# Velocity Blur Cop?

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Does befit Velocity Blur COP for the work with velocity plane? Maybe someone have a successful example? And nobody knows a good links to the algorithms of velocity blur?

P.S. I can't get good result with Velocity Blur COP and velocity planes

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Does befit Velocity Blur COP for the work with velocity plane? Maybe someone have a successful example? And nobody knows a good links to the algorithms of velocity blur?

P.S. I can't get good result with Velocity Blur COP and velocity planes

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Yes it seems to be broken in the last version.

In the past, Houdini 7, velocity COP works fine with using the velocity plane.

But in this version it seems to be broken when you want to make a per-pixel velocity blur.

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Unfortunately, Velocity blur has never really given what you want. It should likely be renamed or removed. What it does is lookup the velocity at a point and sample the input along that vector. What a real motion blur does is lookup a velocity at a point, and smear that points color over several pixels in the output. This isn't possible to do in VEX without serious performance problems.

If you're using 3D velocity vectors, additionally, you need to convert them to 2D velocity vectors using a depth map or point plane (after all, something moving 50mph a foot away from the camera blurs a lot more than something 100ft away).

Hopefully I can get the time to create a Motion Blur COP at some point, to address this.

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Unfortunately, Velocity blur has never really given what you want. It should likely be renamed or removed. What it does is lookup the velocity at a point and sample the input along that vector. What a real motion blur does is lookup a velocity at a point, and smear that points color over several pixels in the output. This isn't possible to do in VEX without serious performance problems.

If you're using 3D velocity vectors, additionally, you need to convert them to 2D velocity vectors using a depth map or point plane (after all, something moving 50mph a foot away from the camera blurs a lot more than something 100ft away).

Hopefully I can get the time to create a Motion Blur COP at some point, to address this.

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Thanks for info, malexander!

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