Пульс по вебкамере

heartbeat.py

# https://habr.com/ru/post/517424/

import cv2
import io
import time
import numpy as np
from matplotlib import pyplot as plt
 


cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1920)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 1080)
cap.set(cv2.CAP_PROP_FPS, 30)

x, y, w, h = 800, 500, 100, 100
heartbeat_count = 128
heartbeat_values = [0] * heartbeat_count
heartbeat_times = [time.time()] * heartbeat_count

fig = plt.figure()
ax = fig.add_subplot()


while(True): 
    ret, frame = cap.read()

    # Our operations on the frame come here
    img = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

    crop_img = img[y:y + h, x:x + w]
    window_name = 'image'
    
    heartbeat_values = heartbeat_values[1:] + [np.average(crop_img)]
    heartbeat_times = heartbeat_times[1:] + [time.time()]

    ax.plot(heartbeat_times, heartbeat_values)
    fig.canvas.draw()
    plot_img_np = np.fromstring(fig.canvas.tostring_rgb(), dtype=np.uint8, sep='')
    plot_img_np = plot_img_np.reshape(fig.canvas.get_width_height()[::-1] + (3,))
    plt.cla()

    # Display the frame
    cv2.imshow('Crop', crop_img)
    cv2.imshow('Graph', plot_img_np)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()