• 目标检测之车辆行人(tensorflow版yolov3-tiny)


    背景:

           在自动驾驶中,基于摄像头的视觉感知,如同人的眼睛一样重要。而目前主流方案基本都采用深度学习方案(tensorflow等),而非传统图像处理(opencv等)。

      接下来我们就以YOLOV3为基本网络模型,Tensorflow为基本框架,搭建一套能够自动识别路面上动态目标,如车辆,行人,骑行人等。

    正文:

      原生YOLOV3是基于darknet(纯C编写)开发的,这里我们会将YOLOV3架构在Tensorflow平台上(Python,C++跨平台多语言)。

           关键点介绍:

           一、基本的网络结构图:

           

     

    模型流程图如下:

      基础主干网Darknet53:

    二、代码结构:

    tf_yolov3

    |-------extract_voc.py #从原始文件中生成训练所需数据格式

    import os
    import argparse
    import xml.etree.ElementTree as ET
    
    # sets=[('2007', 'train'), ('2007', 'val'), ('2007', 'test')]
    sets=[('2012', 'train'), ('2012', 'val')]
    
    classes = ["aeroplane", "bicycle", "bird", "boat", "bottle", "bus", "car", "cat", "chair", "cow", "diningtable", "dog", "horse", "motorbike", "person", "pottedplant", "sheep", "sofa", "train", "tvmonitor"]
    
    parser = argparse.ArgumentParser()
    parser.add_argument("--voc_path", default="/home/yang/test/VOCdevkit/train/")
    parser.add_argument("--dataset_info_path", default="./")
    flags = parser.parse_args()
    
    def convert_annotation(year, image_id, list_file):
        xml_path = os.path.join(flags.voc_path, 'VOCdevkit/VOC%s/Annotations/%s.xml'%(year, image_id))
        in_file = open(xml_path)
        tree=ET.parse(in_file)
        root = tree.getroot()
    
        for obj in root.iter('object'):
            difficult = obj.find('difficult').text
            cls = obj.find('name').text
            if cls not in classes or int(difficult)==1:
                continue
            cls_id = classes.index(cls)
            xmlbox = obj.find('bndbox')
            b = (int(xmlbox.find('xmin').text), int(xmlbox.find('ymin').text), int(xmlbox.find('xmax').text), int(xmlbox.find('ymax').text))
            list_file.write(" " +  " ".join([str(a) for a in b]) + " " + str(cls_id))
    
    
    for year, image_set in sets:
        text_path = os.path.join(flags.voc_path, 'VOCdevkit/VOC%s/ImageSets/Main/%s.txt'%(year, image_set))
        if not os.path.exists(text_path): continue
        image_ids = open(text_path).read().strip().split()
        list_file_path = os.path.join(flags.dataset_info_path, '%s_%s.txt'%(year, image_set))
        list_file = open(list_file_path, 'w')
        for image_id in image_ids:
            image_path = os.path.join(flags.voc_path, 'VOCdevkit/VOC%s/JPEGImages/%s.jpg'%(year, image_id))
            print("=>", image_path)
            list_file.write(image_path)
            convert_annotation(year, image_id, list_file)
            list_file.write('
    ')
        list_file.close()
    View Code

      |-------make_voc_tfrecord.sh  #制作tfrecord格式

    python scripts/extract_voc.py --voc_path /home/yang/test/VOC/train/ --dataset_info_path ./
    cat ./2007_train.txt ./2007_val.txt > voc_train.txt
    python scripts/extract_voc.py --voc_path /home/yang/test/VOC/test/ --dataset_info_path ./
    cat ./2007_test.txt > voc_test.txt
    python core/convert_tfrecord.py --dataset_txt ./voc_train.txt --tfrecord_path_prefix /home/yang/test/VOC/train/voc_train
    python core/convert_tfrecord.py --dataset_txt ./voc_test.txt  --tfrecord_path_prefix /home/yang/test/VOC/test/voc_test
    View Code

    |-------convert_tfrecord.py # 转换原始数据成TFReocord格式

    import sys
    import argparse
    import numpy as np
    import tensorflow as tf
    
    def main(argv):
        parser = argparse.ArgumentParser()
        parser.add_argument("--dataset_txt", default='./data/dataset.txt')
        parser.add_argument("--tfrecord_path_prefix", default='./data/tfrecords/dataset')
        flags = parser.parse_args()
    
        dataset = {}
        #
        with open(flags.dataset_txt,'r') as f:
            for line in f.readlines():
                example = line.split(' ')
                image_path = example[0]
                boxes_num = len(example[1:]) // 5
                boxes = np.zeros([boxes_num, 5], dtype=np.float32)
                for i in range(boxes_num):
                    boxes[i] = example[1+i*5:6+i*5]
                dataset[image_path] = boxes
    
        image_paths = list(dataset.keys())
        images_num = len(image_paths)
        print(">> Processing %d images" %images_num)
    
        tfrecord_file = flags.tfrecord_path_prefix+".tfrecords"
        with tf.python_io.TFRecordWriter(tfrecord_file) as record_writer:
            for i in range(images_num):
                image = tf.gfile.FastGFile(image_paths[i], 'rb').read()
                boxes = dataset[image_paths[i]]
                boxes = boxes.tostring()
    
                example = tf.train.Example(features = tf.train.Features(
                    feature={
                        'image' :tf.train.Feature(bytes_list = tf.train.BytesList(value = [image])),
                        'boxes' :tf.train.Feature(bytes_list = tf.train.BytesList(value = [boxes])),
                    }
                ))
    
                record_writer.write(example.SerializeToString())
            print(">> Saving %d images in %s" %(images_num, tfrecord_file))
    View Code

    |-------dataset.py # 图片数据增强,数据加载

    import cv2
    import numpy as np
    from core import utils
    import tensorflow as tf
    
    class Parser(object):
        def __init__(self, image_h, image_w, anchors, num_classes, debug=False):
    
            self.anchors     = anchors
            self.num_classes = num_classes
            self.image_h     = image_h
            self.image_w     = image_w
            self.debug       = debug
    
        def flip_left_right(self, image, gt_boxes):
    
            w = tf.cast(tf.shape(image)[1], tf.float32)
            image = tf.image.flip_left_right(image)
    
            xmin, ymin, xmax, ymax, label = tf.unstack(gt_boxes, axis=1)
            xmin, ymin, xmax, ymax = w-xmax, ymin, w-xmin, ymax
            gt_boxes = tf.stack([xmin, ymin, xmax, ymax, label], axis=1)
    
            return image, gt_boxes
    
        def random_distort_color(self, image, gt_boxes):
    
            image = tf.image.random_brightness(image, max_delta=32./255.)
            image = tf.image.random_saturation(image, lower=0.8, upper=1.2)
            image = tf.image.random_hue(image, max_delta=0.2)
            image = tf.image.random_contrast(image, lower=0.8, upper=1.2)
    
            return image, gt_boxes
    
        def random_blur(self, image, gt_boxes):
    
            gaussian_blur = lambda image: cv2.GaussianBlur(image, (5, 5), 0)
            h, w = image.shape.as_list()[:2]
            image = tf.py_func(gaussian_blur, [image], tf.uint8)
            image.set_shape([h, w, 3])
    
            return image, gt_boxes
    
        def random_crop(self, image, gt_boxes, min_object_covered=0.8, aspect_ratio_range=[0.8, 1.2], area_range=[0.5, 1.0]):
    
            h, w = tf.cast(tf.shape(image)[0], tf.float32), tf.cast(tf.shape(image)[1], tf.float32)
            xmin, ymin, xmax, ymax, label = tf.unstack(gt_boxes, axis=1)
            bboxes = tf.stack([ ymin/h, xmin/w, ymax/h, xmax/w], axis=1)
            bboxes = tf.clip_by_value(bboxes, 0, 1)
            begin, size, dist_boxes = tf.image.sample_distorted_bounding_box(
                                            tf.shape(image),
                                            bounding_boxes=tf.expand_dims(bboxes, axis=0),
                                            min_object_covered=min_object_covered,
                                            aspect_ratio_range=aspect_ratio_range,
                                            area_range=area_range)
            # NOTE dist_boxes with shape: [ymin, xmin, ymax, xmax] and in values in range(0, 1)
            # Employ the bounding box to distort the image.
            croped_box = [dist_boxes[0,0,1]*w, dist_boxes[0,0,0]*h, dist_boxes[0,0,3]*w, dist_boxes[0,0,2]*h]
    
            croped_xmin = tf.clip_by_value(xmin, croped_box[0], croped_box[2])-croped_box[0]
            croped_ymin = tf.clip_by_value(ymin, croped_box[1], croped_box[3])-croped_box[1]
            croped_xmax = tf.clip_by_value(xmax, croped_box[0], croped_box[2])-croped_box[0]
            croped_ymax = tf.clip_by_value(ymax, croped_box[1], croped_box[3])-croped_box[1]
    
            image = tf.slice(image, begin, size)
            gt_boxes = tf.stack([croped_xmin, croped_ymin, croped_xmax, croped_ymax, label], axis=1)
    
            return image, gt_boxes
    
        def preprocess(self, image, gt_boxes):
    
            ################################# data augmentation ##################################
            # data_aug_flag = tf.to_int32(tf.random_uniform(shape=[], minval=-5, maxval=5))
    
            # caseO = tf.equal(data_aug_flag, 1), lambda: self.flip_left_right(image, gt_boxes)
            # case1 = tf.equal(data_aug_flag, 2), lambda: self.random_distort_color(image, gt_boxes)
            # case2 = tf.equal(data_aug_flag, 3), lambda: self.random_blur(image, gt_boxes)
            # case3 = tf.equal(data_aug_flag, 4), lambda: self.random_crop(image, gt_boxes)
    
