Reading that paper (Vass and Perlaki), they present a very good solution. If you're running the inverse transformation on a sequence of frames, all of which have the same distortion parameters, then just compute the inverse transformation once ("slow"), and cache the result. Then do a look-up using either exact values or some kind of fast interpolation for all of your movie frames.
They also describe using Newton's method to compute the (xd, yd) => (x,y) transformation, as I suggested. Since these guys have already looked at this problem, I suspect that the algebraic inverse transformation is probably very long and painful. Even if your distortion parameters are varying, you could also speed up the process by using the solution from the previous frame as the staring point for your Newton iteration of the next frame. On Mon, Apr 16, 2012 at 4:06 PM, Dan Eicher <d...@trollwerks.org> wrote: > >> These guys describe a fast preview mode (if that's the problem): >> >> http://www.vassg.hu/pdf/vass_gg_2003_lo.pdf >> >> ...not that I understand the math behind it. >> >> Dan >> _______________________________________________ >> Bf-committers mailing list >> Bf-committers@blender.org >> http://lists.blender.org/mailman/listinfo/bf-committers >> > > _______________________________________________ Bf-committers mailing list Bf-committers@blender.org http://lists.blender.org/mailman/listinfo/bf-committers