[FFmpeg-user] Read values from a text or CSV file?

[Michael Koch]

Hello all,

for a special effect I want to overlay a small video over the main 
video, where the position of the overlay is a function of time. It's a 
complicated function and can't be expressed by a simple formula. 
Segment-wise linear interpolation might work, but many segments are 
required and the command line may get too long:

between(t,0,1) * lerp(x0,x1,t) +
between(t,1,2) * lerp(x1,x2,t-1) +
between(t,2,3) * lerp(x2,x1,t-2) + ...

Is there any way to read the pre-calculated coordinates for the overlay 
filter from a text or CSV file? Or from a PGM file, as in the remap filter?

Thanks,
Michael