That's true, I hacked the rear view camera of my car to draw guide lines connected to the wheel position using a pi[1], but it took me tons of effort to reverse

That's true, I hacked the rear view camera of my car to draw guide lines connected to the wheel position using a pi[1], but it took me tons of effort to reverse engineer the wiring system and CANBUS of my car, I learned a lot (CANBUS is a lot of fun:P), but I don't want that level of involvement here. But I'd like something easier to work with, the "data accessible on the filesystem" of the Garmin seems to be the perfect balance between effort and "hackability". [1]: https://github.com/kuon/backup-camera https://github.com/kuon/backup-camera