Warp CHOP

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Summary

The Warp CHOP time-warps the channels of the first input (the Pre-Warp Channels) using one warping channel in the second input (the Warp Curve). The Warp Curve acts as either a rate control or an index control, as explained below. The Warp CHOP usually works on non-time-sliced channels, like pre-key-framed channels of motion. See also the Lookup CHOP, the Speed CHOP and the Oscillator CHOP.

In the Rate Control Method, feeding the Warp CHOP a Warp Curve with a constant value of 1 makes the output identical to the Pre-Warp Channels, assuming the two inputs have the same start-end interval. That is, where the rate is 1, the Pre-Warp Channels are not warped.

Where the Warp Curve is above 1, it causes a speed-up in the animation. Where the Warp Curve is below 1, it causes a slow-down in the animation. Rates less than 0 cause the animation to go in reverse.

In the Index Control Method, the Warp Curve acts as an index into the first input. If the Warp Curve is a straight ramp with a slope of 1 (in Units), it produces unwarped output channels. If Units is set to Seconds, a Warp Curve value of 0 gets the Pre-Warp Channels' values at time 0 seconds. A Warp Curve value of 2 gets the Pre-Warp Channels' values at time 2 seconds.

The Warp CHOP will output the same number of channels and channel names as the Pre-Warp Channels input, and the sample rate will be the same as that of the Pre-Warp input. However, the CHOP will output the same start-end time interval as the Warp Curve input.

If you take a Warp Curve and pass it directly to a Warp CHOP with the Rate Control Method, it is equivalent to passing the same curve to an Speed CHOP and then passing it to the Warp CHOP with the Index Control Method.

PythonIcon.png warpCHOP_Class

Parameters

Method - The warping method to use: Rate or Index Control.

Stretch Indices To Channel Length - If on, the minimum and maximum values in the Warp Curve are mapped to the beginning and end of the channels to be warped. Otherwise, the Warp Curve is applied as-is to the Pre-Warp Channels.

The Warp CHOP does linear interpolation of the Pre-Warped Channels when they are both stretched and compressed.

Standard Options and Local Variables