Some simple advice from FB
FB just open-sourced : https://github.com/facebook/transform
It enables you to build a version of ffmpeg capable of transforming Equirectangular 360 video into a cubic map projection (Gnomonic) video.
If you've ever inspected the videos on Facebook which are 360 degree, you'll see they use this format. Also, I have found that when developing some Google Cardboard compatible apps for 360 cameras, that projecting a 'cube map' (or 'skybox') provides a better effect than the Equirectangular image on a sphere.