need AUDIO to control SCALE

[Rutger]

Quentin,

Instead of trying to copy and paste keyframes, I would suggest adding a simple expression to the Scale property. Simply use the pickwhip to link the Scale to the “Both Channels” slider on the Audio Amplitude layer that was created when you converted audio to Keyframes.

It will write the following code for you:

temp = thisComp.layer(“Audio Amplitude”).effect(“Both Channels”)(“Slider”);
[temp,temp]

Since Scale on a 2D layer has two dimensions (width and height), the audio amplitude ion the example determines both. To get variations on the theme, simply change the second line to for instance [temp, temp*temp] or [temp, temp*2]. This way the variations in height will be more dramatic than the variations in width. If you just use some basic math you should be able to get the effect you want.

For more powerful control of audio keyframes have a look at Soundkeys by Trapcode.

Hope that helps,

Rutger

[Quentin Block]

Thanks, Rutger.
This was helpful, as I have not really used expressions before and it’s great to start.
However, the range is very limited when scaling the object using the Audio Amplitude. I guess it

[Mylenium]

Use something like this:

ref_amp=thisComp.layer(“Audio Amplitude”).effect(“Both Channels”)(“Slider”); //reference layer
max_amp=100; //fill in maximum amplitude from reference layer
min_amp=100; //fill in minimum amplitude from reference layer
max_scale_X=100; //maximum allowed scale X
min_scale_X=0; //minimum allowed scale X
max_scale_Y=100; //maximum allowed scale Y
min_scale_Y=0; //minimum allowed scale Y

X=linear(ref_amp,min_amp,max_amp,min_scale_X,max_scale_X);
Y=linear(ref_amp,min_amp,max_amp,min_scale_Y,max_scale_Y);

[X,Y]

Mylenium

[Pour Myl

[Quentin Block]

Hey Mylenium.
This is great!
I have only played around with it a bit, but it

[Iancorey]

One of the tricks that I have used when the audio keyframes don’t transform the layer sufficiently is create an “animation only soundtrack”. I can pump the levels really high, render to .aiff, import, convert to keyframes and pickwhip. I can even use JUST the lower (bass) frequencies by placing a lowpass, rendering an .aiff, importing it, converting, pickwhipping. This is handy for using kickdrum thumps to force something to scale.

I just have to be sure to mute that “animation only soundtrack” layer or render the movie without sound if my soundmix is done elsewhere.

I have Soundkeys now (and it r0xorz), so I haven’t done this in a while.