Firefly media types: raw video bitmaps vs ordinary firefly bitmaps.

I have a prerecorded video clip that I'd like to run through the 'optical flow' component to generate an extra layer for my video.

using the 'video player' as the input for the 'optical flow' component makes the outcome appear bumpy because the video starts to skip frames due to computing power. at the same time it isn't important for me to have the frames processed in real time as I'd anyway like to export the output frames and animate them in a different program to get a smooth result. I just haven't found out how to run the video in firefly in such a way that it would rather slow down than skip the frames to keep the original speed. I've tried using the image sequence of the according video frames as an alternative, but 'optical flow' component only seems to accept 'raw video bitmap' input. is there any way to transfer a sequence of ordinary 'firefly bitmaps' into 'raw video bitmaps'?

or is there any other way to feed the 'optical flow' component with a prerecorded video file in such a way that frames wouldn't get skipped?

I'd be grateful for any suggestions,

best,
jo