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希望通过cv2.VideoCapture类截取视频帧图片，期间只能截取视频的每帧图片，不能跳帧截取图片，原来是在读取视频帧的时候没有写入ret, frame = cv2.VideoCapture.read()。

ret, frame = cv2.VideoCapture.read()函数输出的是两个参数,第一个参数ret 为True 或者False,代表有没有读取到图片；第二个参数frame表示截取到一帧的图片。

修改前代码（只能逐帧逐帧截取视频帧图片）：

import cv2

import os

def save_img():

video_path = r’你的视频绝对路径’

videos = os.listdir(video_path)

for video_name in videos:

file_name = video_name.split(‘.’)[0]

folder_name =  file_name

os.makedirs(folder_name,exist_ok=True)

vc = cv2.VideoCapture(video_path+video_name) #读入视频文件

c = 1

if vc.isOpened():  # 判断是否正常打开

rval, frame = vc.read()

else:

rval = False

timeF = 300  # 视频帧计数间隔频率

while rval:  # 循环读取视频帧

pic_path = folder_name + ‘/’

if (c % timeF == 0):  # 每隔timeF帧进行存储操作

cv2.imwrite(pic_path + file_name + ‘_’ + str(c) + ‘.jpg’, frame)#存储图像

c = c + 1

cv2.waitKey(1)

vc.release()

save_img()

修改后代码（能够跳帧截取视频帧）：

import cv2

import os

def save_img():

video_path = r’D:\python3-PycharmProjects1\video2picture\20180911-12-48-31\data\123/’

videos = os.listdir(video_path)

for video_name in videos:

file_name = video_name.split(‘.’)[0]

folder_name =  file_name

os.makedirs(folder_name,exist_ok=True)

vc = cv2.VideoCapture(video_path+video_name) #读入视频文件

c = 1

if vc.isOpened():  # 判断是否正常打开

rval, frame = vc.read()

else:

rval = False

timeF = 300  # 视频帧计数间隔频率

while rval:  # 循环读取视频帧

rval, frame = vc.read()

pic_path = folder_name + ‘/’

if (c % timeF == 0):  # 每隔timeF帧进行存储操作

cv2.imwrite(pic_path + file_name + ‘_’ + str(c) + ‘.jpg’, frame)  # 存储为图像,保存名为 文件夹名_数字（第几个文件）.jpg

c = c + 1

cv2.waitKey(1)

vc.release()

save_img()