I have a real-time 30fps video, and I wish to convert it to a timelapse 30fps video so that each frame of the target video is the result of arithmetical mean of 10 original frames in a linear color-space. I thought of using the framerate filter, but it is designed to interpolates frames only when increasing the frame-rate. When I reduce the frame rate it simply drops some 9/10 of the frames resulting in jerky movement of fast moving objects instead of a nice smooth motion blur.
Any way to achieve this with the command-line ffmpeg?