ComputerVision · 2020年6月27日 0

利用dlib实现人脸识别

最近也是临危受命,要把3月做的人脸识别嵌入到项目的总体系统中,为了满足“客户要求”,我对当时的代码结构进行了一些改动和增删,用时两天…我太菜了

一、人脸识别的原理

dlib是python的一个库,其配合已训练好的dat模型(检测器)可以简单地实现人脸录入与检测识别

表层原理很简单,调用检测器检测人脸并将人脸的图像特征转化成128D的特征向量并保存在csv文件中

给几个图:

漂亮姐姐i了i了

另外关于人脸框的定位:如图

主体采用Resnet生成一个128D的特征向量,resnet是采用34层的(resnet34)。

但由于resnet34最后一层神经网络里实际上有1000个神经元,所以dlib在后面加了Dense(128),所以生成的是128维度的向量

二、python实现

人脸录入源码如下:

这里我们采用opencv调用电脑摄像头进行人脸录入

支持功能:范围提醒、保存图像、命名人名(到文件夹)等等吧(健忘)

# 进行人脸录入 / face register
# 录入多张人脸 / support multi-faces
# EotStxTaB

#!/usr/bin/python3

import dlib         # 人脸处理的库 Dlib
import numpy as np  # 数据处理的库 Numpy
import cv2          # 图像处理的库 OpenCv
import os           # 读写文件
import shutil       # 读写文件

# Dlib 正向人脸检测器 / frontal face detector
detector = dlib.get_frontal_face_detector()

# OpenCv 调用摄像头 / Use camera
cap = cv2.VideoCapture(0)

# 人脸截图的计数器 / The counter for screen shoot
cnt_ss = 0

# 存储人脸的文件夹 / The folder to save face images
current_face_dir = ""

# 保存 faces images 的路径 / The directory to save images of faces
path_photos_from_camera = "C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera/"


# 1. 新建保存人脸图像文件和数据CSV文件夹
# 1. Mkdir for saving photos and csv
def pre_work_mkdir():

    # 新建文件夹  make folders to save faces images and csv
    if os.path.isdir(path_photos_from_camera):
        pass
    else:
        os.mkdir(path_photos_from_camera)


pre_work_mkdir()

'''
##### optional/可选, 默认关闭 #####
# 2. 删除之前存的人脸数据文件夹
# 2. Delete the old data of faces
def pre_work_del_old_face_folders():
    # 删除之前存的人脸数据文件夹
    # 删除 "/data_faces_from_camera/person_x/"...
    folders_rd = os.listdir(path_photos_from_camera)
    for i in range(len(folders_rd)):
        shutil.rmtree(path_photos_from_camera+folders_rd[i])

    if os.path.isfile("C:/Users/EotStxTaB/Documents/face/data/features_all.csv"):
        os.remove("C:/Users/EotStxTaB/Documents/face/data/features_all.csv")

# 这里在每次程序录入之前, 删掉之前存的人脸数据
# 如果这里打开,每次进行人脸录入的时候都会删掉之前的人脸图像文件夹 person_1/,person_2/,person_3/...
# If enable this function, it will delete all the old data in dir person_1/,person_2/,/person_3/...
# pre_work_del_old_face_folders()
##################################
'''
'''
# 3. Check people order: person_cnt
# 如果有之前录入的人脸 / If the old folders existsq
# 在之前 person_x 的序号按照 person_x+1 开始录入 / Start from person_x+1
if os.listdir("C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera/"):
    # 获取已录入的最后一个人脸序号 / Get the num of latest person
    person_list = os.listdir("C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera/")
    person_num_list = []
    for person in person_list:
        person_num_list.append(int(person.split('_')[-1]))
    person_cnt = max(person_num_list)

# 如果第一次存储或者没有之前录入的人脸, 按照 person_1 开始录入
# Start from person_1
else:
    '''
person_cnt = 0

# 之后用来控制是否保存图像的 flag / The flag to control if save
save_flag = 1

# 之后用来检查是否先按 'n' 再按 's' / The flag to check if press 'n' before 's'
press_n_flag = 0

#name = []
k = 0

while cap.isOpened():
    flag, img_rd = cap.read()
    # print(img_rd.shape)
    # It should be 480 height * 640 width in Windows and Ubuntu by default
    # Maybe 1280x720 in macOS

    kk = cv2.waitKey(1)

    img_gray = cv2.cvtColor(img_rd, cv2.COLOR_RGB2GRAY)
    
