• Adobe After Effects Expressions

  Random Jump Cuts based on time markers

  Posted by Rolando Lacanna on August 24, 2016 at 8:43 am

  Hello
  I’m trying to edit this expression:

  segDur = .5;// duration of each “segment” of random time
  minVal = inPoint;
  maxVal = outPoint – segDur;

  seed = Math.floor(time/segDur);
  segStart = seed*segDur;
  seedRandom(seed,true);
  startVal = random(minVal,maxVal);
  endVal = startVal + segDur;
  linear(time,segStart,segStart + segDur, startVal, endVal);

  To make the jump cuts start and end based on time markers, but with no luck 🙁
  Anyone has suggestions?
  Many thanks in advance

  segDur = .5;// duration of each "segment" of random time
minVal = inPoint;
maxVal = outPoint - segDur;

  seed = Math.floor(time/segDur);
segStart = seed*segDur;
seedRandom(seed,true);
startVal = random(minVal,maxVal);
endVal = startVal + segDur;
linear(time,segStart,segStart + segDur, startVal, endVal);

  Peter Zeet replied 6 years, 6 months ago 3 Members · 5 Replies
• 5 Replies

• 

  Dan Ebberts

  August 24, 2016 at 4:42 pm

  I guess it would be something like this:

  
minVal = inPoint;
maxVal = outPoint;
n = 0;
if (marker.numKeys > 0){
n = marker.nearestKey(time).index;
if (marker.key(n).time > time) n--;
}
if (n > 0){
t = time - marker.key(n).time;
seedRandom(n,true);
base = random(minVal,maxVal);
base + t;
}else
value


  but you’ll probably want to adjust maxVal so it never runs off the end of the clip.

  Dan
• 

  Rolando Lacanna

  August 24, 2016 at 8:54 pm

  That’s exactly what I was looking for!
  Thank you so much!!!
• 

  Peter Zeet

  January 29, 2020 at 6:14 pm

  hi!
  I’ve been trying to adapt it to make the jump go to the frame number on each marker’s comment instead of random (so if the marker comment says 17, it jumps to frame 17, etc), but no luck at all
  Any ideas? Thanks!
• 

  Dan Ebberts

  January 29, 2020 at 6:56 pm

  Try this:

  
n = 0;
if (marker.numKeys > 0){
n = marker.nearestKey(time).index;
if (marker.key(n).time > time) n--;
}
if (n > 0){
time - marker.key(n).time + framesToTime(parseInt(marker.key(n).comment,10));
}else
0


  Dan
• 

  Peter Zeet

  January 30, 2020 at 3:33 pm

  thanks!! what a beautiful line of code!

Reply to this Discussion! Login or Sign Up