Video speed react to audio?


#1

Hello,

I am trying to make my environment react to sound using the MoGraph Audio Effector. I already know how to affect it to light intensity for example, but I would like the sound to be affected to the video speed.

Here is an example : https://youtu.be/VGv2x6mE5pc?t=52

I am new to C4D. Any help would be appreciated

Thank you, have a good day :slight_smile:


#2

I have no idea what you want to do.

What do you mean by “video speed”? There is a frame rate (like 30 frames/sec) that is a constant. There is an animation speed that depends on your set keys, or on a time track to modify that key set. And there are speeds regarding many animated shaders.

If you really want to speed up the rendered animation, that sounds more like a task for After Effects as a post effect.


#3

Hi there,

I’m sure this is possible in After Effects but in the past I have done it with Apple Motion. There is a behaviour called ‘Scrub’ that imitates the effect of scrubbing forward and backward through your video clip. This behaviour can be driven by an ‘Audio’ parameter behaviour loaded with your sound clip. When combined you get an effect where increases in sound levels speed up your video clip.


#4

If you read through this great article by After Effects master Dan Ebberts you’ll find an example of what you want to do at the bottom - the tram video.

Perhaps you can either use the same coding principle in C4D - or just use Dan’s expression to do some work in AE.


#5

If i understand correctly, by video speed you are meaning the speed of your animation

You might be able do this within Cinema by using the time track (which is a special animation track). this video gives a good overview on how to use it.

Unfortunately i can’t find a way to drive the time track (once it is set up) from an external parameter. All i can seem to do is edit its FCurve. maybe someone else knows how to do that though.


#6

Thank you for you answers,

I understand that I didn’t express myself well enough for you to know what i’m looking for, so here is a great example for what I am trying to achieve :

https://youtu.be/VGv2x6mE5pc?t=52

The “video speed” I was referring to is actually the camera movement that should react to the sound (move faster).
The reason why I can’t do that in AE is because I also have lighting effects that react to the sound.


#7

You can get a value for sound level from sound effector, and add a small % of this to an align to spline position every frame, so camera speed is proportional to volume. This file is from R20, and sound effector needs a fall off field to work - earlier C4D versions differ.

https://www.dropbox.com/s/58l8y89qjn5bcaj/camspeed2.zip?dl=1


#8

Thank you a lot! This is exactly what I was trying to do.

Now I am trying to figure out how everything is connected to do the same on a spiral and add a minimum speed to the camera > 0.


#9

To add a constant baseline speed, introduce a math add right after sample strength. Add a low value - something like 0.05.