    # 人脸 / Faces
    faces = detector(img_gray, 0)

    # 待会要写的字体 / Font to write
    font = cv2.FONT_ITALIC

    # 4. 按下 'n' 新建存储人脸的文件夹 / press 'n' to create the folders for saving faces
    if kk == ord('n'):
        #person_cnt += 1
        name = input("请输入:")
        current_face_dir = path_photos_from_camera + name
        os.makedirs(current_face_dir)
        print('\n')
        print("新建的人脸文件夹 / Create folders: ", current_face_dir)

        cnt_ss = 0              # 将人脸计数器清零 / clear the cnt of faces
        press_n_flag = 1        # 已经按下 'n' / have pressed 'n'

    # 检测到人脸 / Face detected
    if len(faces) != 0:
        # 矩形框 / Show the rectangle box of face
        for k, d in enumerate(faces):
            # 计算矩形大小
            # Compute the width and height of the box
            # (x,y), (宽度width, 高度height)
            pos_start = tuple([d.left(), d.top()])
            pos_end = tuple([d.right(), d.bottom()])

            # 计算矩形框大小 / compute the size of rectangle box
            height = (d.bottom() - d.top())
            width = (d.right() - d.left())

            hh = int(height/2)
            ww = int(width/2)

            # 设置颜色 / the color of rectangle of faces detected
            color_rectangle = (255, 255, 255)

            # 判断人脸矩形框是否超出 480x640
            if (d.right()+ww) > 640 or (d.bottom()+hh > 480) or (d.left()-ww < 0) or (d.top()-hh < 0):
                cv2.putText(img_rd, "OUT OF RANGE", (20, 300), font, 0.8, (0, 0, 255), 1, cv2.LINE_AA)
                color_rectangle = (0, 0, 255)
                save_flag = 0
                if kk == ord('s'):
                    print("请调整位置 / Please adjust your position")
            else:
                color_rectangle = (255, 255, 255)
                save_flag = 1

            cv2.rectangle(img_rd,
                          tuple([d.left() - ww, d.top() - hh]),
                          tuple([d.right() + ww, d.bottom() + hh]),
                          color_rectangle, 2)

            # 根据人脸大小生成空的图像 / Create blank image according to the shape of face detected
            im_blank = np.zeros((int(height*2), width*2, 3), np.uint8)

            if save_flag:
                # 5. 按下 's' 保存摄像头中的人脸到本地 / Press 's' to save faces into local images
                if kk == ord('s'):
                    # 检查有没有先按'n'新建文件夹 / check if you have pressed 'n'
                    if press_n_flag:
                        cnt_ss += 1
                        for ii in range(height*2):
                            for jj in range(width*2):
                                im_blank[ii][jj] = img_rd[d.top()-hh + ii][d.left()-ww + jj]
                        cv2.imwrite(current_face_dir + "/img_face_" + str(cnt_ss) + ".jpg", im_blank)
                        print("写入本地 / Save into:", str(current_face_dir) + "/img_face_" + str(cnt_ss) + ".jpg")
                    else:
                        print("请在按 'S' 之前先按 'N' 来建文件夹 / Please press 'N' before 'S'")

    # 显示人脸数 / Show the numbers of faces detected
    cv2.putText(img_rd, "Faces: " + str(len(faces)), (20, 100), font, 0.8, (0, 255, 0), 1, cv2.LINE_AA)

    # 添加说明 / Add some statements
    cv2.putText(img_rd, "Face Register", (20, 40), font, 1, (0, 0, 0), 1, cv2.LINE_AA)
    cv2.putText(img_rd, "N: Create face folder", (20, 350), font, 0.8, (0, 0, 0), 1, cv2.LINE_AA)
    cv2.putText(img_rd, "S: Save current face", (20, 400), font, 0.8, (0, 0, 0), 1, cv2.LINE_AA)
    cv2.putText(img_rd, "Q: Quit", (20, 450), font, 0.8, (0, 0, 0), 1, cv2.LINE_AA)

