For anyone using Circuit Tools to analyze laps, RaceChrono has excellent support for exporting data to its VBO file format.
But plenty of people here and in other forums have asked how to integrate external video. Using video along with the GPS data is a big benefit - you can confirm actual position on the track to often greater accuracy than the GPS info. Plus you can see steering wheel position, foot pedals, or other info, depending on where you mount cameras.
No lap timer that I'm aware of has yet provided the ability to automatically link video during VBO export, but Antti and I have discussed it and a solution might find its way into a future version of RaceChrono. In the meantime I am releasing my findings on how to manually link external video to Circuit Tools. I welcome any feedback.
VBO File Reverse Engineering for External Video.dochttps://drive.google.com/file/d/0Bw0_gq98C4bvX2k1NXFZcFFFeDQ/view?usp=sharing