            # image, gt_boxes = tf.case([caseO, case1, case2, case3], lambda: (image, gt_boxes))
    
            image, gt_boxes = utils.resize_image_correct_bbox(image, gt_boxes, self.image_h, self.image_w)
    
            if self.debug: return image, gt_boxes
    
            y_true_13, y_true_26, y_true_52 = tf.py_func(self.preprocess_true_boxes, inp=[gt_boxes],
                                Tout = [tf.float32, tf.float32, tf.float32])
            image = image / 255.
    
            return image, y_true_13, y_true_26, y_true_52
    
        def preprocess_true_boxes(self, gt_boxes):
            """
            Preprocess true boxes to training input format
            Parameters:
            -----------
            :param true_boxes: numpy.ndarray of shape [T, 4]
                                T: the number of boxes in each image.
                                4: coordinate => x_min, y_min, x_max, y_max
            :param true_labels: class id
            :param input_shape: the shape of input image to the yolov3 network, [416, 416]
            :param anchors: array, shape=[9,2], 9: the number of anchors, 2: width, height
            :param num_classes: integer, for coco dataset, it is 80
            Returns:
            ----------
            y_true: list(3 array), shape like yolo_outputs, [13, 13, 3, 85]
                                13:cell szie, 3:number of anchors
                                85: box_centers, box_sizes, confidence, probability
            """
            num_layers = len(self.anchors) // 3
            anchor_mask = [[6,7,8], [3,4,5], [0,1,2]] if num_layers==3 else [[3,4,5], [1,2,3]]
            grid_sizes = [[self.image_h//x, self.image_w//x] for x in (32, 16, 8)]
    
            box_centers = (gt_boxes[:, 0:2] + gt_boxes[:, 2:4]) / 2 # the center of box
            box_sizes =    gt_boxes[:, 2:4] - gt_boxes[:, 0:2] # the height and width of box
    
            gt_boxes[:, 0:2] = box_centers
            gt_boxes[:, 2:4] = box_sizes
    
            y_true_13 = np.zeros(shape=[grid_sizes[0][0], grid_sizes[0][1], 3, 5+self.num_classes], dtype=np.float32)
            y_true_26 = np.zeros(shape=[grid_sizes[1][0], grid_sizes[1][1], 3, 5+self.num_classes], dtype=np.float32)
            y_true_52 = np.zeros(shape=[grid_sizes[2][0], grid_sizes[2][1], 3, 5+self.num_classes], dtype=np.float32)
    
            y_true = [y_true_13, y_true_26, y_true_52]
            anchors_max =  self.anchors / 2.
            anchors_min = -anchors_max
            valid_mask = box_sizes[:, 0] > 0
    
            # Discard zero rows.
            wh = box_sizes[valid_mask]
            # set the center of all boxes as the origin of their coordinates
            # and correct their coordinates
            wh = np.expand_dims(wh, -2)
            boxes_max = wh / 2.
            boxes_min = -boxes_max
    
            intersect_mins = np.maximum(boxes_min, anchors_min)
            intersect_maxs = np.minimum(boxes_max, anchors_max)
            intersect_wh   = np.maximum(intersect_maxs - intersect_mins, 0.)
            intersect_area = intersect_wh[..., 0] * intersect_wh[..., 1]
            box_area       = wh[..., 0] * wh[..., 1]
    
            anchor_area = self.anchors[:, 0] * self.anchors[:, 1]
            iou = intersect_area / (box_area + anchor_area - intersect_area)
            # Find best anchor for each true box
            best_anchor = np.argmax(iou, axis=-1)
    
            for t, n in enumerate(best_anchor):
                for l in range(num_layers):
                    if n not in anchor_mask[l]: continue
    
                    i = np.floor(gt_boxes[t,0]/self.image_w*grid_sizes[l][1]).astype('int32')
                    j = np.floor(gt_boxes[t,1]/self.image_h*grid_sizes[l][0]).astype('int32')
    
                    k = anchor_mask[l].index(n)
                    c = gt_boxes[t, 4].astype('int32')
    
                    y_true[l][j, i, k, 0:4] = gt_boxes[t, 0:4]
                    y_true[l][j, i, k,   4] = 1.
                    y_true[l][j, i, k, 5+c] = 1.
    
            return y_true_13, y_true_26, y_true_52
    
        def parser_example(self, serialized_example):
    
            features = tf.parse_single_example(
                serialized_example,
                features = {
                    'image' : tf.FixedLenFeature([], dtype = tf.string),
                    'boxes' : tf.FixedLenFeature([], dtype = tf.string),
                }
            )
    
            image = tf.image.decode_jpeg(features['image'], channels = 3)
            image = tf.image.convert_image_dtype(image, tf.uint8)
    
            gt_boxes = tf.decode_raw(features['boxes'], tf.float32)
            gt_boxes = tf.reshape(gt_boxes, shape=[-1,5])
    
            return self.preprocess(image, gt_boxes)
    
    class dataset(object):
        def __init__(self, parser, tfrecords_path, batch_size, shuffle=None, repeat=True):
            self.parser = parser
            self.filenames = tf.gfile.Glob(tfrecords_path)
            self.batch_size = batch_size
            self.shuffle = shuffle
            self.repeat  = repeat
            self._buildup()
    
        def _buildup(self):
            try:
                self._TFRecordDataset = tf.data.TFRecordDataset(self.filenames)
            except:
                raise NotImplementedError("No tfrecords found!")
    
            self._TFRecordDataset = self._TFRecordDataset.map(map_func = self.parser.parser_example,
                                                            num_parallel_calls = 10)
            self._TFRecordDataset = self._TFRecordDataset.repeat() if self.repeat else self._TFRecordDataset
    
            if self.shuffle is not None:
                self._TFRecordDataset = self._TFRecordDataset.shuffle(self.shuffle)
    
            self._TFRecordDataset = self._TFRecordDataset.batch(self.batch_size).prefetch(self.batch_size)
            self._iterator = self._TFRecordDataset.make_one_shot_iterator()
    
        def get_next(self):
            return self._iterator.get_next()
    View Code

      |-------utils.py # NMS,画检测框,从PB文件读取Tensors,计算MAP,FREEZE_GRAPH,加载权重文件,IOU计算

    import colorsys
    import numpy as np
    import tensorflow as tf
    from collections import Counter
    from PIL import ImageFont, ImageDraw
    
    # Discard all boxes with low scores and high IOU
    def gpu_nms(boxes, scores, num_classes, max_boxes=50, score_thresh=0.3, iou_thresh=0.5):
        """
        /*----------------------------------- NMS on gpu ---------------------------------------*/
    
        Arguments:
                boxes  -- tensor of shape [1, 10647, 4] # 10647 boxes
                scores -- tensor of shape [1, 10647, num_classes], scores of boxes
                classes -- the return value of function `read_coco_names`
        Note:Applies Non-max suppression (NMS) to set of boxes. Prunes away boxes that have high
        intersection-over-union (IOU) overlap with previously selected boxes.
    
        max_boxes -- integer, maximum number of predicted boxes you'd like, default is 20
        score_thresh -- real value, if [ highest class probability score < score_threshold]
                           then get rid of the corresponding box
        iou_thresh -- real value, "intersection over union" threshold used for NMS filtering
        """
    
        boxes_list, label_list, score_list = [], [], []
        max_boxes = tf.constant(max_boxes, dtype='int32')
    
        # since we do nms for single image, then reshape it
        boxes = tf.reshape(boxes, [-1,4]) # '-1' means we don't konw the exact number of boxes
        # confs = tf.reshape(confs, [-1,1])
        score = tf.reshape(scores, [-1,num_classes])
    
        # Step 1: Create a filtering mask based on "box_class_scores" by using "threshold".
        mask = tf.greater_equal(score, tf.constant(score_thresh))
        # Step 2: Do non_max_suppression for each class
        for i in range(num_classes):
            # Step 3: Apply the mask to scores, boxes and pick them out
            filter_boxes = tf.boolean_mask(boxes, mask[:,i])
            filter_score = tf.boolean_mask(score[:,i], mask[:,i])
            nms_indices = tf.image.non_max_suppression(boxes=filter_boxes,
                                                       scores=filter_score,
                                                       max_output_size=max_boxes,
                                                       iou_threshold=iou_thresh, name='nms_indices')
            label_list.append(tf.ones_like(tf.gather(filter_score, nms_indices), 'int32')*i)
            boxes_list.append(tf.gather(filter_boxes, nms_indices))
            score_list.append(tf.gather(filter_score, nms_indices))
    
        boxes = tf.concat(boxes_list, axis=0)
        score = tf.concat(score_list, axis=0)
        label = tf.concat(label_list, axis=0)
    
        return boxes, score, label
    
    
    def py_nms(boxes, scores, max_boxes=50, iou_thresh=0.5):
        """
        Pure Python NMS baseline.
    
