环境
- windows 10 64bit
- mediapipe 0.8.10.1
前言
本文使用 google 家的 mediapipe 机器学习框架，结合 opencv 和 numpy，实现了一个实时识别 站立、坐下、走动、挥手 共4个动作的简单系统。
mediapipe 能做的事情非常多，感兴趣的童鞋可以去研究研究。
代码实践
首先，需要安装 mediapipe
pip install -U mediapipe接着，来看代码，部分加了注释
import cv2
import mediapipe as mp
import numpy as np
def calculate_angle(a, b, c):
'''
计算角度
:param a:
:param b:
:param c:
:return:
'''
a = np.array(a)
b = np.array(b)
c = np.array(c)
radians = np.arctan2(c[1] - b[1], c[0] - b[0]) - np.arctan2(a[1] - b[1], a[0] - b[0])
angle = np.abs(radians * 180.0 / np.pi)
if angle > 180.0:
angle = 360 - angle
return angle
def calculate_dist(a, b):
'''
计算欧式距离
:param a:
:param b:
:return:
'''
a = np.array(a)
b = np.array(b)
dist = np.linalg.norm(a - b)
return dist
if __name__ == '__main__':
mp_drawing = mp.solutions.drawing_utils
mp_pose = mp.solutions.pose
cap = cv2.VideoCapture('liuruoying.mp4')
# 分辨率
frame_width = int(cap.get(3))
frame_height = int(cap.get(4))
# 保存结果视频
out = cv2.VideoWriter("result.mp4", cv2.VideoWriter_fourcc(*'mp4v'), 30, (frame_width, frame_height))
counter = 0
stage = None
with mp_pose.Pose(min_detection_confidence=0.3, min_tracking_confidence=0.8) as pose:
while cap.isOpened():
ret, frame = cap.read()
if not ret:
break
# 转换下颜色空间
image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
# 这里设置为不可写
image.flags.writeable = False
# 检测
results = pose.process(image)
# 这里设置为可写，颜色也转换回去
image.flags.writeable = True
image = cv2.cvtColor(image, cv2.COLOR_RGB2BGR)
# 提取关键点
try:
landmarks = results.pose_landmarks.landmark
# 获取相应关键点的坐标
lshoulder = [landmarks[mp_pose.PoseLandmark.LEFT_SHOULDER.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_SHOULDER.value].y]
lelbow = [landmarks[mp_pose.PoseLandmark.LEFT_ELBOW.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_ELBOW.value].y]
lwrist = [landmarks[mp_pose.PoseLandmark.LEFT_WRIST.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_WRIST.value].y]
lhip = [landmarks[mp_pose.PoseLandmark.LEFT_HIP.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_HIP.value].y]
lankle = [landmarks[mp_pose.PoseLandmark.LEFT_ANKLE.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_ANKLE.value].y]
lknee = [landmarks[mp_pose.PoseLandmark.LEFT_KNEE.value].x,
landmarks[mp_pose.PoseLandmark.LEFT_KNEE.value].y]
rshoulder = [landmarks[mp_pose.PoseLandmark.RIGHT_SHOULDER.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_SHOULDER.value].y]
relbow = [landmarks[mp_pose.PoseLandmark.RIGHT_ELBOW.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_ELBOW.value].y]
rwrist = [landmarks[mp_pose.PoseLandmark.RIGHT_WRIST.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_WRIST.value].y]
rhip = [landmarks[mp_pose.PoseLandmark.RIGHT_HIP.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_HIP.value].y]
rankle = [landmarks[mp_pose.PoseLandmark.RIGHT_ANKLE.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_ANKLE.value].y]
rknee = [landmarks[mp_pose.PoseLandmark.RIGHT_KNEE.value].x,
landmarks[mp_pose.PoseLandmark.RIGHT_KNEE.value].y]
# 计算角度
langle = calculate_angle(lshoulder, lelbow, lwrist)
rangle = calculate_angle(rshoulder, relbow, rwrist)
lsangle = calculate_angle(lhip, lshoulder, lelbow)
rsangle = calculate_angle(rhip, rshoulder, relbow)
ankdist = calculate_dist(lankle, rankle)
rwdist = calculate_dist(rhip, rwrist)
lwdist = calculate_dist(lhip, lwrist)
rhangle = calculate_angle(rshoulder, rhip, rknee)
lhangle = calculate_angle(lshoulder, lhip, lknee)
rkangle = calculate_angle(rankle, rknee, rhip)
lkangle = calculate_angle(lankle, lknee, lhip)
# 这块是具体的业务逻辑，各个数值，可根据自己实际情况适当调整
if ((rhangle > 80 and lhangle > 80) and (rhangle < 110 and lhangle < 110) and (
lkangle < 100 and rkangle < 100)):
stage = 'sitting'
elif (langle < 160 and langle > 40) or (rangle < 160 and rangle > 40):
if ((lsangle > 20 or rsangle > 20) and (lwdist > 0.3 or rwdist > 0.3)):
stage = "wave"
elif ((ankdist > 0.084) and (langle > 150) and (rangle > 150)):
counter += 1
if counter > 1:
stage = 'walking'
else:
stage = 'standing'
counter = 0
except:
pass
cv2.rectangle(image, (0, 0), (225, 73), (245, 117, 16), -1)
cv2.putText(image, 'STAGE', (65, 12), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 0), 1, cv2.LINE_AA)
cv2.putText(image, stage, (60, 60), cv2.FONT_HERSHEY_SIMPLEX, 2, (255, 255, 255), 2, cv2.LINE_AA)
# 画骨骼关键点
mp_drawing.draw_landmarks(image, results.pose_landmarks, mp_pose.POSE_CONNECTIONS,
mp_drawing.DrawingSpec(color=(245, 117, 66), thickness=2, circle_radius=2),
mp_drawing.DrawingSpec(color=(245, 66, 230), thickness=2, circle_radius=2)
)
# 显示结果帧
cv2.imshow('mediapipe demo', image)
# 保存结果帧
out.write(image)
# 按q退出
if cv2.waitKey(10) & 0xFF == ord('q'):
break
# 资源释放
cap.release()
cv2.destroyAllWindows()
