第十一节，利用yolov3训练自己的数据集

1、环境配置

tensorflow1.12.0

Opencv3.4.2

keras

pycharm

2、配置yolov3

• 下载yolov3代码：https://github.com/qqwweee/keras-yolo3
• 下载权重：https://pjreddie.com/media/files/yolov3.weights，并将权重文件放在keras-yolo3-master文件下

• 执行如下命令将darknet下的yolov3配置文件转换成keras适用的h5文件。

  python convert.py yolov3.cfg yolov3.weights model_data/yolo.h5

更改了一下代码：重新编写了一个测试代码object_detection_yolo.py

# This code is written at BigVision LLC. It is based on the OpenCV project. It is subject to the license terms in the LICENSE file found in this distribution and at http://opencv.org/license.html

# Usage example:  python3 object_detection_yolo.py --video=run.mp4
#                 python3 object_detection_yolo.py --image=bird.jpg

import cv2 as cv
import argparse
import sys
import numpy as np
import os.path

# Initialize the parameters
confThreshold = 0.5  # Confidence threshold
nmsThreshold = 0.4   #Non-maximum suppression threshold
inpWidth = 416       #Width of network's input image
inpHeight = 416      #Height of network's input image

parser = argparse.ArgumentParser(description='Object Detection using YOLO in OPENCV')
parser.add_argument('--image', help='Path to image file.')
parser.add_argument('--video', help='Path to video file.')
args = parser.parse_args()

# Load names of classes
classesFile = "model_data/coco_classes.txt";
classes = None
# with open(classesFile, 'rt') as f:
#     classes = f.read().rstrip('\n').split('\n')
classes_path = os.path.expanduser(classesFile)
with open(classes_path) as f:
    class_names = f.readlines()
    classes = [c.strip() for c in class_names]

# Give the configuration and weight files for the model and load the network using them.
modelConfiguration = "yolov3.cfg";
modelWeights = "yolov3.weights";

net = cv.dnn.readNetFromDarknet(modelConfiguration, modelWeights)
net.setPreferableBackend(cv.dnn.DNN_BACKEND_OPENCV)
net.setPreferableTarget(cv.dnn.DNN_TARGET_CPU)

# Get the names of the output layers
def getOutputsNames(net):
    # Get the names of all the layers in the network
    layersNames = net.getLayerNames()
    # Get the names of the output layers, i.e. the layers with unconnected outputs
    return [layersNames[i[0] - 1] for i in net.getUnconnectedOutLayers()]

# Draw the predicted bounding box
def drawPred(classId, conf, left, top, right, bottom):
    # Draw a bounding box.
    cv.rectangle(frame, (left, top), (right, bottom), (255, 178, 50), 3)

    label = '%.2f' % conf

    # Get the label for the class name and its confidence
    if classes:
        assert(classId < len(classes))
        label = '%s:%s' % (classes[classId], label)

    #Display the label at the top of the bounding box
    labelSize, baseLine = cv.getTextSize(label, cv.FONT_HERSHEY_SIMPLEX, 0.5, 1)
    top = max(top, labelSize[1])
    cv.rectangle(frame, (left, top - round(1.5*labelSize[1])), (left + round(1.5*labelSize[0]), top + baseLine), (255, 255, 255), cv.FILLED)
    cv.putText(frame, label, (left, top), cv.FONT_HERSHEY_SIMPLEX, 0.75, (0,0,0), 1)

# Remove the bounding boxes with low confidence using non-maxima suppression
def postprocess(frame, outs):
    frameHeight = frame.shape[0]
    frameWidth = frame.shape[1]

    classIds = []
    confidences = []
    boxes = []
    # Scan through all the bounding boxes output from the network and keep only the
    # ones with high confidence scores. Assign the box's class label as the class with the highest score.
    classIds = []
    confidences = []
    boxes = []
    for out in outs:
        for detection in out:
            scores = detection[5:]
            classId = np.argmax(scores)
            confidence = scores[classId]
            if confidence > confThreshold:
                center_x = int(detection[0] * frameWidth)
                center_y = int(detection[1] * frameHeight)
                width = int(detection[2] * frameWidth)
                height = int(detection[3] * frameHeight)
                left = int(center_x - width / 2)
                top = int(center_y - height / 2)
                classIds.append(classId)
                confidences.append(float(confidence))
                boxes.append([left, top, width, height])

    # Perform non maximum suppression to eliminate redundant overlapping boxes with
    # lower confidences.
    indices = cv.dnn.NMSBoxes(boxes, confidences, confThreshold, nmsThreshold)
    for i in indices:
        i = i[0]
        box = boxes[i]
        left = box[0]
        top = box[1]
        width = box[2]
        height = box[3]
        drawPred(classIds[i], confidences[i], left, top, left + width, top + height)