        Arguments: boxes => shape of [-1, 4], the value of '-1' means that dont know the
                            exact number of boxes
                   scores => shape of [-1,]
                   max_boxes => representing the maximum of boxes to be selected by non_max_suppression
                   iou_thresh => representing iou_threshold for deciding to keep boxes
        """
        assert boxes.shape[1] == 4 and len(scores.shape) == 1
    
        x1 = boxes[:, 0]
        y1 = boxes[:, 1]
        x2 = boxes[:, 2]
        y2 = boxes[:, 3]
    
        areas = (x2 - x1 + 1) * (y2 - y1 + 1)
        order = scores.argsort()[::-1]
    
        keep = []
        while order.size > 0:
            i = order[0]
            keep.append(i)
            xx1 = np.maximum(x1[i], x1[order[1:]])
            yy1 = np.maximum(y1[i], y1[order[1:]])
            xx2 = np.minimum(x2[i], x2[order[1:]])
            yy2 = np.minimum(y2[i], y2[order[1:]])
    
            w = np.maximum(0.0, xx2 - xx1 + 1)
            h = np.maximum(0.0, yy2 - yy1 + 1)
            inter = w * h
            ovr = inter / (areas[i] + areas[order[1:]] - inter)
    
            inds = np.where(ovr <= iou_thresh)[0]
            order = order[inds + 1]
    
        return keep[:max_boxes]
    
    def cpu_nms(boxes, scores, num_classes, max_boxes=50, score_thresh=0.3, iou_thresh=0.5):
        """
        /*----------------------------------- NMS on cpu ---------------------------------------*/
        Arguments:
            boxes ==> shape [1, 10647, 4]
            scores ==> shape [1, 10647, num_classes]
        """
    
        boxes = boxes.reshape(-1, 4)
        scores = scores.reshape(-1, num_classes)
        # Picked bounding boxes
        picked_boxes, picked_score, picked_label = [], [], []
    
        for i in range(num_classes):
            indices = np.where(scores[:,i] >= score_thresh)
            filter_boxes = boxes[indices]
            filter_scores = scores[:,i][indices]
            if len(filter_boxes) == 0: continue
            # do non_max_suppression on the cpu
            indices = py_nms(filter_boxes, filter_scores,
                             max_boxes=max_boxes, iou_thresh=iou_thresh)
            picked_boxes.append(filter_boxes[indices])
            picked_score.append(filter_scores[indices])
            picked_label.append(np.ones(len(indices), dtype='int32')*i)
        if len(picked_boxes) == 0: return None, None, None
    
        boxes = np.concatenate(picked_boxes, axis=0)
        score = np.concatenate(picked_score, axis=0)
        label = np.concatenate(picked_label, axis=0)
    
        return boxes, score, label
    
    def resize_image_correct_bbox(image, boxes, image_h, image_w):
    
        origin_image_size = tf.to_float(tf.shape(image)[0:2])
        image = tf.image.resize_images(image, size=[image_h, image_w])
    
        # correct bbox
        xx1 = boxes[:, 0] * image_w / origin_image_size[1]
        yy1 = boxes[:, 1] * image_h / origin_image_size[0]
        xx2 = boxes[:, 2] * image_w / origin_image_size[1]
        yy2 = boxes[:, 3] * image_h / origin_image_size[0]
        idx = boxes[:, 4]
    
        boxes = tf.stack([xx1, yy1, xx2, yy2, idx], axis=1)
        return image, boxes
    
    
    def draw_boxes(image, boxes, scores, labels, classes, detection_size,
                   font='./data/font/FiraMono-Medium.otf', show=True):
        """
        :param boxes, shape of  [num, 4]
        :param scores, shape of [num, ]
        :param labels, shape of [num, ]
        :param image,
        :param classes, the return list from the function `read_coco_names`
        """
        if boxes is None: return image
        draw = ImageDraw.Draw(image)
        # draw settings
        font = ImageFont.truetype(font = font, size = np.floor(2e-2 * image.size[1]).astype('int32'))
        hsv_tuples = [( x / len(classes), 0.9, 1.0) for x in range(len(classes))]
        colors = list(map(lambda x: colorsys.hsv_to_rgb(*x), hsv_tuples))
        colors = list(map(lambda x: (int(x[0] * 255), int(x[1] * 255), int(x[2] * 255)), colors))
        for i in range(len(labels)): # for each bounding box, do:
            bbox, score, label = boxes[i], scores[i], classes[labels[i]]
            bbox_text = "%s %.2f" %(label, score)
            text_size = draw.textsize(bbox_text, font)
            # convert_to_original_size
            detection_size, original_size = np.array(detection_size), np.array(image.size)
            ratio = original_size / detection_size
            bbox = list((bbox.reshape(2,2) * ratio).reshape(-1))
    
            draw.rectangle(bbox, outline=colors[labels[i]], width=3)
            text_origin = bbox[:2]-np.array([0, text_size[1]])
            draw.rectangle([tuple(text_origin), tuple(text_origin+text_size)], fill=colors[labels[i]])
            # # draw bbox
            draw.text(tuple(text_origin), bbox_text, fill=(0,0,0), font=font)
    
        image.show() if show else None
        return image
    
    def read_coco_names(class_file_name):
        names = {}
        with open(class_file_name, 'r') as data:
            for ID, name in enumerate(data):
                names[ID] = name.strip('
    ')
        return names
    
    
    
    def freeze_graph(sess, output_file, output_node_names):
    
        output_graph_def = tf.graph_util.convert_variables_to_constants(
            sess,
            sess.graph.as_graph_def(),
            output_node_names,
        )
    
        with tf.gfile.GFile(output_file, "wb") as f:
            f.write(output_graph_def.SerializeToString())
    
        print("=> {} ops written to {}.".format(len(output_graph_def.node), output_file))
    
    
    def read_pb_return_tensors(graph, pb_file, return_elements):
    
        with tf.gfile.FastGFile(pb_file, 'rb') as f:
            frozen_graph_def = tf.GraphDef()
            frozen_graph_def.ParseFromString(f.read())
    
        with graph.as_default():
            return_elements = tf.import_graph_def(frozen_graph_def,
                                                  return_elements=return_elements)
            input_tensor, output_tensors = return_elements[0], return_elements[1:]
    
        return input_tensor, output_tensors
    
    
    def load_weights(var_list, weights_file):
        """
        Loads and converts pre-trained weights.
        :param var_list: list of network variables.
        :param weights_file: name of the binary file.
        :return: list of assign ops
        """
        with open(weights_file, "rb") as fp:
            np.fromfile(fp, dtype=np.int32, count=5)
            weights = np.fromfile(fp, dtype=np.float32)
    
        ptr = 0
        i = 0
        assign_ops = []
        while i < len(var_list) - 1:
            var1 = var_list[i]
            print("=> loading ", var1.name)
            var2 = var_list[i + 1]
            print("=> loading ", var2.name)
            # do something only if we process conv layer
            if 'Conv' in var1.name.split('/')[-2]:
                # check type of next layer
                if 'BatchNorm' in var2.name.split('/')[-2]:
                    # load batch norm params
                    gamma, beta, mean, var = var_list[i + 1:i + 5]
                    batch_norm_vars = [beta, gamma, mean, var]
                    for var in batch_norm_vars:
                        shape = var.shape.as_list()
                        num_params = np.prod(shape)
                        var_weights = weights[ptr:ptr + num_params].reshape(shape)
                        ptr += num_params
                        assign_ops.append(tf.assign(var, var_weights, validate_shape=True))
                    # we move the pointer by 4, because we loaded 4 variables
                    i += 4
                elif 'Conv' in var2.name.split('/')[-2]:
                    # load biases
                    bias = var2
                    bias_shape = bias.shape.as_list()
                    bias_params = np.prod(bias_shape)
                    bias_weights = weights[ptr:ptr +
                                           bias_params].reshape(bias_shape)
                    ptr += bias_params
                    assign_ops.append(tf.assign(bias, bias_weights, validate_shape=True))
                    # we loaded 1 variable
                    i += 1
                # we can load weights of conv layer
                shape = var1.shape.as_list()
                num_params = np.prod(shape)
    
                var_weights = weights[ptr:ptr + num_params].reshape(
                    (shape[3], shape[2], shape[0], shape[1]))
                # remember to transpose to column-major
                var_weights = np.transpose(var_weights, (2, 3, 1, 0))
                ptr += num_params
                assign_ops.append(
                    tf.assign(var1, var_weights, validate_shape=True))
                i += 1
    
        return assign_ops
    
    
    def get_anchors(anchors_path, image_h, image_w):
        '''loads the anchors from a file'''
        with open(anchors_path) as f:
            anchors = f.readline()
        anchors = np.array(anchors.split(), dtype=np.float32)
        anchors = anchors.reshape(-1,2)
        anchors[:, 1] = anchors[:, 1] * image_h
        anchors[:, 0] = anchors[:, 0] * image_w
        return anchors.astype(np.int32)
    
    
    def bbox_iou(A, B):
    
        intersect_mins = np.maximum(A[:, 0:2], B[:, 0:2])
        intersect_maxs = np.minimum(A[:, 2:4], B[:, 2:4])
        intersect_wh   = np.maximum(intersect_maxs - intersect_mins, 0.)
        intersect_area = intersect_wh[..., 0] * intersect_wh[..., 1]
    
