You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
91 lines
3.2 KiB
91 lines
3.2 KiB
""" A dataset parser that reads images from folders
|
|
|
|
Folders are scannerd recursively to find image files. Labels are based
|
|
on the folder hierarchy, just leaf folders by default.
|
|
|
|
Hacked together by / Copyright 2020 Ross Wightman
|
|
"""
|
|
import os
|
|
from typing import Dict, List, Optional, Set, Tuple, Union
|
|
|
|
from timm.utils.misc import natural_key
|
|
|
|
from .class_map import load_class_map
|
|
from .img_extensions import get_img_extensions
|
|
from .parser import Parser
|
|
|
|
|
|
def find_images_and_targets(
|
|
folder: str,
|
|
types: Optional[Union[List, Tuple, Set]] = None,
|
|
class_to_idx: Optional[Dict] = None,
|
|
leaf_name_only: bool = True,
|
|
sort: bool = True
|
|
):
|
|
""" Walk folder recursively to discover images and map them to classes by folder names.
|
|
|
|
Args:
|
|
folder: root of folder to recrusively search
|
|
types: types (file extensions) to search for in path
|
|
class_to_idx: specify mapping for class (folder name) to class index if set
|
|
leaf_name_only: use only leaf-name of folder walk for class names
|
|
sort: re-sort found images by name (for consistent ordering)
|
|
|
|
Returns:
|
|
A list of image and target tuples, class_to_idx mapping
|
|
"""
|
|
types = get_img_extensions(as_set=True) if not types else set(types)
|
|
labels = []
|
|
filenames = []
|
|
for root, subdirs, files in os.walk(folder, topdown=False, followlinks=True):
|
|
rel_path = os.path.relpath(root, folder) if (root != folder) else ''
|
|
label = os.path.basename(rel_path) if leaf_name_only else rel_path.replace(os.path.sep, '_')
|
|
for f in files:
|
|
base, ext = os.path.splitext(f)
|
|
if ext.lower() in types:
|
|
filenames.append(os.path.join(root, f))
|
|
labels.append(label)
|
|
if class_to_idx is None:
|
|
# building class index
|
|
unique_labels = set(labels)
|
|
sorted_labels = list(sorted(unique_labels, key=natural_key))
|
|
class_to_idx = {c: idx for idx, c in enumerate(sorted_labels)}
|
|
images_and_targets = [(f, class_to_idx[l]) for f, l in zip(filenames, labels) if l in class_to_idx]
|
|
if sort:
|
|
images_and_targets = sorted(images_and_targets, key=lambda k: natural_key(k[0]))
|
|
return images_and_targets, class_to_idx
|
|
|
|
|
|
class ParserImageFolder(Parser):
|
|
|
|
def __init__(
|
|
self,
|
|
root,
|
|
class_map=''):
|
|
super().__init__()
|
|
|
|
self.root = root
|
|
class_to_idx = None
|
|
if class_map:
|
|
class_to_idx = load_class_map(class_map, root)
|
|
self.samples, self.class_to_idx = find_images_and_targets(root, class_to_idx=class_to_idx)
|
|
if len(self.samples) == 0:
|
|
raise RuntimeError(
|
|
f'Found 0 images in subfolders of {root}. '
|
|
f'Supported image extensions are {", ".join(get_img_extensions())}')
|
|
|
|
def __getitem__(self, index):
|
|
path, target = self.samples[index]
|
|
return open(path, 'rb'), target
|
|
|
|
def __len__(self):
|
|
return len(self.samples)
|
|
|
|
def _filename(self, index, basename=False, absolute=False):
|
|
filename = self.samples[index][0]
|
|
if basename:
|
|
filename = os.path.basename(filename)
|
|
elif not absolute:
|
|
filename = os.path.relpath(filename, self.root)
|
|
return filename
|