    # 6. 按下 'q' 键退出 / Press 'q' to exit
    if kk == ord('q'):
        break

    # 如果需要摄像头窗口大小可调 / Uncomment this line if you want the camera window is resizeable
    # cv2.namedWindow("camera", 0)

    cv2.imshow("camera", img_rd)

# 释放摄像头 / Release camera and destroy all windows
cap.release()
cv2.destroyAllWindows()

接下来是转化图像为128向量

根据要求,我把csv每个都拆分开来存在各自文件夹

# 从人脸图像文件中提取人脸特征存入 CSV
# Features extraction from images and save into features_all.csv
# EotStxTaB

import cv2
import os
import dlib
from skimage import io
import csv
import numpy as np

# 要读取人脸图像文件的路径
path_images_from_camera = "C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera/"

# Dlib 正向人脸检测器
detector = dlib.get_frontal_face_detector()

# Dlib 人脸预测器
predictor = dlib.shape_predictor("C:/Users/EotStxTaB/Documents/face/data/data_dlib/shape_predictor_68_face_landmarks.dat")

# Dlib 人脸识别模型
# Face recognition model, the object maps human faces into 128D vectors
face_rec = dlib.face_recognition_model_v1("C:/Users/EotStxTaB/Documents/face/data/data_dlib/dlib_face_recognition_resnet_model_v1.dat")


# 返回单张图像的 128D 特征
def return_128d_features(path_img):
    img_rd = io.imread(path_img)
    img_gray = cv2.cvtColor(img_rd, cv2.COLOR_BGR2RGB)
    faces = detector(img_gray, 1)

    print("%-40s %-20s" % ("检测到人脸的图像 / image with faces detected:", path_img), '\n')

    # 因为有可能截下来的人脸再去检测,检测不出来人脸了
    # 所以要确保是 检测到人脸的人脸图像 拿去算特征
    if len(faces) != 0:
        shape = predictor(img_gray, faces[0])
        face_descriptor = face_rec.compute_face_descriptor(img_gray, shape)
    else:
        face_descriptor = 0
        print("no face")

    return face_descriptor


# 将文件夹中照片特征提取出来, 写入 CSV
def return_features_mean_personX(path_faces_personX):
    features_list_personX = []
    photos_list = os.listdir(path_faces_personX)
    if photos_list:
        #for i in range(len(photos_list)):
            # 调用return_128d_features()得到128d特征
            print("%-40s %-20s" % ("正在读的人脸图像 / image to read:",path_faces_personX + "/img_face_1.jpg"))
            features_128d = return_128d_features(path_faces_personX + "/img_face_1.jpg")  
            #  print(features_128d)
            # 遇到没有检测出人脸的图片跳过
            if features_128d == 0:
                i += 1
            else:
                features_list_personX.append(features_128d)
    else:
        print("文件夹内图像文件为空 / Warning: No images in " + path_faces_personX + '/', '\n')

    # 计算 128D 特征的均值
    # personX 的 N 张图像 x 128D -> 1 x 128D
    if features_list_personX:
        features_mean_personX = np.array(features_list_personX).mean(axis=0)
    else:
        features_mean_personX = '0'

    return features_mean_personX


dirct = 'C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera'
dirList=[]
n = 0
files=os.listdir(dirct)  #文件夹下所有目录的列表
#print('files:',files)
for f in files:
    if os.path.isdir(dirct + '/'+f):   #这里是绝对路径,该句判断目录是否是文件夹
        dirList.append(f)
        n=n+1
    elif os.path.isfile(dirct + '/'+f):#这里是绝对路径,该句判断目录是否是文件
        continue


for i in range(0,n):
    with open ("C:/Users/EotStxTaB/Documents/face/data/data_faces_from_camera/"+dirList[i]+"/features.csv", "w", newline='') as csvfile:
        writer = csv.writer(csvfile)
        features_mean_personX = return_features_mean_personX(path_images_from_camera + dirList[i])
        writer.writerow(features_mean_personX)

接下来是大改的地方,由于莫名的计算延时很高,我把识别多脸改成了图像里最大的脸(hhhh)