# Process inputs
winName = 'Deep learning object detection in OpenCV'
#cv.namedWindow(winName, cv.WINDOW_NORMAL)

outputFile = "yolo_out_py.avi"
if (args.image):
    # Open the image file
    if not os.path.isfile(args.image):
        print("Input image file ", args.image, " doesn't exist")
        sys.exit(1)
    cap = cv.VideoCapture(args.image)
    outputFile = args.image[:-4]+'_yolo_out_py.jpg'
elif (args.video):
    # Open the video file
    if not os.path.isfile(args.video):
        print("Input video file ", args.video, " doesn't exist")
        sys.exit(1)
    cap = cv.VideoCapture(args.video)
    outputFile = args.video[:-4]+'_yolo_out_py.avi'
else:
    # Webcam input
    cap = cv.VideoCapture(0)

# Get the video writer initialized to save the output video
if (not args.image):
    vid_writer = cv.VideoWriter(outputFile, cv.VideoWriter_fourcc('M','J','P','G'), 30, (round(cap.get(cv.CAP_PROP_FRAME_WIDTH)),round(cap.get(cv.CAP_PROP_FRAME_HEIGHT))))

while cv.waitKey(1) < 0:

    # get frame from the video
    hasFrame, frame = cap.read()

    # Stop the program if reached end of video
    if not hasFrame:
        print("Done processing !!!")
        print("Output file is stored as ", outputFile)
        cv.waitKey(3000)
        break

    # Create a 4D blob from a frame.
    blob = cv.dnn.blobFromImage(frame, 1/255, (inpWidth, inpHeight), [0,0,0], 1, crop=False)

    # Sets the input to the network
    net.setInput(blob)

    # Runs the forward pass to get output of the output layers
    outs = net.forward(getOutputsNames(net))

    # Remove the bounding boxes with low confidence
    postprocess(frame, outs)

    # Put efficiency information. The function getPerfProfile returns the overall time for inference(t) and the timings for each of the layers(in layersTimes)
    t, _ = net.getPerfProfile()
    label = 'Inference time: %.2f ms' % (t * 1000.0 / cv.getTickFrequency())
    cv.putText(frame, label, (0, 15), cv.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255))

    # Write the frame with the detection boxes
    if (args.image):
        cv.imwrite(outputFile, frame.astype(np.uint8));
    else:
        vid_writer.write(frame.astype(np.uint8))

    #cv.imshow(winName, frame)

3、用自己的数据集训练

• 在工程下新建一个文件夹VOCdevkit，结构与VOC数据集格式保持一致，目录结构如下所示：

将自己的数据图片放入JPEFImages文件中，

• 生成Annotation下的文件，安装工具labelImg。安装过程可参照：

  https://blog.csdn.net/u012746060/article/details/81016993，结果如下图：

• 生成ImageSet/Main/4个文件，在VOC2007下新建一个test.py文件：

import os

import random

trainval_percent = 0.2

train_percent = 0.8

xmlfilepath = 'Annotations'

txtsavepath = 'ImageSets\Main'

total_xml = os.listdir(xmlfilepath)

num = len(total_xml)

list = range(num)

tv = int(num * trainval_percent)

tr = int(tv * train_percent)

trainval = random.sample(list, tv)

train = random.sample(trainval, tr)

ftrainval = open('ImageSets/Main/trainval.txt', 'w')

ftest = open('ImageSets/Main/test.txt', 'w')

ftrain = open('ImageSets/Main/train.txt', 'w')

fval = open('ImageSets/Main/val.txt', 'w')

for i in list:

    name = total_xml[i][:-4] + '\n'

    if i in trainval:

        ftrainval.write(name)

        if i in train:

            ftest.write(name)

        else:

            fval.write(name)

    else:

        ftrain.write(name)

ftrainval.close()

ftrain.close()

fval.close()

ftest.close()

运行代码之后，生成如下文件，VOC2007数据集制作完成。

• 生成yolo3所需的train.txt,val.txt,test.txt

  生成的数据集不能供yolov3直接使用。需要运行voc_annotation.py(迁移项目时必须重新运行，涉及路径问题） ，classes以检测两个类为例（redlight和greenlight），在voc_annotation.py需改你的数据集为：
  

  运行之后，生成如下三个文件：

文件内容如图所示：

• 修改参数文件yolo3.cfg

  打开yolo3.cfg文件。搜索yolo(共出现三次)，每次按下图都要修改：

filter：3*（5+len（classes））

classes:你要训练的类别数（我这里是训练两类）

random：原来是1，显存小改为0

• 修改model_data下的voc_classes.txt为自己训练的类别

• 修改train.py代码（用下面代码直接替换原来的代码）

"""

Retrain the YOLO model for your own dataset.

