Random Pan and Scan

You can use these expressions to randomly pan and scan a photo that is larger than your comp.

The expressions will automatically compensate for square pixels in a non-square pixel comp.

Import your image into the comp and add a point control to it.

Add the following expression to the point control:

scale_time=1;
hold_time=.5;
max_scale=200;

min_scale=Math.max(this_comp.width/width,this_comp.height/height)*100;
total_time=scale_time+hold_time
seed=Math.floor(time/total_time)+2;
seed_random(seed,true);
new_scale=random(min_scale,max_scale);
seed_random(seed-1,true);
old_scale=random(min_scale,max_scale);
[old_scale,new_scale];

Add the following expression for position:

scale_time=1;
hold_time=.5;

pix_factor=source.pixel_aspect/this_comp.pixel_aspect;
total_time=scale_time+hold_time;
seg_time=time%total_time;
old_scale=effect("Point Control").param("Point")[0];
new_scale=effect("Point Control").param("Point")[1];
seed=Math.floor(time/total_time)+2;
seed_random(seed,true);
max_x=(width/2)*(new_scale/100)*pix_factor;
min_x=this_comp.width-(width/2)*(new_scale/100)*pix_factor;
max_y=(height/2)*(new_scale/100);
min_y=this_comp.height-(height/2)*(new_scale/100);
new_pos=random([min_x,min_y],[max_x,max_y]);
seed_random(seed-1,true);
max_x=(width/2)*(old_scale/100)*pix_factor;
min_x=this_comp.width-(width/2)*(old_scale/100)*pix_factor;
max_y=(height/2)*(old_scale/100);
min_y=this_comp.height-(height/2)*(old_scale/100);
old_pos=random([min_x,min_y],[max_x,max_y]);
if(seg_time > scale_time){
  new_pos
}else{
  percent=seg_time/scale_time;
  ease(percent,old_pos,new_pos)
}

Add the following expression for scale:

scale_time=1;
hold_time=.5;

total_time=scale_time+hold_time;
seg_time=time%total_time;
old_scale=effect("Point Control").param("Point")[0];
new_scale=effect("Point Control").param("Point")[1];
if(seg_time > scale_time){
  [new_scale,new_scale]
}else{
  percent=seg_time/scale_time;
  ease(percent,[old_scale,old_scale],[new_scale,new_scale])
}

Adjust the scale time, hold time, and maximum scale to suit your needs. If you change the scale time or hold time, remember to do it in all three expressions.

back