Is there a possibility to trim channel at current value (using expression)?
For example to leave only data with values between 1 and 2.

I'm trying to make an animated reference for copy stamping stretch CHOP parameters.

Thanks

Peter

peliosis
Is there a possibility to trim channel at current value (using expression)?
For example to leave only data with values between 1 and 2.

I'm trying to make an animated reference for copy stamping stretch CHOP parameters.

Thanks

Peter

Trimming cuts off stuff at the left and the right of the channel. Yes, you can make the trim as short as a single sample. However, trimming based on a min/max of the input is trickier, and takes multiple steps.

1) make two expression chops from your source; one's default output is the value that is the index of the first frame, the other the last frame.
2) on each one, set the output value to either a) the input value, or b) the current frame. Output b) if it's between one and two, else a).
3) the result is that you can now get the chopmin() from one and the chopmax() from the other. Since you set the output to be the current frame iff the input was inside your desired range, then the max of that channel is the last frame at which your conditions were met.
4) append the trim CHOP using the above chopmin/max functions.

Thank you very much for the instructions, it works great, but
I'm a beginner especially in chops, and I have another question…
I needed the trim to create a reference for stretch chop.

I'm looking for a method to copy custom (prepared keframe) animation using triggered copy, but each of the copies have to be of different length.

The length (stretch) of each copy needs to be controled by trigger length.
I can't find a way to do it.
I tried copy stamping stretch “end” parameter, using the trimmed channel as a stretch reference, but houdini stretched all of the copies instead of one.
I spent some time on it but I still doubt in my chop knowledge.
If you could be of some help again, I'd be very grateful.

Thanks

Peter