        A_area = np.prod(A[:, 2:4] - A[:, 0:2], axis=1)
        B_area = np.prod(B[:, 2:4] - B[:, 0:2], axis=1)
    
        iou = intersect_area / (A_area + B_area - intersect_area)
    
        return iou
    
    def evaluate(y_pred, y_true, iou_thresh=0.5, score_thresh=0.3):
    
        num_images  = y_true[0].shape[0]
        num_classes = y_true[0][0][..., 5:].shape[-1]
        true_labels_dict   = {i:0 for i in range(num_classes)} # {class: count}
        pred_labels_dict   = {i:0 for i in range(num_classes)}
        true_positive_dict = {i:0 for i in range(num_classes)}
    
        for i in range(num_images):
            true_labels_list, true_boxes_list = [], []
            for j in range(3): # three feature maps
                true_probs_temp = y_true[j][i][...,5: ]
                true_boxes_temp = y_true[j][i][...,0:4]
    
                object_mask = true_probs_temp.sum(axis=-1) > 0
    
                true_probs_temp = true_probs_temp[object_mask]
                true_boxes_temp = true_boxes_temp[object_mask]
    
                true_labels_list += np.argmax(true_probs_temp, axis=-1).tolist()
                true_boxes_list  += true_boxes_temp.tolist()
    
            if len(true_labels_list) != 0:
                for cls, count in Counter(true_labels_list).items(): true_labels_dict[cls] += count
    
            pred_boxes = y_pred[0][i:i+1]
            pred_confs = y_pred[1][i:i+1]
            pred_probs = y_pred[2][i:i+1]
    
            pred_boxes, pred_scores, pred_labels = cpu_nms(pred_boxes, pred_confs*pred_probs, num_classes,
                                                          score_thresh=score_thresh, iou_thresh=iou_thresh)
    
            true_boxes = np.array(true_boxes_list)
            box_centers, box_sizes = true_boxes[:,0:2], true_boxes[:,2:4]
    
            true_boxes[:,0:2] = box_centers - box_sizes / 2.
            true_boxes[:,2:4] = true_boxes[:,0:2] + box_sizes
            pred_labels_list = [] if pred_labels is None else pred_labels.tolist()
    
            if len(pred_labels_list) != 0:
                for cls, count in Counter(pred_labels_list).items(): pred_labels_dict[cls] += count
            else:
                continue
    
            detected = []
            for k in range(len(pred_labels_list)):
                # compute iou between predicted box and ground_truth boxes
                iou = bbox_iou(pred_boxes[k:k+1], true_boxes)
                m = np.argmax(iou) # Extract index of largest overlap
                if iou[m] >= iou_thresh and pred_labels_list[k] == true_labels_list[m] and m not in detected:
                    true_positive_dict[true_labels_list[m]] += 1
                    detected.append(m)
    
    
        recall    = sum(true_positive_dict.values()) / (sum(true_labels_dict.values()) + 1e-6)
        precision = sum(true_positive_dict.values()) / (sum(pred_labels_dict.values()) + 1e-6)
    
        return recall, precision
    
    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(([0.0], recall, [1.0]))
        mpre = np.concatenate(([0.0], precision, [0.0]))
    
        # 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
    View Code

      |-------common.py # 卷积层Pad 使用Slim

    import tensorflow as tf
    slim = tf.contrib.slim
    
    def _conv2d_fixed_padding(inputs, filters, kernel_size, strides=1):
        if strides > 1: inputs = _fixed_padding(inputs, kernel_size)
        inputs = slim.conv2d(inputs, filters, kernel_size, stride=strides,
                             padding=('SAME' if strides == 1 else 'VALID'))
        return inputs
    
    
    @tf.contrib.framework.add_arg_scope
    def _fixed_padding(inputs, kernel_size, *args, mode='CONSTANT', **kwargs):
        """
        Pads the input along the spatial dimensions independently of input size.
    
        Args:
          inputs: A tensor of size [batch, channels, height_in, width_in] or
            [batch, height_in, width_in, channels] depending on data_format.
          kernel_size: The kernel to be used in the conv2d or max_pool2d operation.
                       Should be a positive integer.
          mode: The mode for tf.pad.
    
        Returns:
          A tensor with the same format as the input with the data either intact
          (if kernel_size == 1) or padded (if kernel_size > 1).
        """
        pad_total = kernel_size - 1
        pad_beg = pad_total // 2
        pad_end = pad_total - pad_beg
    
        padded_inputs = tf.pad(inputs, [[0, 0], [pad_beg, pad_end],
                                        [pad_beg, pad_end], [0, 0]], mode=mode)
        return padded_inputs
    View Code

      |-------yolov3.py #定义Darknet53,yolov3

    import tensorflow as tf
    from core import common
    slim = tf.contrib.slim
    
    class darknet53(object):
        """network for performing feature extraction"""
    
        def __init__(self, inputs):
            self.outputs = self.forward(inputs)
    
        def _darknet53_block(self, inputs, filters):
            """
            implement residuals block in darknet53
            """
            shortcut = inputs
            inputs = common._conv2d_fixed_padding(inputs, filters * 1, 1)
            inputs = common._conv2d_fixed_padding(inputs, filters * 2, 3)
    
            inputs = inputs + shortcut
            return inputs
    
        def forward(self, inputs):
    
            inputs = common._conv2d_fixed_padding(inputs, 32,  3, strides=1)
            inputs = common._conv2d_fixed_padding(inputs, 64,  3, strides=2)
            inputs = self._darknet53_block(inputs, 32)
            inputs = common._conv2d_fixed_padding(inputs, 128, 3, strides=2)
    
            for i in range(2):
                inputs = self._darknet53_block(inputs, 64)
    
            inputs = common._conv2d_fixed_padding(inputs, 256, 3, strides=2)
    
            for i in range(8):
                inputs = self._darknet53_block(inputs, 128)
    
            route_1 = inputs
            inputs = common._conv2d_fixed_padding(inputs, 512, 3, strides=2)
    
            for i in range(8):
                inputs = self._darknet53_block(inputs, 256)
    
            route_2 = inputs
            inputs = common._conv2d_fixed_padding(inputs, 1024, 3, strides=2)
    
            for i in range(4):
                inputs = self._darknet53_block(inputs, 512)
    
            return route_1, route_2, inputs
    
    
    
    class yolov3(object):
    
        def __init__(self, num_classes, anchors,
                     batch_norm_decay=0.9, leaky_relu=0.1):
    
            # self._ANCHORS = [[10 ,13], [16 , 30], [33 , 23],
                             # [30 ,61], [62 , 45], [59 ,119],
                             # [116,90], [156,198], [373,326]]
            self._ANCHORS = anchors
            self._BATCH_NORM_DECAY = batch_norm_decay
            self._LEAKY_RELU = leaky_relu
            self._NUM_CLASSES = num_classes
            self.feature_maps = [] # [[None, 13, 13, 255], [None, 26, 26, 255], [None, 52, 52, 255]]
    
        def _yolo_block(self, inputs, filters):
            inputs = common._conv2d_fixed_padding(inputs, filters * 1, 1)
            inputs = common._conv2d_fixed_padding(inputs, filters * 2, 3)
            inputs = common._conv2d_fixed_padding(inputs, filters * 1, 1)
            inputs = common._conv2d_fixed_padding(inputs, filters * 2, 3)
            inputs = common._conv2d_fixed_padding(inputs, filters * 1, 1)
            route = inputs
            inputs = common._conv2d_fixed_padding(inputs, filters * 2, 3)
            return route, inputs
    
        def _detection_layer(self, inputs, anchors):
            num_anchors = len(anchors)
            feature_map = slim.conv2d(inputs, num_anchors * (5 + self._NUM_CLASSES), 1,
                                    stride=1, normalizer_fn=None,
                                    activation_fn=None,
                                    biases_initializer=tf.zeros_initializer())
            return feature_map
    
        def _reorg_layer(self, feature_map, anchors):
    
            num_anchors = len(anchors) # num_anchors=3
            grid_size = feature_map.shape.as_list()[1:3]
            # the downscale image in height and weight
            stride = tf.cast(self.img_size // grid_size, tf.float32) # [h,w] -> [y,x]
            feature_map = tf.reshape(feature_map, [-1, grid_size[0], grid_size[1], num_anchors, 5 + self._NUM_CLASSES])
    
            box_centers, box_sizes, conf_logits, prob_logits = tf.split(
                feature_map, [2, 2, 1, self._NUM_CLASSES], axis=-1)
    
            box_centers = tf.nn.sigmoid(box_centers)
    
            grid_x = tf.range(grid_size[1], dtype=tf.int32)
            grid_y = tf.range(grid_size[0], dtype=tf.int32)
    
            a, b = tf.meshgrid(grid_x, grid_y)
            x_offset   = tf.reshape(a, (-1, 1))
            y_offset   = tf.reshape(b, (-1, 1))
            x_y_offset = tf.concat([x_offset, y_offset], axis=-1)
            x_y_offset = tf.reshape(x_y_offset, [grid_size[0], grid_size[1], 1, 2])
            x_y_offset = tf.cast(x_y_offset, tf.float32)
    
            box_centers = box_centers + x_y_offset
            box_centers = box_centers * stride[::-1]
    
            box_sizes = tf.exp(box_sizes) * anchors # anchors -> [w, h]
            boxes = tf.concat([box_centers, box_sizes], axis=-1)
            return x_y_offset, boxes, conf_logits, prob_logits
    
        @staticmethod
        def _upsample(inputs, out_shape):
    
            new_height, new_width = out_shape[1], out_shape[2]
            inputs = tf.image.resize_nearest_neighbor(inputs, (new_height, new_width))
            inputs = tf.identity(inputs, name='upsampled')
    
            return inputs
    
        # @staticmethod
        # def _upsample(inputs, out_shape):
            # """
            # replace resize_nearest_neighbor with conv2d_transpose To support TensorRT 5 optimization
            # """
            # new_height, new_width = out_shape[1], out_shape[2]
            # filters = 256 if (new_height == 26 and new_width==26) else 128
            # inputs = tf.layers.conv2d_transpose(inputs, filters, kernel_size=3, padding='same',
                                                # strides=(2,2), kernel_initializer=tf.ones_initializer())
            # return inputs
    
        def forward(self, inputs, is_training=False, reuse=False):
            """
            Creates YOLO v3 model.
    