"""

import numpy as np

import keras.backend as K

from keras.layers import Input, Lambda

from keras.models import Model

from keras.callbacks import TensorBoard, ModelCheckpoint, EarlyStopping

from yolo3.model import preprocess_true_boxes, yolo_body, tiny_yolo_body, yolo_loss

from yolo3.utils import get_random_data

def _main():

    annotation_path = '2007_train.txt'

    log_dir = 'logs/000/'

    classes_path = 'model_data/voc_classes.txt'

    anchors_path = 'model_data/yolo_anchors.txt'

    class_names = get_classes(classes_path)

    anchors = get_anchors(anchors_path)

    input_shape = (416,416) # multiple of 32, hw

    model = create_model(input_shape, anchors, len(class_names) )

    train(model, annotation_path, input_shape, anchors, len(class_names), log_dir=log_dir)

def train(model, annotation_path, input_shape, anchors, num_classes, log_dir='logs/'):

    model.compile(optimizer='adam', loss={

        'yolo_loss': lambda y_true, y_pred: y_pred})

    logging = TensorBoard(log_dir=log_dir)

    checkpoint = ModelCheckpoint(log_dir + "ep{epoch:03d}-loss{loss:.3f}-val_loss{val_loss:.3f}.h5",

        monitor='val_loss', save_weights_only=True, save_best_only=True, period=1)

    batch_size = 10

    val_split = 0.1

    with open(annotation_path) as f:

        lines = f.readlines()

    np.random.shuffle(lines)

    num_val = int(len(lines)*val_split)

    num_train = len(lines) - num_val

    print('Train on {} samples, val on {} samples, with batch size {}.'.format(num_train, num_val, batch_size))

    model.fit_generator(data_generator_wrap(lines[:num_train], batch_size, input_shape, anchors, num_classes),

            steps_per_epoch=max(1, num_train//batch_size),

            validation_data=data_generator_wrap(lines[num_train:], batch_size, input_shape, anchors, num_classes),

            validation_steps=max(1, num_val//batch_size),

            epochs=500,

            initial_epoch=0)

    model.save_weights(log_dir + 'trained_weights.h5')

def get_classes(classes_path):

    with open(classes_path) as f:

        class_names = f.readlines()

    class_names = [c.strip() for c in class_names]

    return class_names

def get_anchors(anchors_path):

    with open(anchors_path) as f:

        anchors = f.readline()

    anchors = [float(x) for x in anchors.split(',')]

    return np.array(anchors).reshape(-1, 2)

def create_model(input_shape, anchors, num_classes, load_pretrained=False, freeze_body=False,

            weights_path='model_data/yolo_weights.h5'):

    K.clear_session() # get a new session

    image_input = Input(shape=(None, None, 3))

    h, w = input_shape

    num_anchors = len(anchors)

    y_true = [Input(shape=(h//{0:32, 1:16, 2:8}[l], w//{0:32, 1:16, 2:8}[l], \

        num_anchors//3, num_classes+5)) for l in range(3)]

    model_body = yolo_body(image_input, num_anchors//3, num_classes)

    print('Create YOLOv3 model with {} anchors and {} classes.'.format(num_anchors, num_classes))

    if load_pretrained:

        model_body.load_weights(weights_path, by_name=True, skip_mismatch=True)

        print('Load weights {}.'.format(weights_path))

        if freeze_body:

            # Do not freeze 3 output layers.

            num = len(model_body.layers)-7

            for i in range(num): model_body.layers[i].trainable = False

            print('Freeze the first {} layers of total {} layers.'.format(num, len(model_body.layers)))

    model_loss = Lambda(yolo_loss, output_shape=(1,), name='yolo_loss',

        arguments={'anchors': anchors, 'num_classes': num_classes, 'ignore_thresh': 0.5})(

        [*model_body.output, *y_true])

    model = Model([model_body.input, *y_true], model_loss)

    return model

def data_generator(annotation_lines, batch_size, input_shape, anchors, num_classes):

    n = len(annotation_lines)

    np.random.shuffle(annotation_lines)

    i = 0

    while True:

        image_data = []

        box_data = []

        for b in range(batch_size):

            i %= n

            image, box = get_random_data(annotation_lines[i], input_shape, random=True)

            image_data.append(image)

            box_data.append(box)

            i += 1

        image_data = np.array(image_data)

        box_data = np.array(box_data)

        y_true = preprocess_true_boxes(box_data, input_shape, anchors, num_classes)

        yield [image_data, *y_true], np.zeros(batch_size)

def data_generator_wrap(annotation_lines, batch_size, input_shape, anchors, num_classes):

    n = len(annotation_lines)

    if n==0 or batch_size<=0: return None

    return data_generator(annotation_lines, batch_size, input_shape, anchors, num_classes)

if __name__ == '__main__':

    _main()

替换完成后，千万千万值得注意的是，因为程序中有logs/000/目录，你需要创建这样一个目录，这个目录的作用就是存放自己的数据集训练得到的模型。不然程序运行到最后会因为找不到该路径而发生错误。