同时改成了输出输入是单张图片,为了兼容项目系统中的另外一个摄像头

# EotStxTaB

import dlib          # 人脸处理的库 Dlib
from dlib import dlib  #vscode的专属错误解决方式,cv2与此相同
import numpy as np   # 数据处理的库 numpy
import cv2           # 图像处理的库 OpenCv
from cv2 import cv2
import pandas as pd  # 数据处理的库 Pandas
import matplotlib.pyplot as plt
import os
import csv

# 人脸识别模型,提取128D的特征矢量
facerec = dlib.face_recognition_model_v1("./data/data_dlib/dlib_face_recognition_resnet_model_v1.dat")


# 计算两个128D向量间的欧式距离
def return_euclidean_distance(feature_1, feature_2):
    feature_1 = np.array(feature_1)
    feature_2 = np.array(feature_2)
    dist = np.sqrt(np.sum(np.square(feature_1 - feature_2)))
    return dist

detector = dlib.get_frontal_face_detector()
predictor = dlib.shape_predictor('./data/data_dlib/shape_predictor_68_face_landmarks.dat')

img_rd = cv2.imread('./data/input.jpg',cv2.IMREAD_UNCHANGED)
img_gray = cv2.cvtColor(img_rd,cv2.COLOR_RGB2GRAY)
faces = detector(img_gray, 0)

face=max(faces, key=lambda rect: rect.width() * rect.height())
#[x1,x2,y1,y2]=[face.left(),face.right(),face.top(),face.bottom()]

n=0
dirct = './data/data_faces_from_camera'
dirList=[]
files=os.listdir(dirct)  #文件夹下所有目录的列表
for f in files:
    if os.path.isdir(dirct + '/'+f):   #这里是绝对路径,该句判断目录是否是文件夹
        dirList.append(f)
        n=n+1
    elif os.path.isfile(dirct + '/'+f): #这里是绝对路径,该句判断目录是否是文件
        continue

# 待会要写的字体 font to write later
font = cv2.FONT_ITALIC
#font = cv2.FONT_HERSHEY_SCRIPT_SIMPLEX#手写花体

shape = predictor(img_rd, face)
features_cap_arr=(facerec.compute_face_descriptor(img_rd, shape))
#print(features_cap_arr)
    
for m in range(0,n):
    cs_rd = []
    path_features_known_csv = "./data/data_faces_from_camera/"+dirList[m]+"/features.csv"
    df = pd.read_csv(path_features_known_csv,engine='python')#据说也是vscode专属错误
    file=open(path_features_known_csv,'r')  #打开文件
    df=csv.reader(file)         #读取文件内容
    for stu in df:             #一行是一个数组
        for i in range (0,128):
            cs_rd.append(float(stu[i]))            #取每个数组的第一个元素
    #print(cs_rd)

    # 让人名跟随在矩形框的下方
    # 确定人名的位置坐标
    # 先默认所有人不认识,是 unknown
    name = "unknown"

    # 每个捕获人脸的名字坐标 the positions of faces captured
    pos_name = (tuple([face.left(), int(face.bottom() + (face.bottom() - face.top())/4)]))

    # 对于某张人脸,遍历所有存储的人脸特征
    # For every faces detected, compare the faces in the database
    # 如果 person_X 数据不为空
    if str(cs_rd) != '0.0':
        e_distance_tmp = return_euclidean_distance(features_cap_arr, cs_rd)
        print(e_distance_tmp)
    else:
        # 空数据 person_X
        e_distance_tmp = 999999999
                            
    if e_distance_tmp < 0.4:
        name = dirList[m]
        print("May be person ")
        break
            
    else:
        print("Unknown person")
        continue

    # 矩形框
    # draw rectangle
    #下一行注释掉就可以没有矩形框
cv2.rectangle(img_rd, tuple([face.left(), face.top()]), tuple([face.right(), face.bottom()]), (0, 255, 255), 2)
#print('\n')

    # 写名字
    #下面(0,255,255)左边是字大小,右边是粗细
img = cv2.putText(img_rd, name, pos_name, font, 5, (0, 255, 255), 4, cv2.LINE_AA)
plt.imshow(img)
cv2.imwrite('./data/output.jpg',img)

   

最开始的是全程调用opencv摄像头,源码这应该还有,想要的话吱一声。