            :param inputs: a 4-D tensor of size [batch_size, height, width, channels].
                   Dimension batch_size may be undefined. The channel order is RGB.
            :param is_training: whether is training or not.
            :param reuse: whether or not the network and its variables should be reused.
            :return:
            """
            # it will be needed later on
            self.img_size = tf.shape(inputs)[1:3]
            # set batch norm params
            batch_norm_params = {
                'decay': self._BATCH_NORM_DECAY,
                'epsilon': 1e-05,
                'scale': True,
                'is_training': is_training,
                'fused': None,  # Use fused batch norm if possible.
            }
    
            # Set activation_fn and parameters for conv2d, batch_norm.
            with slim.arg_scope([slim.conv2d, slim.batch_norm, common._fixed_padding],reuse=reuse):
                with slim.arg_scope([slim.conv2d], normalizer_fn=slim.batch_norm,
                                    normalizer_params=batch_norm_params,
                                    biases_initializer=None,
                                    activation_fn=lambda x: tf.nn.leaky_relu(x, alpha=self._LEAKY_RELU)):
                    with tf.variable_scope('darknet-53'):
                        route_1, route_2, inputs = darknet53(inputs).outputs
    
                    with tf.variable_scope('yolo-v3'):
                        route, inputs = self._yolo_block(inputs, 512)
                        feature_map_1 = self._detection_layer(inputs, self._ANCHORS[6:9])
                        feature_map_1 = tf.identity(feature_map_1, name='feature_map_1')
    
                        inputs = common._conv2d_fixed_padding(route, 256, 1)
                        upsample_size = route_2.get_shape().as_list()
                        inputs = self._upsample(inputs, upsample_size)
                        inputs = tf.concat([inputs, route_2], axis=3)
    
                        route, inputs = self._yolo_block(inputs, 256)
                        feature_map_2 = self._detection_layer(inputs, self._ANCHORS[3:6])
                        feature_map_2 = tf.identity(feature_map_2, name='feature_map_2')
    
                        inputs = common._conv2d_fixed_padding(route, 128, 1)
                        upsample_size = route_1.get_shape().as_list()
                        inputs = self._upsample(inputs, upsample_size)
                        inputs = tf.concat([inputs, route_1], axis=3)
    
                        route, inputs = self._yolo_block(inputs, 128)
                        feature_map_3 = self._detection_layer(inputs, self._ANCHORS[0:3])
                        feature_map_3 = tf.identity(feature_map_3, name='feature_map_3')
    
                return feature_map_1, feature_map_2, feature_map_3
    
        def _reshape(self, x_y_offset, boxes, confs, probs):
    
            grid_size = x_y_offset.shape.as_list()[:2]
            boxes = tf.reshape(boxes, [-1, grid_size[0]*grid_size[1]*3, 4])
            confs = tf.reshape(confs, [-1, grid_size[0]*grid_size[1]*3, 1])
            probs = tf.reshape(probs, [-1, grid_size[0]*grid_size[1]*3, self._NUM_CLASSES])
    
            return boxes, confs, probs
    
        def predict(self, feature_maps):
            """
            Note: given by feature_maps, compute the receptive field
                  and get boxes, confs and class_probs
            input_argument: feature_maps -> [None, 13, 13, 255],
                                            [None, 26, 26, 255],
                                            [None, 52, 52, 255],
            """
            feature_map_1, feature_map_2, feature_map_3 = feature_maps
            feature_map_anchors = [(feature_map_1, self._ANCHORS[6:9]),
                                   (feature_map_2, self._ANCHORS[3:6]),
                                   (feature_map_3, self._ANCHORS[0:3]),]
    
            results = [self._reorg_layer(feature_map, anchors) for (feature_map, anchors) in feature_map_anchors]
            boxes_list, confs_list, probs_list = [], [], []
    
            for result in results:
                boxes, conf_logits, prob_logits = self._reshape(*result)
    
                confs = tf.sigmoid(conf_logits)
                probs = tf.sigmoid(prob_logits)
    
                boxes_list.append(boxes)
                confs_list.append(confs)
                probs_list.append(probs)
    
            boxes = tf.concat(boxes_list, axis=1)
            confs = tf.concat(confs_list, axis=1)
            probs = tf.concat(probs_list, axis=1)
    
            center_x, center_y, width, height = tf.split(boxes, [1,1,1,1], axis=-1)
            x0 = center_x - width   / 2.
            y0 = center_y - height  / 2.
            x1 = center_x + width   / 2.
            y1 = center_y + height  / 2.
    
            boxes = tf.concat([x0, y0, x1, y1], axis=-1)
            return boxes, confs, probs
    
        def compute_loss(self, pred_feature_map, y_true, ignore_thresh=0.5, max_box_per_image=8):
            """
            Note: compute the loss
            Arguments: y_pred, list -> [feature_map_1, feature_map_2, feature_map_3]
                                            the shape of [None, 13, 13, 3*85]. etc
            """
            loss_xy, loss_wh, loss_conf, loss_class = 0., 0., 0., 0.
            total_loss = 0.
            # total_loss, rec_50, rec_75,  avg_iou    = 0., 0., 0., 0.
            _ANCHORS = [self._ANCHORS[6:9], self._ANCHORS[3:6], self._ANCHORS[0:3]]
    
            for i in range(len(pred_feature_map)):
                result = self.loss_layer(pred_feature_map[i], y_true[i], _ANCHORS[i])
                loss_xy    += result[0]
                loss_wh    += result[1]
                loss_conf  += result[2]
                loss_class += result[3]
    
            total_loss = loss_xy + loss_wh + loss_conf + loss_class
            return [total_loss, loss_xy, loss_wh, loss_conf, loss_class]
    
    
        def loss_layer(self, feature_map_i, y_true, anchors):
            # size in [h, w] format! don't get messed up!
            grid_size = tf.shape(feature_map_i)[1:3]
            grid_size_ = feature_map_i.shape.as_list()[1:3]
    
            y_true = tf.reshape(y_true, [-1, grid_size_[0], grid_size_[1], 3, 5+self._NUM_CLASSES])
    
            # the downscale ratio in height and weight
            ratio = tf.cast(self.img_size / grid_size, tf.float32)
            # N: batch_size
            N = tf.cast(tf.shape(feature_map_i)[0], tf.float32)
    
            x_y_offset, pred_boxes, pred_conf_logits, pred_prob_logits = self._reorg_layer(feature_map_i, anchors)
            # shape: take 416x416 input image and 13*13 feature_map for example:
            # [N, 13, 13, 3, 1]
            object_mask = y_true[..., 4:5]
            # shape: [N, 13, 13, 3, 4] & [N, 13, 13, 3] ==> [V, 4]
            # V: num of true gt box
            valid_true_boxes = tf.boolean_mask(y_true[..., 0:4], tf.cast(object_mask[..., 0], 'bool'))
    
            # shape: [V, 2]
            valid_true_box_xy = valid_true_boxes[:, 0:2]
            valid_true_box_wh = valid_true_boxes[:, 2:4]
            # shape: [N, 13, 13, 3, 2]
            pred_box_xy = pred_boxes[..., 0:2]
            pred_box_wh = pred_boxes[..., 2:4]
    
            # calc iou
            # shape: [N, 13, 13, 3, V]
            iou = self._broadcast_iou(valid_true_box_xy, valid_true_box_wh, pred_box_xy, pred_box_wh)
    
            # shape: [N, 13, 13, 3]
            best_iou = tf.reduce_max(iou, axis=-1)
            # get_ignore_mask
            ignore_mask = tf.cast(best_iou < 0.5, tf.float32)
            # shape: [N, 13, 13, 3, 1]
            ignore_mask = tf.expand_dims(ignore_mask, -1)
            # get xy coordinates in one cell from the feature_map
            # numerical range: 0 ~ 1
            # shape: [N, 13, 13, 3, 2]
            true_xy = y_true[..., 0:2] / ratio[::-1] - x_y_offset
            pred_xy = pred_box_xy      / ratio[::-1] - x_y_offset
    
            # get_tw_th, numerical range: 0 ~ 1
            # shape: [N, 13, 13, 3, 2]
            true_tw_th = y_true[..., 2:4] / anchors
            pred_tw_th = pred_box_wh      / anchors
            # for numerical stability
            true_tw_th = tf.where(condition=tf.equal(true_tw_th, 0),
                                  x=tf.ones_like(true_tw_th), y=true_tw_th)
            pred_tw_th = tf.where(condition=tf.equal(pred_tw_th, 0),
                                  x=tf.ones_like(pred_tw_th), y=pred_tw_th)
    
            true_tw_th = tf.log(tf.clip_by_value(true_tw_th, 1e-9, 1e9))
            pred_tw_th = tf.log(tf.clip_by_value(pred_tw_th, 1e-9, 1e9))
    
            # box size punishment:
            # box with smaller area has bigger weight. This is taken from the yolo darknet C source code.
            # shape: [N, 13, 13, 3, 1]
            #why use box_loss_scale?
            box_loss_scale = 2. - (y_true[..., 2:3] / tf.cast(self.img_size[1], tf.float32)) * (y_true[..., 3:4] / tf.cast(self.img_size[0], tf.float32))
    
            # shape: [N, 13, 13, 3, 1]
            xy_loss = tf.reduce_sum(tf.square(true_xy    - pred_xy) * object_mask * box_loss_scale) / N
            wh_loss = tf.reduce_sum(tf.square(true_tw_th - pred_tw_th) * object_mask * box_loss_scale) / N
    
