ffmpeg从视频中截取图像帧

1、普通抽帧

linux_commod = 'ffmpeg -i {:} -r 15 -f image2 {:}/%07d.jpg'.format(video_input, frame_output)

2、高清抽帧

    linux_commod = 'ffmpeg -i {:} -f image2  -vf fps=fps=15 -qscale:v 2 {:}/%07d.jpg'.format(video_input, frame_output)

3、python多线程高清ffmpeg抽帧实例

import subprocess
import os
import threading
import pdb
import copy

VIDEO_EXTENSIONS = ['mp4', 'webm', 'avi']

def main(video_dir, frame_dir, n_thread):
    print('Starting: convert videos into frames\nvideo_dir: {:}\tframe_dir: {:}'.format(video_dir, frame_dir))
    threads = []
    for root, dirs, files in os.walk(video_dir):
        for file_name in files:
            if is_video_file(file_name):
                video_name = os.path.join(root, file_name)
                frame_output_path = os.path.splitext(video_name.replace(video_dir, frame_dir))[0]
                makefile(frame_output_path)
                threads.append(threadFun(video2frame, (video_name, frame_output_path )))
                
    run_threads(threads, n_thread)
    print('all threads is finished')    

def is_video_file(filename):
    return any(filename.endswith(extension) for extension in VIDEO_EXTENSIONS)

def makefile(file_dir):
    if not os.path.exists(file_dir):
        os.makedirs(file_dir)
        
def run_threads(threads, n_thread):
    used_thread = []
    for num, new_thread in enumerate(threads):
        print('thread index: {:}'.format(num), end=' \t')
        new_thread.start()
        used_thread.append(new_thread)
        
        if num % n_thread == 0:
            for old_thread in used_thread:
                old_thread.join()
            used_thread = []    
def video2frame(video_input, frame_output):
   # linux_commod = 'ffmpeg -i {:} -r 15 -f image2 {:}/%07d.jpg'.format(video_input, frame_output)
    linux_commod = 'ffmpeg -i {:} -f image2  -vf fps=fps=15 -qscale:v 2 {:}/%07d.jpg'.format(video_input, frame_output)
    print('{:}'.format(video_input))
    subprocess.getstatusoutput(linux_commod)
    
class threadFun(threading.Thread):
    def __init__(self, func, args):
        super(threadFun, self).__init__()
        self.fun = func
        self.args = args
    def run(self):
        self.fun(*self.args)

if __name__ == '__main__':
    video_dir_train ='/xxx/xxx/data'
    frame_dir_train = '/xxx/xxx/xxx'
    main(video_dir_train, frame_dir_train, n_thread =20)