Is there a way to do this?

Ouch don't think so, if the CHOP was fetched from a key-frame channel than you'd paste the original channel / keyframes but here's the problem.

Channels are vector's with keyframes / interpolation.

CHOPs are rasters built of samples.

Just like you can't easily create a vector image from a raster image, you really can't convert a CHOP to keyframes unless there was a very intelligent script of some sort to do it.

You can just write a script that sets a key for every frame on your channel. To evaluate the chop channel, use chopf().

in some cases, you may be able to get away with RMB on the CHOP node and selecting “Edit Data Channels…” which will allow you to adjust the curve much like the keyframes. This locks the CHOP, so unocking it will loose the tweaks.

There is an hscript function ‘chrefit’ that does the same thing. So if you write a script that keyframes the parameter at every frame accodring to the chop value at that frame and then run ‘chrefit’ on that parameter, it will get you the keyframes.

There may be also some better ways…

Rafal

chrefit is really funny. Love it. I wonder if its maximum accuracy makes it save solution for cleaning mocap/tracking data..?

i'm no expert on cleaning mocap data, but i would guess that chrefit could be used. It just fits piecewise cubic Bezier curves, which approximate the original curve up to maximum discrepancy distance squared of the given limit (passed by -t to the chrefit). So, you may just need to try a few tolerance values and see if the smoothed curve does not loose any important animation gestures.

Rafal

For mocap data, what type of problems usually exist? There's all kinds of options in the Filter and Pass Filter CHOPs.

I meant to make it lighter since it's helpful in case of mixing dozens of motion clips in crowd sim.

Make sure the “unload” toggle is turned on for the nodes for lots of samples / channels.

Also, it can be resampled to a lower rate but that probably won't be good. I haven't had problems with anything even close to 24fps yet but I guess it would depend on how many motions / characters / etc you're using, and how long the shot is etc.

Is there a specific issue?

Thanks guys. I was trying to get channels from Max into Houdini. I used the asset on exchange and it kind of worked. Something went wrong with the chrefit thing, but I that's probably something that can be solved since with a simple wave CHOP everything worked as expected.
I have the feeling that chrefit doesn't work if there is only 1 sample at frame 1 or something. I'll look into that further.

Thanks for the directions.

D.

I think chrefit fits everything between the first and last key of the channel.

If a channel is overidden from CHOP's shouldn't the CHOP netowrk the channel is referencing contain the curve and the keyframes. Then all you have to do is ‘edit data channels’..? Or am I missing something here?

There is also the spline CHOP, but it's kinda ropey..