extract_frame.py

import os


all_videos = ('archery', 
              'breaststroke', 
              'crossbow', 
              'dance', 
              'dodge', 
              'fly', 
              'horse_riding', 
              'run', 
              'skydiving',
              'waving_weapon')

ucf_videos = ('archery',
              'horse_riding', 
              'run', 
              'breaststroke', 
              'skydiving')

new_videos = ('crossbow', 
              'dance', 
              'dodge', 
              'fly', 
              'waving_weapon')


def process_videos(video_list=all_videos):
    if not os.path.exists('./frames'):
        os.makedirs('./frames')

    for video in video_list:
        if os.path.exists('./' + video):
            for i in range(1, 11):
                video_name = './' + video + '/' + video + '_' + str(i) + '.mp4'
                destination = './frames/' + video + '_'
                get_frame(video_name, destination)


def get_frame(video, directory):
    """
    extract frames from videos with given FPS 15
    """

    fps = '20'
    dest = video[-5:-4]  # The folder that the frame images will end up in
    os.system('ffmpeg -i ' + video + ' -vf scale=240:240' + ' -r ' + fps + ' ' + directory + dest + '_%03d.png')


def main():
    process_videos()


if __name__ == '__main__':
    main()