Question

我已经使用来自opencv while循环的数据成功创建了动画图。从背景中减去相机上的运动，创建白色像素，将这些像素平均average_int，然后使用matplotlib FuncAnimation()函数在y轴上进行绘制。

问题是，我想使用该程序进行研究，并且图形处理使视频滞后太多，因此需要对其进行优化。本来应该使用blitting技术将处理速度提高10倍，但是每当我尝试在FuncAnimation(blit=True)中使用它时，都不会提高性能，并且图表会不断闪烁，并且永远不会正确绘制图表。我似乎找不到问题。我以为Matplotlib窗口可能以某种方式干扰了opencv窗口。

import numpy as np
import cv2
import matplotlib.pyplot as plt
import matplotlib.animation as animation
from scipy import signal

cap = cv2.VideoCapture(0)

_, first_frame = cap.read()

count = 0
peaks_frames = 1
peaks_diff = [1]
result_array = np.array([])

x_len = 60
x_len2 = 200
y_range = [-2, 100]
y2_range = [3, 12]

fig = plt.figure()
ax = fig.add_subplot(2,1,1)
ax2 = fig.add_subplot(2,1,2)

xs = list(range(0,60))
xs2 = list(range(0,200))
ys = [0] * x_len
ys2 = [0] * x_len2

line, = ax.plot(xs, ys, 'k')
line2, = ax2.plot(xs2, ys2,'b')

ax.set_ylim(y_range)
ax2.set_ylim(y2_range)


def animate(i, ys, ys2):
   ys.append(average_int)
    ys = ys[-x_len:]
    line.set_ydata(ys)

    ys2.append(peaks_frames)
    ys2 = ys2[-x_len2:]
    line2.set_ydata(ys2)
    return line, line2

ani = animation.FuncAnimation(fig, animate, fargs=(ys, ys2),interval=120, blit=True)

while True:

    ret, frame = cap.read( )

    difference = cv2.absdiff(first_frame, frame)
    difference = cv2.GaussianBlur(difference, (3, 3), 0)

    _, difference = cv2.threshold(difference, 18, 255, cv2.THRESH_BINARY)


    cv2.imshow('first frame (1)', first_frame)
    cv2.imshow('Original', frame)
    cv2.imshow('difference', difference)

    average = (np.average(difference))                                  
    average_int = int(average)                                          

    result_array = np.append(result_array, average_int)                 

    peaks_pos = signal.find_peaks_cwt(result_array, range(1,2,10))      

    peaks_diff = peaks_pos[1:] - peaks_pos[:-1]                         

    count = count + 1

    if count >= 30:                                                     
        peaks_frames = peaks_diff[-1]


    plt.pause(0.000001)


    key = cv2.waitKey(30) & 0xff
    if key == 27:
        break

cap.release()
cv2.destroyAllWindows()

我的动画图不允许我使用blitting技术

0 个答案: