What are CHOPs?

(aka 'CHannel OPerators')

In this Houdini lesson, delve into CHOPs (Channel Operators), a method for creating number and vector sequences separate from geometry. Despite their reputation for complexity, we'll demystify CHOPs, teaching you to craft data channels with Python, VEX, or CHOPs.
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CHOPs, A Comprehensive Introduction

Houdini by SideFX


Key Concepts for CHOPs

  • Channel

    A "channel" is what Houdini calls a time series. It can be a series of numbers or vectors. When creating a channel, take care to specify the sample rate.

  • Sample

    A "sample" is a specific value in a channel (time series). If the channel is a sequence of numbers, then a sample is the number for a specific time. If the channel is a sequence of vectors, the sample is the vector for a specific time.

  • Export

    To attach channel data to a parameter, you "export" the channel. This can be done using the Export CHOP.