Audio Driven Animation? (Count Beats)

[Atom]

Hello All,

 

I am a new Houdini Indie user and I want to control animation from music. I have watched Peter Quints Chops Animation Tutorial and it no longer works with version Houdini version 13. For the final step chan0 is never present. (It could be operator error, my fault but I have followed the tutorial to the letter). I also discovered an audio.hip file on this forum that exhibits the same exact failure that I get from Perter's tutorial leading me to believe that something has changed in audio processing from 12.5 to 13.

 

Basically I want to trigger an existing keyframe animation from the leading edge of a kick drum. I have audio files with the kick drum soloed so I don't need to 'filter' anything. I just need amplitude to somehow trigger an animation at the correct time. I want the kick drum to push an object.

 

Does anyone know how to do this or have a link to a Houdini tutorial that is recently authored to make use of the audio features in Houdini 13?

 

Thanks!

Edited November 25, 2014 by Atom

[edward]

Middle-click on the File CHOP in the Network View pane. What channels is it creating? I tried that audio.hip with the file set to "C:/Windows/Media/ding.wav" and it has 2 channels chan0 and chan1 for me.

[Atom]

Thanks for replying.

 

When I middle click on the Audio File node I see two channels, chan0 and chan1. My loop file was made by the Cakewalk Sonar X2 program. It is 5.71 seconds long and uses 3935Kb.

 

Try a "true", red-book audio,  musical stereo wave file @44.1Khz not just a low-res system file.

 

freesound.org has some files.

Edited November 21, 2014 by Atom

[edward]

So at which stage is the "chan0" channel disappearing for you? I can't see that happening with audio.hip

[Atom]

Here is a screen shot from the audio.hip file mentioned above with the link.

 

In the CHOP net everything is fine. However, when referencing the CHOP Channel, the audio does not exist. (This is exactly as Peter's tutorial). I examine the CHOP Channel node and notice that the Channel Scope is set to audio and the attribute scope is set to audio. But the node complains that chan0 does not exist. (It does exist in the CHOP net)

 

So I try typing chan over type audio in the CHOP Channel. I also try typing chan0 over top the channel and the scope. No combination seems to work. The nodes won't cook.

 

I am attaching the wave I am using as well.

 

To repeat my experience just open the HIP file and browse to the attached wave which plays fine.

en_egs_drums-1a.wav

Edited November 22, 2014 by Atom

[edward]

Sorry, I took a slightly more detailed look at the audio.hip. It looks like that set up should have only ever worked with the switch set up to use the noise because the downstream nodes requires a channel per point of the grid. So I ended up just making the File CHOP side of it do the same thing. See the attached file. I also made sure to resample the audio to 24 FPS because otherwise it was unnecessarily creating too much data that never gets used.

 

Mind you, I'm not sure if the results are quite correct but at least the geometry looks interesting when you hit play now.

audio_fix.hip

[Atom]

Edward, thank you for making the change to the file, it does work. I am gong to review it and see if I leverage portions to make my scene.

[Atom]

I now have a working kick driven animation. The next step is to somehow accumulate the kick information into a variable. I am not sure how to proceed with that step?

 

For example lets say I have 10 beats that happen over a range of frames. I want to use each kick to push an object further down a path. So I need a way to count each beat. Then I need a way to route that count to a Position along a path.

 

Does anyone have any tips on constructing a counting beat network?

[zoki]

Hi Peon

you seem to be deep into chops

here is a book and files , only one out there so far as I know dealing extensivly with chops and audio.

It is very cheap and full of goodies

Highly recommended for all starting with audio in houdini

http://www.andrew-lowell-productions.com/andrew-lowell-productions/resources.html

[Atom]

Thanks for the link, I have visited that site before.

 

But I am pretty close I just need a little help configuring the Record node.

 

If you look at the image you will see the green line is what I currently have working in CHOPS. The red line I drew in photoshop represents what I am trying to achieve. I want a pulse to increase a Constant over time.

ap_accumulate_chop_record.hipnc

Edited November 25, 2014 by Atom

[Atom]

I think I figured it out. There is node called the Count node. By feeding it with the audio wave and a constant value it produces a stepped pattern that rises by the amount of the constant, over time. Setting the Trigger Threshold is important for getting the right values.

Edited November 25, 2014 by Atom

[eetu]

Area CHOP

 

EDIT: Oh ok looks like Count works too

Edited November 25, 2014 by eetu

[eetu]

More specifically, Area CHOP does "proper" accumulation or integration of the signal, but looks like Count fits your case perfectly.