Mirrored difference mode for lane centering diagnostics

[simontheflutist]

This is a feature request for the following video postprocessing: given a frame X, return X.roll_compensate() - X.roll_compensate().mirror_left_right(), possibly with rescaling/s-curve postprocessing to look more appealing. (roll_compensate brings the frame into calibrated view)

The reason is to provide an instant visual diagnostic for lane centering accuracy on straight roads. If the Comma is perfectly centered in the lane, the left and right lanelines should overlap. Moreover, because the formula incorporates differencing, the parity of non-overlaps shows whether the car is left or right of center.

[nelsonjchen]

This would probably require some script or something to get stuff out of the rlogs. Maybe ffmpeg can take an input from some external processing script to do this.

[nelsonjchen]

If you can provide a simple proof of concept script to do this, let me know. I wrote this project in a way that dances outside of comma's codebase. Going in is quite a step though.