View Full Version : sound driven effect?

10 October 2002, 12:21 AM
Is there a way to control the opacity
or blur effect on a layer with a sound?
(a heart beat)

10 October 2002, 03:57 AM
yep. if you have the PB version you can use motion math.

just add motion math (under animation>keyframe assistant) to the layer whose opacity you are effecting.

then on the pop-up window choose "load" and load the "" file.

you'll see two rows and three columns. in the first row selesct your layer and the opacity property.

on the second row select the audio layer. then in the script window set your min and max values at the bottom. it will bake keyframes for the whole thing.:)

if you are using the standard bundle there is probably a way to do it using expressions. look at for a possible tut.

Ian Jones
10 October 2002, 08:46 AM
Thx for the tip!

I just tried it and it seems to take a ridiculous amount of time to render... for about 30 seconds of the music and one layer being blurred by motion math control Comp size: 640*480 it was taking about 1 minute per frame! whats up with that? The samplerate mybe? of the MM?

10 October 2002, 03:41 PM
bizarre. i couldn't tell you why it was taking so long to render. did you try clearing your image cache before rendering? also, did you close the composition window? it takes more ram to display your comp while its rendering.

my suggestion would be to see if you can do anything via the expression route since it won't set keyframes every frame, OR

since it's only a hart beat you could very easily do it maually by twirling down the audio and looking at the wave form. if the heartbeat is fairly regular then you'd only have to set the keyframes once then just copy and paste down the timeline.

if you do find a way to do it with expressions please pot it here! i'd be interested to see what you come up with.:)

10 October 2002, 06:33 PM
You should check out the sound keys plug in from TRAPCODE.

It should be alot faster than Motion Math and it offers more control.

10 October 2002, 11:12 PM
nice plugin.

shine rules too.

thanks for the info!

10 October 2002, 01:13 PM
yeah, soundkeys is absolutely rockin. cheap too!!! trapcode need to do more plugins! never tried to use motion math tho so will give it a shot now!!

10 October 2002, 10:42 PM
yeah! trapcode its very nice, they only have 3 plugins, and the 3 plugins are the best, i have purchase shine, and i will buy another plugins... it's so sheep


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