Velocityblender 4 noise reduction technique(update)

Velocityblender 4 noise reduction technique (update)

One of the biggest problems with CG is the noise, it takes a lot of CPU power to render an animation without it, and sometimes is not possible to get rid of it without going to insane long render times.

(update): since I’m working again in animation, I revisited this gizmo and made some changes.

A dinosaurs project that I use vb4 for denoise

The story: In 2014 at the beginning of the King Julien show we had this problem, one solution I used to do when I was a painter is blend frames in the patches so it looks smooth. With Jordan Cho, a great comp and vfx artist we figure out that if the velocity is used to mask the frame blending in a CG character we can reduce the noise of it.

Then the logic was if the character is not moving much the blending will be more effective, as soon begin to move the motion blur will make the noise imperceptible.

(update): I had to go back into the gizmo a few weeks ago, update so it works in Vray and Arnold render output and tweak some settings. I added a median for dark tones and better masking option to take out things that could generate ghosting.

Some productions where was used VelocityBlender to improve noise

Since latest version of Nuke has already something similar and we found out that our tool in the Internet and also being used in some studios.

VelocityBlender:

The node have been thru a lot of changes, depending the show, but this a vanilla version it have customs mask and exclusions for props that don’t need blend or generates ghosting, have triple blending to get rid of complicated character noise. At the end to make the thing easier for the artist, there is tree setups. action, talking, staying still. But also there where custom versions tailored for different shows.

Different setting for the action of the characters:

Talking, walking for general use and movement of the character
Stays almost still, it will clean as much of noise is possible
Action characters, not much noise is reduced, but because the movement is not noticeable.
the range is how much of the character will be denoise when he don’t move
Green:not being denoise; Blue denoise active for that part.

Velocityblender was used in a series of projects like King Julien, Puss and Boots and become one of the main tool in the studio, also in other projects that needed noise cleanup, there was custom made for those specific need.

Download vanilla version here