Hi, does anyone know how to take an image sequence and for each frame, set each pixel value to that pixel's max value over all of the previous frames?

For example, on frame 25 out of 50, each pixel would be set it its respective max over the range 1-25

Thanks!

You can do it with VEX. See the “timefilter” node and take a look at the vex function, within the for loop. You could reproduce the functionality within a VOP COP.

I'm not sure how fast it is to do it this way, though it would probably be faster than doing it in a python COP.

You can do it with VEX. See the “timefilter” node and take a look at the vex function, within the for loop. You could reproduce the functionality within a VOP COP.

I'm not sure how fast it is to do it this way, though it would probably be faster than doing it in a python COP.

Thanks for the reply - how do I access the previous frame from within VOP COP?

Hi,

You can use something like this:

vector current = cinput ( 0, PL, AI, IX, IY, F );
if ( F > 1 )
{
for ( int i = 1; i < F; ++i )
{
vector prev = cinput ( 0, PL, AI, IX, IY, i );
current = max ( current, prev );
}
assign ( Cr, Cg, Cb, current );
}

Either paste inside Inline Code VOP or Snippet VOP. If you want to prototype more conveniently, you can also use the Inline VEX Filter COP here:
https://www.orbolt.com/asset/animatrix::inlineVexFilter::1.00 [orbolt.com]

Thanks Pusat - works very well