• Adobe After Effects Expressions

  trying to hold frames of clip via expression

  Posted by Brian Kintz on September 20, 2010 at 2:01 pm

  Hi all,
  hoping someone can help…I’m trying to basically time remap a clip to hold on every frame for x amount of frames. In other words, I’d like each frame to hold for 15 frames, then 10 frames then 7 frames and so on until it plays real time. Does anyone know of an expression I can use to accomplish this? I’ve tried this, but can’t seem to get it right.

  Thanks!
  -brian

  animateon=15; //as in animate on 2's or 4's
framerate=(.5/thisComp.frameDuration)/animateon;
valueAtTime((Math.round(time*framerate))/framerate)

  Brian Kintz replied 15 years, 11 months ago 3 Members · 6 Replies
• 6 Replies

• 

  Kevin Camp

  September 21, 2010 at 3:57 pm

  i thnk it might be easier to just use time remapping and a key frame…

  enable time remapping and add a keyframe on the frame where you want the the realtime to start (this is relative to the clip, not the comp). so, if by frame 60 of the clip, you want it to be in realtime add a key at frame 60.

  then select the last two keyframes (the key you added and the last key) and position them so that the key you added will be at the comp time that you want the realtime to start. so, if you wanted the clip to be playing in realtime by 5 seconds, make sure that the key you added is aligned at 5 the second mark.

  if you wanted, you could use easy-ease on the keyframe that you added to make the transition smoother.

  just remember that if you adjust the timing of the second keyframe (the one you added) you will always need to adjust the last keyframe to maintain the realtime playback of the rest of the clip.

  Kevin Camp
  Senior Designer
  KCPQ, KMYQ & KRCW
• 

  Brian Kintz

  September 21, 2010 at 4:19 pm

  Thanks Kevin, I appreciate your suggestion. You may be misunderstanding what I’m trying to do (prob due to may lack of clear explanation). As opposed to a simple time remap & moving the keyframes to a specific point….I need the 1st frame (& only that frame) to hold for 15 frames, then the second frame to hold for 15 frames. So in essence I need an automated way to tell each frame of a clip to hold for (X) # of frames. As the clip goes on, the duration of how long each frame will decrease 15, 10,7,5,3,realtime (or a sequence similar to this). Yes this can be done by manually placing a timeremap/hold keyframe on each frame….but what a time consuming pain that is.
  Thanks agin Kevin….any other ideas?

  Brian Kintz
  Art Director
  Starz Entertainment
  720.852.3283
• 

  Chris Wright

  September 21, 2010 at 11:03 pm

  something that starts off like this..

  hold for 15 frames then a simply counter to count 15 frames then reduce to 10 frames, the counter’s loop amount gets reset too.

  framesToTime(Math.floor(timeToFrames()/15));

  https://technicolorsoftware.hostzi.com/
• 

  Brian Kintz

  September 21, 2010 at 11:55 pm

  Thanks Chris, that’s getting closer!

  Brian Kintz
  Art Director
  Starz Entertainment
  720.852.3283
• 

  Chris Wright

  September 22, 2010 at 3:37 am

  the expression uses a weird exponential forumula so a linear function will not work.

  a simple way is use effect posterizetime with a keyframed slider. I’ll see if I can make an expression though…
• 

  Brian Kintz

  September 25, 2010 at 2:55 am

  Thanks Chris,
  If you get anything please respond back. For now I’m basically bringing in the same clip 6 or so times and giving it a different frame rate for each instance of the clip. I figure this way I can sequence the clips together and slip the in/out points around to emulate a flipbook-like style when the clip plays

  Thanks again, keep me posted

  Brian Kintz
  Art Director
  Starz Entertainment
  720.852.3283

Reply to this Discussion! Login or Sign Up