Source code for torchvision.datasets.phototour
import os
import numpy as np
from PIL import Image
from typing import Any, Callable, List, Optional, Tuple, Union
import torch
from .vision import VisionDataset
from .utils import download_url
[docs]class PhotoTour(VisionDataset):
"""`Multi-view Stereo Correspondence <http://matthewalunbrown.com/patchdata/patchdata.html>`_ Dataset.
.. note::
We only provide the newer version of the dataset, since the authors state that it
is more suitable for training descriptors based on difference of Gaussian, or Harris corners, as the
patches are centred on real interest point detections, rather than being projections of 3D points as is the
case in the old dataset.
The original dataset is available under http://phototour.cs.washington.edu/patches/default.htm.
Args:
root (string): Root directory where images are.
name (string): Name of the dataset to load.
transform (callable, optional): A function/transform that takes in an PIL image
and returns a transformed version.
download (bool, optional): If true, downloads the dataset from the internet and
puts it in root directory. If dataset is already downloaded, it is not
downloaded again.
"""
urls = {
'notredame_harris': [
'http://matthewalunbrown.com/patchdata/notredame_harris.zip',
'notredame_harris.zip',
'69f8c90f78e171349abdf0307afefe4d'
],
'yosemite_harris': [
'http://matthewalunbrown.com/patchdata/yosemite_harris.zip',
'yosemite_harris.zip',
'a73253d1c6fbd3ba2613c45065c00d46'
],
'liberty_harris': [
'http://matthewalunbrown.com/patchdata/liberty_harris.zip',
'liberty_harris.zip',
'c731fcfb3abb4091110d0ae8c7ba182c'
],
'notredame': [
'http://icvl.ee.ic.ac.uk/vbalnt/notredame.zip',
'notredame.zip',
'509eda8535847b8c0a90bbb210c83484'
],
'yosemite': [
'http://icvl.ee.ic.ac.uk/vbalnt/yosemite.zip',
'yosemite.zip',
'533b2e8eb7ede31be40abc317b2fd4f0'
],
'liberty': [
'http://icvl.ee.ic.ac.uk/vbalnt/liberty.zip',
'liberty.zip',
'fdd9152f138ea5ef2091746689176414'
],
}
means = {'notredame': 0.4854, 'yosemite': 0.4844, 'liberty': 0.4437,
'notredame_harris': 0.4854, 'yosemite_harris': 0.4844, 'liberty_harris': 0.4437}
stds = {'notredame': 0.1864, 'yosemite': 0.1818, 'liberty': 0.2019,
'notredame_harris': 0.1864, 'yosemite_harris': 0.1818, 'liberty_harris': 0.2019}
lens = {'notredame': 468159, 'yosemite': 633587, 'liberty': 450092,
'liberty_harris': 379587, 'yosemite_harris': 450912, 'notredame_harris': 325295}
image_ext = 'bmp'
info_file = 'info.txt'
matches_files = 'm50_100000_100000_0.txt'
def __init__(
self, root: str, name: str, train: bool = True, transform: Optional[Callable] = None, download: bool = False
) -> None:
super(PhotoTour, self).__init__(root, transform=transform)
self.name = name
self.data_dir = os.path.join(self.root, name)
self.data_down = os.path.join(self.root, '{}.zip'.format(name))
self.data_file = os.path.join(self.root, '{}.pt'.format(name))
self.train = train
self.mean = self.means[name]
self.std = self.stds[name]
if download:
self.download()
if not self._check_datafile_exists():
self.cache()
# load the serialized data
self.data, self.labels, self.matches = torch.load(self.data_file)
[docs] def __getitem__(self, index: int) -> Union[torch.Tensor, Tuple[Any, Any, torch.Tensor]]:
"""
Args:
index (int): Index
Returns:
tuple: (data1, data2, matches)
"""
if self.train:
data = self.data[index]
if self.transform is not None:
data = self.transform(data)
return data
m = self.matches[index]
data1, data2 = self.data[m[0]], self.data[m[1]]
if self.transform is not None:
data1 = self.transform(data1)
data2 = self.transform(data2)
return data1, data2, m[2]
def __len__(self) -> int:
return len(self.data if self.train else self.matches)
def _check_datafile_exists(self) -> bool:
return os.path.exists(self.data_file)
def _check_downloaded(self) -> bool:
return os.path.exists(self.data_dir)
def download(self) -> None:
if self._check_datafile_exists():
print('# Found cached data {}'.format(self.data_file))
return
if not self._check_downloaded():
# download files
url = self.urls[self.name][0]
filename = self.urls[self.name][1]
md5 = self.urls[self.name][2]
fpath = os.path.join(self.root, filename)
download_url(url, self.root, filename, md5)
print('# Extracting data {}\n'.format(self.data_down))
import zipfile
with zipfile.ZipFile(fpath, 'r') as z:
z.extractall(self.data_dir)
os.unlink(fpath)
def cache(self) -> None:
# process and save as torch files
print('# Caching data {}'.format(self.data_file))
dataset = (
read_image_file(self.data_dir, self.image_ext, self.lens[self.name]),
read_info_file(self.data_dir, self.info_file),
read_matches_files(self.data_dir, self.matches_files)
)
with open(self.data_file, 'wb') as f:
torch.save(dataset, f)
def extra_repr(self) -> str:
return "Split: {}".format("Train" if self.train is True else "Test")
def read_image_file(data_dir: str, image_ext: str, n: int) -> torch.Tensor:
"""Return a Tensor containing the patches
"""
def PIL2array(_img: Image.Image) -> np.ndarray:
"""Convert PIL image type to numpy 2D array
"""
return np.array(_img.getdata(), dtype=np.uint8).reshape(64, 64)
def find_files(_data_dir: str, _image_ext: str) -> List[str]:
"""Return a list with the file names of the images containing the patches
"""
files = []
# find those files with the specified extension
for file_dir in os.listdir(_data_dir):
if file_dir.endswith(_image_ext):
files.append(os.path.join(_data_dir, file_dir))
return sorted(files) # sort files in ascend order to keep relations
patches = []
list_files = find_files(data_dir, image_ext)
for fpath in list_files:
img = Image.open(fpath)
for y in range(0, img.height, 64):
for x in range(0, img.width, 64):
patch = img.crop((x, y, x + 64, y + 64))
patches.append(PIL2array(patch))
return torch.ByteTensor(np.array(patches[:n]))
def read_info_file(data_dir: str, info_file: str) -> torch.Tensor:
"""Return a Tensor containing the list of labels
Read the file and keep only the ID of the 3D point.
"""
with open(os.path.join(data_dir, info_file), 'r') as f:
labels = [int(line.split()[0]) for line in f]
return torch.LongTensor(labels)
def read_matches_files(data_dir: str, matches_file: str) -> torch.Tensor:
"""Return a Tensor containing the ground truth matches
Read the file and keep only 3D point ID.
Matches are represented with a 1, non matches with a 0.
"""
matches = []
with open(os.path.join(data_dir, matches_file), 'r') as f:
for line in f:
line_split = line.split()
matches.append([int(line_split[0]), int(line_split[3]),
int(line_split[1] == line_split[4])])
return torch.LongTensor(matches)