            # shape: [N, 13, 13, 3, 1]
            conf_pos_mask = object_mask
            conf_neg_mask = (1 - object_mask) * ignore_mask
            conf_loss_pos = conf_pos_mask * tf.nn.sigmoid_cross_entropy_with_logits(labels=object_mask, logits=pred_conf_logits)
            conf_loss_neg = conf_neg_mask * tf.nn.sigmoid_cross_entropy_with_logits(labels=object_mask, logits=pred_conf_logits)
            conf_loss = tf.reduce_sum(conf_loss_pos + conf_loss_neg) / N
    
            # shape: [N, 13, 13, 3, 1]
            class_loss = object_mask * tf.nn.sigmoid_cross_entropy_with_logits(labels=y_true[..., 5:], logits=pred_prob_logits)
            class_loss = tf.reduce_sum(class_loss) / N
    
            return xy_loss, wh_loss, conf_loss, class_loss
    
        def _broadcast_iou(self, true_box_xy, true_box_wh, pred_box_xy, pred_box_wh):
            '''
            maintain an efficient way to calculate the ios matrix between ground truth true boxes and the predicted boxes
            note: here we only care about the size match
            '''
            # shape:
            # true_box_??: [V, 2]
            # pred_box_??: [N, 13, 13, 3, 2]    
    
            # shape: [N, 13, 13, 3, 1, 2]
            pred_box_xy = tf.expand_dims(pred_box_xy, -2)
            pred_box_wh = tf.expand_dims(pred_box_wh, -2)
            
            # shape: [1, V, 2]
            true_box_xy = tf.expand_dims(true_box_xy, 0)
            true_box_wh = tf.expand_dims(true_box_wh, 0)
    
            # [N, 13, 13, 3, 1, 2] & [1, V, 2] ==> [N, 13, 13, 3, V, 2]
            intersect_mins = tf.maximum(pred_box_xy - pred_box_wh / 2.,
                                        true_box_xy - true_box_wh / 2.)
            intersect_maxs = tf.minimum(pred_box_xy + pred_box_wh / 2.,
                                        true_box_xy + true_box_wh / 2.)
            intersect_wh = tf.maximum(intersect_maxs - intersect_mins, 0.)
    
            # shape: [N, 13, 13, 3, V]
            intersect_area = intersect_wh[..., 0] * intersect_wh[..., 1]
            # shape: [N, 13, 13, 3, 1]
            pred_box_area  = pred_box_wh[..., 0]  * pred_box_wh[..., 1]
            # shape: [1, V]
            true_box_area  = true_box_wh[..., 0]  * true_box_wh[..., 1]
            # [N, 13, 13, 3, V]
            iou = intersect_area / (pred_box_area + true_box_area - intersect_area)
    
            return iou
    View Code

      |-------convert_weight.py  将darknet(c版)yolov3权重转换成tensorflow版pb

    import os
    import sys
    import wget
    import time
    import argparse
    import tensorflow as tf
    from core import yolov3, utils
    
    
    class parser(argparse.ArgumentParser):
    
        def __init__(self,description):
            super(parser, self).__init__(description)
    
            self.add_argument(
                "--ckpt_file", "-cf", default='./checkpoint/yolov3.ckpt', type=str,
                help="[default: %(default)s] The checkpoint file ...",
                metavar="<CF>",
            )
    
            self.add_argument(
                "--num_classes", "-nc", default=80, type=int,
                help="[default: %(default)s] The number of classes ...",
                metavar="<NC>",
            )
    
            self.add_argument(
                "--anchors_path", "-ap", default="./data/coco_anchors.txt", type=str,
                help="[default: %(default)s] The path of anchors ...",
                metavar="<AP>",
            )
    
            self.add_argument(
                "--weights_path", "-wp", default='./checkpoint/yolov3.weights', type=str,
                help="[default: %(default)s] Download binary file with desired weights",
                metavar="<WP>",
            )
    
            self.add_argument(
                "--convert", "-cv", action='store_true',
                help="[default: %(default)s] Downloading yolov3 weights and convert them",
            )
    
            self.add_argument(
                "--freeze", "-fz", action='store_true',
                help="[default: %(default)s] freeze the yolov3 graph to pb ...",
            )
    
            self.add_argument(
                "--image_h", "-ih", default=416, type=int,
                help="[default: %(default)s] The height of image, 416 or 608",
                metavar="<IH>",
            )
    
            self.add_argument(
                "--image_w", "-iw", default=416, type=int,
                help="[default: %(default)s] The width of image, 416 or 608",
                metavar="<IW>",
            )
    
            self.add_argument(
                "--iou_threshold", "-it", default=0.5, type=float,
                help="[default: %(default)s] The iou_threshold for gpu nms",
                metavar="<IT>",
            )
    
            self.add_argument(
                "--score_threshold", "-st", default=0.5, type=float,
                help="[default: %(default)s] The score_threshold for gpu nms",
                metavar="<ST>",
            )
    
    
    def main(argv):
    
        flags = parser(description="freeze yolov3 graph from checkpoint file").parse_args()
        print("=> the input image size is [%d, %d]" %(flags.image_h, flags.image_w))
        anchors = utils.get_anchors(flags.anchors_path, flags.image_h, flags.image_w)
        model = yolov3.yolov3(flags.num_classes, anchors)
    
        with tf.Graph().as_default() as graph:
            sess = tf.Session(graph=graph)
            inputs = tf.placeholder(tf.float32, [1, flags.image_h, flags.image_w, 3]) # placeholder for detector inputs
            print("=>", inputs)
    
            with tf.variable_scope('yolov3'):
                feature_map = model.forward(inputs, is_training=False)
    
            boxes, confs, probs = model.predict(feature_map)
            scores = confs * probs
            print("=>", boxes.name[:-2], scores.name[:-2])
            cpu_out_node_names = [boxes.name[:-2], scores.name[:-2]]
            boxes, scores, labels = utils.gpu_nms(boxes, scores, flags.num_classes,
                                                  score_thresh=flags.score_threshold,
                                                  iou_thresh=flags.iou_threshold)
            print("=>", boxes.name[:-2], scores.name[:-2], labels.name[:-2])
            gpu_out_node_names = [boxes.name[:-2], scores.name[:-2], labels.name[:-2]]
            feature_map_1, feature_map_2, feature_map_3 = feature_map
            saver = tf.train.Saver(var_list=tf.global_variables(scope='yolov3'))
    
            if flags.convert:
                if not os.path.exists(flags.weights_path):
                    url = 'https://github.com/YunYang1994/tensorflow-yolov3/releases/download/v1.0/yolov3.weights'
                    for i in range(3):
                        time.sleep(1)
                        print("=> %s does not exists ! " %flags.weights_path)
                    print("=> It will take a while to download it from %s" %url)
                    print('=> Downloading yolov3 weights ... ')
                    wget.download(url, flags.weights_path)
    
                load_ops = utils.load_weights(tf.global_variables(scope='yolov3'), flags.weights_path)
                sess.run(load_ops)
                save_path = saver.save(sess, save_path=flags.ckpt_file)
                print('=> model saved in path: {}'.format(save_path))
    
            if flags.freeze:
                saver.restore(sess, flags.ckpt_file)
                print('=> checkpoint file restored from ', flags.ckpt_file)
                utils.freeze_graph(sess, './checkpoint/yolov3_cpu_nms.pb', cpu_out_node_names)
                utils.freeze_graph(sess, './checkpoint/yolov3_gpu_nms.pb', gpu_out_node_names)
    
    
    if __name__ == "__main__": main(sys.argv)
    View Code

      |------yolov3_train.py #加载参数,数据,训练

    import tensorflow as tf
    from core import utils, yolov3
    from core.dataset import dataset, Parser
    sess = tf.Session()
    
    IMAGE_H, IMAGE_W = 416, 416
    BATCH_SIZE       = 8
    STEPS            = 2500
    LR               = 0.001 # if Nan, set 0.0005, 0.0001
    DECAY_STEPS      = 100
    DECAY_RATE       = 0.9
    SHUFFLE_SIZE     = 200
    CLASSES          = utils.read_coco_names('./data/raccoon.names')
    ANCHORS          = utils.get_anchors('./data/raccoon_anchors.txt', IMAGE_H, IMAGE_W)
    NUM_CLASSES      = len(CLASSES)
    EVAL_INTERNAL    = 100
    SAVE_INTERNAL    = 500
    
    train_tfrecord   = "./raccoon_dataset/raccoon_train.tfrecords"
    test_tfrecord    = "./raccoon_dataset/raccoon_test.tfrecords"
    
    parser   = Parser(IMAGE_H, IMAGE_W, ANCHORS, NUM_CLASSES)
    trainset = dataset(parser, train_tfrecord, BATCH_SIZE, shuffle=SHUFFLE_SIZE)
    testset  = dataset(parser, test_tfrecord , BATCH_SIZE, shuffle=None)
    
    is_training = tf.placeholder(tf.bool)
    example = tf.cond(is_training, lambda: trainset.get_next(), lambda: testset.get_next())
    
    images, *y_true = example
    model = yolov3.yolov3(NUM_CLASSES, ANCHORS)
    
    with tf.variable_scope('yolov3'):
        pred_feature_map = model.forward(images, is_training=is_training)
        loss             = model.compute_loss(pred_feature_map, y_true)
        y_pred           = model.predict(pred_feature_map)
    
    tf.summary.scalar("loss/coord_loss",   loss[1])
    tf.summary.scalar("loss/sizes_loss",   loss[2])
    
    tf.summary.scalar("loss/confs_loss",   loss[3])
    tf.summary.scalar("loss/class_loss",   loss[4])
    
    
    global_step = tf.Variable(0, trainable=False, collections=[tf.GraphKeys.LOCAL_VARIABLES])
    write_op = tf.summary.merge_all()
    writer_train = tf.summary.FileWriter("./data/train")
    writer_test  = tf.summary.FileWriter("./data/test")
    
    saver_to_restore = tf.train.Saver(var_list=tf.contrib.framework.get_variables_to_restore(include=["yolov3/darknet-53"]))
    update_vars = tf.contrib.framework.get_variables_to_restore(include=["yolov3/yolo-v3"])
    learning_rate = tf.train.exponential_decay(LR, global_step, decay_steps=DECAY_STEPS, decay_rate=DECAY_RATE, staircase=True)
    optimizer = tf.train.AdamOptimizer(learning_rate)
    
