hytian2@gmail.com
update
2b34e02
import logging
import glob
from tqdm import tqdm
import numpy as np
import torch
import cv2
class FaceDetector(object):
"""An abstract class representing a face detector.
Any other face detection implementation must subclass it. All subclasses
must implement ``detect_from_image``, that return a list of detected
bounding boxes. Optionally, for speed considerations detect from path is
recommended.
"""
def __init__(self, device, verbose):
self.device = device
self.verbose = verbose
if verbose:
if 'cpu' in device:
logger = logging.getLogger(__name__)
logger.warning("Detection running on CPU, this may be potentially slow.")
if 'cpu' not in device and 'cuda' not in device:
if verbose:
logger.error("Expected values for device are: {cpu, cuda} but got: %s", device)
raise ValueError
def detect_from_image(self, tensor_or_path):
"""Detects faces in a given image.
This function detects the faces present in a provided BGR(usually)
image. The input can be either the image itself or the path to it.
Arguments:
tensor_or_path {numpy.ndarray, torch.tensor or string} -- the path
to an image or the image itself.
Example::
>>> path_to_image = 'data/image_01.jpg'
... detected_faces = detect_from_image(path_to_image)
[A list of bounding boxes (x1, y1, x2, y2)]
>>> image = cv2.imread(path_to_image)
... detected_faces = detect_from_image(image)
[A list of bounding boxes (x1, y1, x2, y2)]
"""
raise NotImplementedError
def detect_from_directory(self, path, extensions=['.jpg', '.png'], recursive=False, show_progress_bar=True):
"""Detects faces from all the images present in a given directory.
Arguments:
path {string} -- a string containing a path that points to the folder containing the images
Keyword Arguments:
extensions {list} -- list of string containing the extensions to be
consider in the following format: ``.extension_name`` (default:
{['.jpg', '.png']}) recursive {bool} -- option wherever to scan the
folder recursively (default: {False}) show_progress_bar {bool} --
display a progressbar (default: {True})
Example:
>>> directory = 'data'
... detected_faces = detect_from_directory(directory)
{A dictionary of [lists containing bounding boxes(x1, y1, x2, y2)]}
"""
if self.verbose:
logger = logging.getLogger(__name__)
if len(extensions) == 0:
if self.verbose:
logger.error("Expected at list one extension, but none was received.")
raise ValueError
if self.verbose:
logger.info("Constructing the list of images.")
additional_pattern = '/**/*' if recursive else '/*'
files = []
for extension in extensions:
files.extend(glob.glob(path + additional_pattern + extension, recursive=recursive))
if self.verbose:
logger.info("Finished searching for images. %s images found", len(files))
logger.info("Preparing to run the detection.")
predictions = {}
for image_path in tqdm(files, disable=not show_progress_bar):
if self.verbose:
logger.info("Running the face detector on image: %s", image_path)
predictions[image_path] = self.detect_from_image(image_path)
if self.verbose:
logger.info("The detector was successfully run on all %s images", len(files))
return predictions
@property
def reference_scale(self):
raise NotImplementedError
@property
def reference_x_shift(self):
raise NotImplementedError
@property
def reference_y_shift(self):
raise NotImplementedError
@staticmethod
def tensor_or_path_to_ndarray(tensor_or_path, rgb=True):
"""Convert path (represented as a string) or torch.tensor to a numpy.ndarray
Arguments:
tensor_or_path {numpy.ndarray, torch.tensor or string} -- path to the image, or the image itself
"""
if isinstance(tensor_or_path, str):
return cv2.imread(tensor_or_path) if not rgb else cv2.imread(tensor_or_path)[..., ::-1]
elif torch.is_tensor(tensor_or_path):
# Call cpu in case its coming from cuda
return tensor_or_path.cpu().numpy()[..., ::-1].copy() if not rgb else tensor_or_path.cpu().numpy()
elif isinstance(tensor_or_path, np.ndarray):
return tensor_or_path[..., ::-1].copy() if not rgb else tensor_or_path
else:
raise TypeError