Don't worry, I didn't know what "pre-viz" was before watching this either...
Basically it's a "3-D storyboard" displaying the "architecture of the visual effects shots," says the expert in the video -- now go find out more.
Previz supervisor Sean Mathiesen and director Danny Boyle, explain the "the architecture" of the visual effects shot.
Don't worry, I didn't know what "pre-viz" was before watching this either...
Basically it's a "3-D storyboard" displaying the "architecture of the visual effects shots," says the expert in the video -- now go find out more.
very concise and excellent description