    # set dependencies for BN ops
    update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS)
    with tf.control_dependencies(update_ops):
        train_op = optimizer.minimize(loss[0], var_list=update_vars, global_step=global_step)
    
    sess.run([tf.global_variables_initializer(), tf.local_variables_initializer()])
    saver_to_restore.restore(sess, "./checkpoint/yolov3.ckpt")
    saver = tf.train.Saver(max_to_keep=2)
    
    for step in range(STEPS):
        run_items = sess.run([train_op, write_op, y_pred, y_true] + loss, feed_dict={is_training:True})
    
        if (step+1) % EVAL_INTERNAL == 0:
            train_rec_value, train_prec_value = utils.evaluate(run_items[2], run_items[3])
    
        writer_train.add_summary(run_items[1], global_step=step)
        writer_train.flush() # Flushes the event file to disk
        if (step+1) % SAVE_INTERNAL == 0: 
              saver.save(sess, save_path="./checkpoint/yolov3.ckpt", global_step=step+1)
    
        print("=> STEP %10d [TRAIN]:	loss_xy:%7.4f 	loss_wh:%7.4f 	loss_conf:%7.4f 	loss_class:%7.4f"
            %(step+1, run_items[5], run_items[6], run_items[7], run_items[8]))
    
        run_items = sess.run([write_op, y_pred, y_true] + loss, feed_dict={is_training:False})
        if (step+1) % EVAL_INTERNAL == 0:
            test_rec_value, test_prec_value = utils.evaluate(run_items[1], run_items[2])
            print("
    =======================> evaluation result <================================
    ")
            print("=> STEP %10d [TRAIN]:	recall:%7.4f 	precision:%7.4f" %(step+1, train_rec_value, train_prec_value))
            print("=> STEP %10d [VALID]:	recall:%7.4f 	precision:%7.4f" %(step+1, test_rec_value,  test_prec_value))
            print("
    =======================> evaluation result <================================
    ")
    
        writer_test.add_summary(run_items[0], global_step=step)
        writer_test.flush() # Flushes the event file to disk
    View Code

      |------evaluate.py # 评估模型效果

    import sys
    import numpy as np
    import tensorflow as tf
    from tqdm import tqdm
    from PIL import Image
    from core import utils, yolov3
    from core.dataset import dataset, Parser
    sess = tf.Session()
    
    
    IMAGE_H, IMAGE_W = 416, 416
    CLASSES          = utils.read_coco_names('./data/raccoon.names')
    NUM_CLASSES      = len(CLASSES)
    ANCHORS          = utils.get_anchors('./data/raccoon_anchors.txt', IMAGE_H, IMAGE_W)
    CKPT_FILE        = "./checkpoint/yolov3.ckpt-2500"
    IOU_THRESH       = 0.5
    SCORE_THRESH     = 0.3
    
    all_detections   = []
    all_annotations  = []
    all_aver_precs   = {CLASSES[i]:0. for i in range(NUM_CLASSES)}
    
    test_tfrecord    = "./raccoon_dataset/raccoon_*.tfrecords"
    parser           = Parser(IMAGE_H, IMAGE_W, ANCHORS, NUM_CLASSES)
    testset          = dataset(parser, test_tfrecord , batch_size=1, shuffle=None, repeat=False)
    
    
    images_tensor, *y_true_tensor  = testset.get_next()
    model = yolov3.yolov3(NUM_CLASSES, ANCHORS)
    with tf.variable_scope('yolov3'):
        pred_feature_map    = model.forward(images_tensor, is_training=False)
        y_pred_tensor       = model.predict(pred_feature_map)
    
    saver = tf.train.Saver()
    saver.restore(sess, CKPT_FILE)
    
    try:
        image_idx = 0
        while True:
            y_pred, y_true, image  = sess.run([y_pred_tensor, y_true_tensor, images_tensor])
            pred_boxes = y_pred[0][0]
            pred_confs = y_pred[1][0]
            pred_probs = y_pred[2][0]
            image      = Image.fromarray(np.uint8(image[0]*255))
    
            true_labels_list, true_boxes_list = [], []
            for i in range(3):
                true_probs_temp = y_true[i][..., 5: ]
                true_boxes_temp = y_true[i][..., 0:4]
                object_mask     = true_probs_temp.sum(axis=-1) > 0
    
                true_probs_temp = true_probs_temp[object_mask]
                true_boxes_temp = true_boxes_temp[object_mask]
    
                true_labels_list += np.argmax(true_probs_temp, axis=-1).tolist()
                true_boxes_list  += true_boxes_temp.tolist()
    
            pred_boxes, pred_scores, pred_labels = utils.cpu_nms(pred_boxes, pred_confs*pred_probs, NUM_CLASSES,
                                                          score_thresh=SCORE_THRESH, iou_thresh=IOU_THRESH)
            # image = utils.draw_boxes(image, pred_boxes, pred_scores, pred_labels, CLASSES, [IMAGE_H, IMAGE_W], show=True)
            true_boxes = np.array(true_boxes_list)
            box_centers, box_sizes = true_boxes[:,0:2], true_boxes[:,2:4]
    
            true_boxes[:,0:2] = box_centers - box_sizes / 2.
            true_boxes[:,2:4] = true_boxes[:,0:2] + box_sizes
            pred_labels_list = [] if pred_labels is None else pred_labels.tolist()
    
            all_detections.append( [pred_boxes, pred_scores, pred_labels_list])
            all_annotations.append([true_boxes, true_labels_list])
            image_idx += 1
            if image_idx % 100 == 0:
                sys.stdout.write(".")
                sys.stdout.flush()
    
    
    except tf.errors.OutOfRangeError:
        pass
    
    
    for idx in range(NUM_CLASSES):
        true_positives  = []
        scores = []
        num_annotations = 0
    
        for i in tqdm(range(len(all_annotations)), desc="Computing AP for class %12s" %(CLASSES[idx])):
            pred_boxes, pred_scores, pred_labels_list = all_detections[i]
            true_boxes, true_labels_list              = all_annotations[i]
            detected                                  = []
            num_annotations                          += true_labels_list.count(idx)
    
            for k in range(len(pred_labels_list)):
                if pred_labels_list[k] != idx: continue
    
                scores.append(pred_scores[k])
                ious = utils.bbox_iou(pred_boxes[k:k+1], true_boxes)
                m    = np.argmax(ious)
                if ious[m] > IOU_THRESH and pred_labels_list[k] == true_labels_list[m] and m not in detected:
                    detected.append(m)
                    true_positives.append(1)
                else:
                    true_positives.append(0)
    
        num_predictions = len(true_positives)
        true_positives  = np.array(true_positives)
        false_positives = np.ones_like(true_positives) - true_positives
        # sorted by score
        indices = np.argsort(-np.array(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 / np.maximum(num_annotations, np.finfo(np.float64).eps)
        precision = true_positives / np.maximum(num_predictions, np.finfo(np.float64).eps)
        # compute average precision
        average_precision = utils.compute_ap(recall, precision)
        all_aver_precs[CLASSES[idx]] = average_precision
    
    for idx in range(NUM_CLASSES):
        cls_name = CLASSES[idx]
        print("=> Class %10s - AP: %.4f" %(cls_name, all_aver_precs[cls_name]))
    
    print("=> mAP: %.4f" %(sum(all_aver_precs.values()) / NUM_CLASSES))
    View Code

      |------yolov3.py # 使用训练好的模型推理

    import numpy as np
    import tensorflow as tf
    from PIL import Image
    from core import utils
    
    
    IMAGE_H, IMAGE_W = 416, 416
    classes = utils.read_coco_names('./data/raccoon.names')
    num_classes = len(classes)
    image_path = "./raccoon_dataset/images/raccoon-182.jpg"  # 181,
    img = Image.open(image_path)
    img_resized = np.array(img.resize(size=(IMAGE_W, IMAGE_H)), dtype=np.float32)
    img_resized = img_resized / 255.
    cpu_nms_graph = tf.Graph()
    
    input_tensor, output_tensors = utils.read_pb_return_tensors(cpu_nms_graph, "./checkpoint/yolov3_cpu_nms.pb",
                                               ["Placeholder:0", "concat_9:0", "mul_6:0"])
    with tf.Session(graph=cpu_nms_graph) as sess:
        boxes, scores = sess.run(output_tensors, feed_dict={input_tensor: np.expand_dims(img_resized, axis=0)})
        boxes, scores, labels = utils.cpu_nms(boxes, scores, num_classes, score_thresh=0.3, iou_thresh=0.5)
        image = utils.draw_boxes(img, boxes, scores, labels, classes, [IMAGE_H, IMAGE_W], show=True)
    View Code

      |------show_input_image.py #显示输入图片及BBOX

    import cv2
    import numpy as np
    import tensorflow as tf
    from core import utils
    from PIL import Image
    from core.dataset import Parser, dataset
    sess = tf.Session()
    
