.functional.normalize(descriptors, p=2, dim=1) # Extract descriptors descriptors = [ sample_descriptors(k[None], d[None], 8)[0] for k, d in zip(keypoints, descriptors) ] return { "keypoints": torch.stack(keypoints, 0), "keypoint_scores": torch.stack(scores, 0), "descriptors": torch.stack(descriptors, 0).transpose(-1, -2), } def extract(self, img: torch.Tensor, **conf) -> dict: """Perform extraction with online resizing""" if img.dim() == 3: img = img[None] # add batch dim assert img.dim() == 4 and img.shape[0] == 1 shape = img.shape[-2:][::-1] img, scales = ImagePreprocessor(**{**self.preprocess_conf, **conf})(img) feats = self.forward({"image": img}) feats["image_size"] = torch.tensor(shape)[None].to(img).float() feats["keypoints"] = (feats["keypoints"] + 0.5) / scales[None] - 0.5 return feats