move matching TrapCode Particular?

I would appreciate help finding a tutorial that I need to study.

It showed a complex, abstract, flowing form (perhaps from Trapcode Particular) superimposed on a video shot while walking down a sidewalk. The particular effect was move-matched, so that as the camera's POV changed from looking frontwards to sideways to looking back, the particles were integrated into the scene. It was as if the particles were walking down the sidewalk, and the camera overtook them.

Or so I remember - could be wrong.

At any rate it was incredible, and I'd like to learn how it's done. If you've seen that or a similar tutorial, please share!

Thanks.

Bob C

[Joseph Pole] "is this the clip you're thinking of?"

Precisely the one. Now to persuade the creator to discuss how he did it. Have you explored these kinds of techniques? I really like the idea of tracking the real world along with particles. It transforms them from "cool" to "magic."

Thanks very much!

Bob C

It's not a question of motion matching the particles. You just have the AE camera match the footage. This tutorial covers it.

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