    IMAGE_H, IMAGE_W = 416, 416
    BATCH_SIZE = 1
    SHUFFLE_SIZE = 1
    
    train_tfrecord = "./raccoon_dataset/raccoon_*.tfrecords"
    anchors        = utils.get_anchors('./data/raccoon_anchors.txt', IMAGE_H, IMAGE_W)
    classes = utils.read_coco_names('./data/raccoon.names')
    num_classes = len(classes)
    
    parser   = Parser(IMAGE_H, IMAGE_W, anchors, num_classes, debug=True)
    trainset = dataset(parser, train_tfrecord, BATCH_SIZE, shuffle=SHUFFLE_SIZE)
    
    is_training = tf.placeholder(tf.bool)
    example = trainset.get_next()
    
    for l in range(10):
        image, boxes = sess.run(example)
        image, boxes = image[0], boxes[0]
    
        n_box = len(boxes)
        for i in range(n_box):
            image = cv2.rectangle(image,(int(float(boxes[i][0])),
                                         int(float(boxes[i][1]))),
                                        (int(float(boxes[i][2])),
                                         int(float(boxes[i][3]))), (255,0,0), 1)
            label = classes[boxes[i][4]]
            image = cv2.putText(image, label, (int(float(boxes[i][0])),int(float(boxes[i][1]))),
                                cv2.FONT_HERSHEY_SIMPLEX,  .6, (0, 255, 0), 1, 2)
    
        image = Image.fromarray(np.uint8(image))
        image.show()
    View Code

      |------kmeans.py #计算输入数据中anchors的数据

    import cv2
    import argparse
    import numpy as np
    import seaborn as sns
    import matplotlib.pyplot as plt
    current_palette = list(sns.xkcd_rgb.values())
    
    def iou(box, clusters):
        """
        Calculates the Intersection over Union (IoU) between a box and k clusters.
        param:
            box: tuple or array, shifted to the origin (i. e. width and height)
            clusters: numpy array of shape (k, 2) where k is the number of clusters
        return:
            numpy array of shape (k, 0) where k is the number of clusters
        """
        x = np.minimum(clusters[:, 0], box[0])
        y = np.minimum(clusters[:, 1], box[1])
        if np.count_nonzero(x == 0) > 0 or np.count_nonzero(y == 0) > 0:
            raise ValueError("Box has no area")
    
        intersection = x * y
        box_area = box[0] * box[1]
        cluster_area = clusters[:, 0] * clusters[:, 1]
    
        iou_ = intersection / (box_area + cluster_area - intersection)
    
        return iou_
    
    
    
    def kmeans(boxes, k, dist=np.median,seed=1):
        """
        Calculates k-means clustering with the Intersection over Union (IoU) metric.
        :param boxes: numpy array of shape (r, 2), where r is the number of rows
        :param k: number of clusters
        :param dist: distance function
        :return: numpy array of shape (k, 2)
        """
        rows = boxes.shape[0]
        distances     = np.empty((rows, k)) ## N row x N cluster
        last_clusters = np.zeros((rows,))
    
        np.random.seed(seed)
    
        # initialize the cluster centers to be k items
        clusters = boxes[np.random.choice(rows, k, replace=False)]
    
        while True:
            # Step 1: allocate each item to the closest cluster centers
            for icluster in range(k): # I made change to lars76's code here to make the code faster
                distances[:,icluster] = 1 - iou(clusters[icluster], boxes)
    
            nearest_clusters = np.argmin(distances, axis=1)
    
            if (last_clusters == nearest_clusters).all():
                break
    
            # Step 2: calculate the cluster centers as mean (or median) of all the cases in the clusters.
            for cluster in range(k):
                clusters[cluster] = dist(boxes[nearest_clusters == cluster], axis=0)
            last_clusters = nearest_clusters
    
        return clusters, nearest_clusters, distances
    
    
    def parse_anno(annotation_path):
        anno = open(annotation_path, 'r')
        result = []
        for line in anno:
            s = line.strip().split(' ')
            image = cv2.imread(s[0])
            image_h, image_w = image.shape[:2]
            s = s[1:]
            box_cnt = len(s) // 5
            for i in range(box_cnt):
                x_min, y_min, x_max, y_max = float(s[i*5+0]), float(s[i*5+1]), float(s[i*5+2]), float(s[i*5+3])
                width  = (x_max - x_min) / image_w
                height = (y_max - y_min) / image_h
                result.append([width, height])
        result = np.asarray(result)
        return result
    
    
    def plot_cluster_result(clusters,nearest_clusters,WithinClusterSumDist,wh,k):
        for icluster in np.unique(nearest_clusters):
            pick = nearest_clusters==icluster
            c = current_palette[icluster]
            plt.rc('font', size=8)
            plt.plot(wh[pick,0],wh[pick,1],"p",
                     color=c,
                     alpha=0.5,label="cluster = {}, N = {:6.0f}".format(icluster,np.sum(pick)))
            plt.text(clusters[icluster,0],
                     clusters[icluster,1],
                     "c{}".format(icluster),
                     fontsize=20,color="red")
            plt.title("Clusters=%d" %k)
            plt.xlabel("width")
            plt.ylabel("height")
        plt.legend(title="Mean IoU = {:5.4f}".format(WithinClusterSumDist))
        plt.tight_layout()
        plt.savefig("./kmeans.jpg")
        plt.show()
    
    if __name__ == '__main__':
        parser = argparse.ArgumentParser()
        parser.add_argument("--dataset_txt", type=str, default="./raccoon_dataset/train.txt")
        parser.add_argument("--anchors_txt", type=str, default="./data/raccoon_anchors.txt")
        parser.add_argument("--cluster_num", type=int, default=9)
        args = parser.parse_args()
        anno_result = parse_anno(args.dataset_txt)
        clusters, nearest_clusters, distances = kmeans(anno_result, args.cluster_num)
    
        # sorted by area
        area = clusters[:, 0] * clusters[:, 1]
        indice = np.argsort(area)
        clusters = clusters[indice]
        with open(args.anchors_txt, "w") as f:
            for i in range(args.cluster_num):
                width, height = clusters[i]
                f.writelines(str(width) + " " + str(height) + " ")
    
        WithinClusterMeanDist = np.mean(distances[np.arange(distances.shape[0]),nearest_clusters])
        plot_cluster_result(clusters, nearest_clusters, 1-WithinClusterMeanDist, anno_result, args.cluster_num)
    View Code

      |------test_video.py #视频方式测试模型效果

    import cv2
    import time
    import numpy as np
    import tensorflow as tf
    from PIL import Image
    from core import utils
    
    
    IMAGE_H, IMAGE_W = 416, 416
    video_path = "./data/demo_data/road.mp4"
    video_path = 0 # use camera
    classes = utils.read_coco_names('./data/coco.names')
    num_classes = len(classes)
    input_tensor, output_tensors = utils.read_pb_return_tensors(tf.get_default_graph(),
                                                                "./checkpoint/yolov3_cpu_nms.pb",
                                                                ["Placeholder:0", "concat_9:0", "mul_6:0"])
    with tf.Session() as sess:
        vid = cv2.VideoCapture(video_path)
        while True:
            return_value, frame = vid.read()
            if return_value:
                frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
                image = Image.fromarray(frame)
            else:
                raise ValueError("No image!")
            img_resized = np.array(image.resize(size=(IMAGE_H, IMAGE_W)), dtype=np.float32)
            img_resized = img_resized / 255.
            prev_time = time.time()
    
            boxes, scores = sess.run(output_tensors, feed_dict={input_tensor: np.expand_dims(img_resized, axis=0)})
            boxes, scores, labels = utils.cpu_nms(boxes, scores, num_classes, score_thresh=0.4, iou_thresh=0.5)
            image = utils.draw_boxes(image, boxes, scores, labels, classes, (IMAGE_H, IMAGE_W), show=False)
    
            curr_time = time.time()
            exec_time = curr_time - prev_time
            result = np.asarray(image)
            info = "time: %.2f ms" %(1000*exec_time)
            cv2.putText(result, text=info, org=(50, 70), fontFace=cv2.FONT_HERSHEY_SIMPLEX,
                        fontScale=1, color=(255, 0, 0), thickness=2)
            cv2.namedWindow("result", cv2.WINDOW_AUTOSIZE)
            result = cv2.cvtColor(result, cv2.COLOR_RGB2BGR)
            cv2.imshow("result", result)
            if cv2.waitKey(1) & 0xFF == ord('q'): break
    View Code

    三、 Yolov3-tiny

    由于YOLOV3的模型过于庞大,无法用于ARM芯片。所以,这里使用了Yolov3-tiny。

     配置文件修改:

    首先,我们需要对yolov3-tiny.cfg进行编辑,
    在这个文件里,我们需要关注[yolo]和[yolo]前的一个[convolutional]
    首先将所有[yolo]里面classes修改为需要识别的类别数
    得到classes=4
    classes的含义是有多少种需要被识别的物体,这里我训练yolo识别4种物体,所以设置为4

    对所有[yolo]的前一个[convolutional]中的filters进行修改
    其取值为filters = 3 * ( classes + 5 ),由于上一步中classes=4所以这里filters取27
    到这里,yolov3-tiny.cfg就修改完毕了
    然后是修改model_data中的car_classes.txt,将待检测物体的标签填写进去,每种标签占一行。

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  • 原文地址:https://www.cnblogs.com/jimchen1218/p/11821943.html
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