backward and forward flows

[bolianchen]

Dear authors

I was wondering how you obtain the backward flow of the first frame and the forward flow of the last frame in a scene.
Ex: there are 000.jpg, 001.jpg, 002.jpg in a scene
000.jpg, 001.jpg => forward_000.flo
(no -001.jpg to compute backward_000.flo)
001.jpg, 002.jpg => forward_001.flo
001.jpg, 000.jpg => backward_001.flo
002.jpg, 001.jpg => backward_002.flo
(no 003.jpg to compute backward_002.flo)

Thank you very much.

Best,
Bolian

[bolianchen]

Dear authors

I just noticed the number of images in a scene is one less than the numbers of either forward or backward flows.
With the same example (000.jpg, 001.jpg, 002.jpg in a scene), do you obtain the optical flows as follows?
000.jpg, 001.jpg => forward_000.flo
001.jpg, 000.jpg => backward_000.flo
001.jpg, 002.jpg => forward_001.flo
002.jpg, 001.jpg => backward_001.flo

Thanks.
Best,
Bolian