12月28日 OpenCV 实战基础学习笔记——疲劳检测

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前言

本文为12月28日 OpenCV 实战基础学习笔记——疲劳检测。

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一、眨眼疲劳检测

from scipy.spatial import distance as dist
from collections import OrderedDict
import dlib
import numpy as np
import cv2 as cv
import time
from google.colab.patches import cv2_imshow

FACIAL_LANDMARKS_68_IDXS = OrderedDict([
	("mouth", (48, 68)),
	("right_eyebrow", (17, 22)),
	("left_eyebrow", (22, 27)),
	("right_eye", (36, 42)),
	("left_eye", (42, 48)),
	("nose", (27, 36)),
	("jaw", (0, 17))
])

def eye_aspect_ratio(eye):
	# 计算距离，竖直的
	A = dist.euclidean(eye[1], eye[5])
	B = dist.euclidean(eye[2], eye[4])
	# 计算距离，水平的
	C = dist.euclidean(eye[0], eye[3])
	# ear值
	ear = (A + B) / (2.0 * C)
	return ear

# 设置判断参数
EYE_AR_THRESH = 0.3
EYE_AR_CONSEC_FRAMES = 3

# 初始化计数器
COUNTER = 0
TOTAL = 0

# 检测与定位工具
print("[INFO] loading facial landmark predictor...")
detector = dlib.get_frontal_face_detector()
predictor = dlib.shape_predictor('/content/drive/MyDrive/My_OpenCV_02/shape_predictor_68_face_landmarks.dat')

# 分别取两个眼睛区域
(lStart, lEnd) = FACIAL_LANDMARKS_68_IDXS["left_eye"]
(rStart, rEnd) = FACIAL_LANDMARKS_68_IDXS["right_eye"]

# 读取视频
print("[INFO] starting video stream thread...")
vs = cv.VideoCapture('/content/drive/MyDrive/My_OpenCV_02/test.mp4')
time.sleep(1.0)

def shape_to_np(shape, dtype="int"):
	# 创建68*2
	coords = np.zeros((shape.num_parts, 2), dtype=dtype)
	# 遍历每一个关键点
	# 得到坐标
	for i in range(0, shape.num_parts):
		coords[i] = (shape.part(i).x, shape.part(i).y)
	return coords

while True:
  # 预处理
  frame = vs.read()[1]
  if frame is None:
    break

  (h, w) = frame.shape[:2]
  width = 1200
  r = width / float(w)
  dim = (width, int(h * r))
  frame = cv.resize(frame, dim, interpolation=cv.INTER_AREA)
  gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)

  # 检测人脸
  rects = detector(gray, 0)

  for rect in rects:
    # 获取坐标
    shape = predictor(gray, rect)
    shape = shape_to_np(shape)

    # 分别计算ear值
    leftEye = shape[lStart:lEnd]
    rightEye = shape[rStart:rEnd]
    leftEAR = eye_aspect_ratio(leftEye)
    rightEAR = eye_aspect_ratio(rightEye)
  
    # 计算一个平均值
    ear = (leftEAR + rightEAR) / 2.0

    # 绘制眼睛区域
    leftEyeHull = cv.convexHull(leftEye)
    rightEyeHull = cv.convexHull(rightEye)
    cv.drawContours(frame, [leftEyeHull], -1, (0, 255, 0), 1)
    cv.drawContours(frame, [rightEyeHull], -1, (0, 255, 0), 1)
  
    # 检查是否满足阈值
    if ear < EYE_AR_THRESH:
      COUNTER += 1

    else:
      # 如果连续几帧都是闭眼的，总数算一次
      if COUNTER >= EYE_AR_CONSEC_FRAMES:
        TOTAL += 1

      # 重置
      COUNTER = 0

    # 显示
    cv.putText(frame, "Blinks: {}".format(TOTAL), (10, 30),
          cv.FONT_HERSHEY_SIMPLEX, 0.7, (0, 0, 255), 2)
    
    cv.putText(frame, "EAR: {:.2f}".format(ear), (300, 30),
          cv.FONT_HERSHEY_SIMPLEX, 0.7, (0, 0, 255), 2)
    
  cv2_imshow(frame)
  key = cv.waitKey(10) & 0xFF

  if key == 27:
    break

vs.release()
cv.destroyAllWindows()

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