""" Copyright 2017-2018 Fizyr (https://fizyr.com) Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. """ from .anchors import compute_overlap from .visualization import draw_detections, draw_annotations import keras import numpy as np import os import time import cv2 import progressbar assert(callable(progressbar.progressbar)), "Using wrong progressbar module, install 'progressbar2' instead." def _compute_ap(recall, precision): """ Compute the average precision, given the recall and precision curves. Code originally from https://github.com/rbgirshick/py-faster-rcnn. # Arguments recall: The recall curve (list). precision: The precision curve (list). # Returns The average precision as computed in py-faster-rcnn. """ # correct AP calculation # first append sentinel values at the end mrec = np.concatenate(([0.], recall, [1.])) mpre = np.concatenate(([0.], precision, [0.])) # compute the precision envelope for i in range(mpre.size - 1, 0, -1): mpre[i - 1] = np.maximum(mpre[i - 1], mpre[i]) # to calculate area under PR curve, look for points # where X axis (recall) changes value i = np.where(mrec[1:] != mrec[:-1])[0] # and sum (\Delta recall) * prec ap = np.sum((mrec[i + 1] - mrec[i]) * mpre[i + 1]) return ap def _get_detections(generator, model, score_threshold=0.05, max_detections=100, save_path=None): """ Get the detections from the model using the generator. The result is a list of lists such that the size is: all_detections[num_images][num_classes] = detections[num_detections, 4 + num_classes] # Arguments generator : The generator used to run images through the model. model : The model to run on the images. score_threshold : The score confidence threshold to use. max_detections : The maximum number of detections to use per image. save_path : The path to save the images with visualized detections to. # Returns A list of lists containing the detections for each image in the generator. """ all_detections = [[None for i in range(generator.num_classes()) if generator.has_label(i)] for j in range(generator.size())] all_inferences = [None for i in range(generator.size())] for i in progressbar.progressbar(range(generator.size()), prefix='Running network: '): raw_image = generator.load_image(i) image = generator.preprocess_image(raw_image.copy()) image, scale = generator.resize_image(image) if keras.backend.image_data_format() == 'channels_first': image = image.transpose((2, 0, 1)) # run network start = time.time() boxes, scores, labels = model.predict_on_batch(np.expand_dims(image, axis=0))[:3] inference_time = time.time() - start # correct boxes for image scale boxes /= scale # select indices which have a score above the threshold indices = np.where(scores[0, :] > score_threshold)[0] # select those scores scores = scores[0][indices] # find the order with which to sort the scores scores_sort = np.argsort(-scores)[:max_detections] # select detections image_boxes = boxes[0, indices[scores_sort], :] image_scores = scores[scores_sort] image_labels = labels[0, indices[scores_sort]] image_detections = np.concatenate([image_boxes, np.expand_dims(image_scores, axis=1), np.expand_dims(image_labels, axis=1)], axis=1) if save_path is not None: draw_annotations(raw_image, generator.load_annotations(i), label_to_name=generator.label_to_name) draw_detections(raw_image, image_boxes, image_scores, image_labels, label_to_name=generator.label_to_name, score_threshold=score_threshold) cv2.imwrite(os.path.join(save_path, '{}.png'.format(i)), raw_image) # copy detections to all_detections for label in range(generator.num_classes()): if not generator.has_label(label): continue all_detections[i][label] = image_detections[image_detections[:, -1] == label, :-1] all_inferences[i] = inference_time return all_detections, all_inferences def _get_annotations(generator): """ Get the ground truth annotations from the generator. The result is a list of lists such that the size is: all_detections[num_images][num_classes] = annotations[num_detections, 5] # Arguments generator : The generator used to retrieve ground truth annotations. # Returns A list of lists containing the annotations for each image in the generator. """ all_annotations = [[None for i in range(generator.num_classes())] for j in range(generator.size())] for i in progressbar.progressbar(range(generator.size()), prefix='Parsing annotations: '): # load the annotations annotations = generator.load_annotations(i) # copy detections to all_annotations for label in range(generator.num_classes()): if not generator.has_label(label): continue all_annotations[i][label] = annotations['bboxes'][annotations['labels'] == label, :].copy() return all_annotations def evaluate( generator, model, iou_threshold=0.5, score_threshold=0.05, max_detections=100, save_path=None ): """ Evaluate a given dataset using a given model. # Arguments generator : The generator that represents the dataset to evaluate. model : The model to evaluate. iou_threshold : The threshold used to consider when a detection is positive or negative. score_threshold : The score confidence threshold to use for detections. max_detections : The maximum number of detections to use per image. save_path : The path to save images with visualized detections to. # Returns A dict mapping class names to mAP scores. """ # gather all detections and annotations all_detections, all_inferences = _get_detections(generator, model, score_threshold=score_threshold, max_detections=max_detections, save_path=save_path) all_annotations = _get_annotations(generator) average_precisions = {} # all_detections = pickle.load(open('all_detections.pkl', 'rb')) # all_annotations = pickle.load(open('all_annotations.pkl', 'rb')) # pickle.dump(all_detections, open('all_detections.pkl', 'wb')) # pickle.dump(all_annotations, open('all_annotations.pkl', 'wb')) # process detections and annotations for label in range(generator.num_classes()): if not generator.has_label(label): continue false_positives = np.zeros((0,)) true_positives = np.zeros((0,)) scores = np.zeros((0,)) num_annotations = 0.0 for i in range(generator.size()): detections = all_detections[i][label] annotations = all_annotations[i][label] num_annotations += annotations.shape[0] detected_annotations = [] for d in detections: scores = np.append(scores, d[4]) if annotations.shape[0] == 0: false_positives = np.append(false_positives, 1) true_positives = np.append(true_positives, 0) continue overlaps = compute_overlap(np.expand_dims(d, axis=0), annotations) assigned_annotation = np.argmax(overlaps, axis=1) max_overlap = overlaps[0, assigned_annotation] if max_overlap >= iou_threshold and assigned_annotation not in detected_annotations: false_positives = np.append(false_positives, 0) true_positives = np.append(true_positives, 1) detected_annotations.append(assigned_annotation) else: false_positives = np.append(false_positives, 1) true_positives = np.append(true_positives, 0) # no annotations -> AP for this class is 0 (is this correct?) if num_annotations == 0: average_precisions[label] = 0, 0 continue # sort by score indices = np.argsort(-scores) false_positives = false_positives[indices] true_positives = true_positives[indices] # compute false positives and true positives false_positives = np.cumsum(false_positives) true_positives = np.cumsum(true_positives) # compute recall and precision recall = true_positives / num_annotations precision = true_positives / np.maximum(true_positives + false_positives, np.finfo(np.float64).eps) # compute average precision average_precision = _compute_ap(recall, precision) average_precisions[label] = average_precision, num_annotations # inference time inference_time = np.sum(all_inferences) / generator.size() return average_precisions, inference_time