Full HD video playback at variable speed

i am working on an installation where i need to play back a fullHD video file. The playback speed is controlled by an bicycle speed sensor.
my current results are not very promising , i get stuttering playback esp. if playback speed is getting above 2times of the original framerate.

are there experts around that could advise me in finding the right codec / playback method for this purpose?

many thanks,

Make it an image sequence and use Player (EX9.texture Timebased) if you need it in DX9 or FileTexture (DX11 2d.pooled) if you need it in DX11 use DDS textures for better speed and less GPU memory usage