仅从 OpenCV 的视频捕获中读取 mp4 文件的一部分

Question

I want to read only a part of mp4 file using Videocapture, this is my sample code to read whole mp4 in Videocapture object.

VideoCapture cap("demo.mp4");

Is it possible to read only a part of file ,ie from 10 seconds to 50 seconds. As the demo.mp4 is much big file so I don't want to load the remaining part in object which increases memory usage of program.

I also used cap.set(CAP_PROP_POS_FRAMES, start_frame); ,this works but it doesn't solve the memory usage issue.

Thank You

Answer 1

You could try to cut your video with ffmpeg before opening with VideoCapture . For example, to get 40 seconds fragment from 00:10 to 00:50, the command is

ffmpeg -i 'input.mp4' -ss '00:00:10' -t '00:00:40' output.mp4