从视频帧中采样并将它们保存为图像 - python openCV

Question

我有一个视频文件，我知道如何保存所有帧，但我的问题是如何仅将每 20 帧中的一帧保存为图像？谢谢。

Answer 1

这是基于本教程： https://theailearner.com/2018/10/15/extracting-and-saving-video-frames-using-opencv-python/

import cv2
# Opens the Video file
cap= cv2.VideoCapture('C:/New/Videos/Play.mp4')
i=0
while(cap.isOpened()):
ret, frame = cap.read()
if ret == False:
break
if i % 20 == 0: # this is the line I added to make it only save one frame every 20
cv2.imwrite('kang'+str(i)+'.jpg',frame)
i+=1
cap.release()
cv2.destroyAllWindows()

Answer 2

或者尝试使用除法：

import cv2
capture = cv2.VideoCapture('C:/New/Videos/Play.mp4')
c=0
while capture.isOpened():
r, f = capture.read()
if r == False:
break
if c / 20 == c // 20:
cv2.imwrite('kang'+str(c)+'.jpg',frame)
c+=1
capture.release()
cv2.destroyAllWindows()