• Adobe After Effects Expressions

  Sound Keys Time Remap Interpolation?

  Posted by Michael Carlson on November 28, 2009 at 10:15 pm

  Howdy COWers,

  I have researched this question fairly fully, and hope that I am not replicating a question (if I am, my apologies).

  I am taking 60 frame footage of someone tapping a drum and am Time Remapping that video to ramp into place as the drum stick hits the drum. I’ve met with both success and failure.

  I am currently (successfully) using Trapcode Sound Keys to locate a specific note; the range placement is generating outputs between 0.0 and 1.0. I am then remapping the time to the (adjusted) correct frame when the appropriate threshold has been met (.9) using these expressions:

  x = time*2.5;
  y = value;
  if ( thisComp.layer(“Black Solid 2”).effect(“Sound Keys”)(“Output 1”) > .9) {value = x} else {value =y};

  This creates an interesting motif, to be sure, but the incorrect one.

  Of course, the remapped time reverts back the timeline whenever the threshold is below .9; the desired effect would be for the video to freeze and/or interpolate between these ramped moments.

  My assumption is that I require an intermediary (a slider, perhaps?) to reference, but have not been able to wrap my brain around it yet.

  Any thoughts out there?

  MC

  x = time*2.5;
y = value;
if ( thisComp.layer("Black Solid 2").effect("Sound Keys")("Output 1") > .9) {value = x} else {value =y};

  Michael Carlson replied 16 years, 5 months ago 2 Members · 2 Replies
• 2 Replies

• 

  Dan Ebberts

  November 28, 2009 at 10:44 pm

  Have you tried setting the Range Falloff to None(integrate)? I think that will get you closer to what you’re after.

  Dan
• 

  Michael Carlson

  November 28, 2009 at 11:39 pm

  Hey Dan,

  Thanks for the quick reply. It does play continuously but neuters any ramping (video essentially plays through at 2.5x; the change mitigates the previous effect).

  What do you think of interpolation? Would it be possible, in your opinion, to use take Trap Code key frames, to boil up the appropriate key values via an if statement, and then interpolate those frames via an expression?

  I am, admittedly, not very familiar with ease(t, value 1, value 2), etc.

  Many many thanks.

  Michael

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