中文说明：该程序实现将视频文件按照帧数转化为图片文件，并保存在文件夹中，该程序可以实现将视频信号转化为图片信号。按帧数实现对视频信号的提取。
English Description：
The program can convert video files into picture files according to the number of frames and save them in the folder. The program can convert video signals into picture signals. The video signal is extracted according to the number of frames.