Inverse of LinearDepth?

[mrboni]

The LinearDepth tfx maps a depth texture value to linear depth using the projection matrix

How do I do this in reverse? Ie take a linearised depth texture and turn it into a typical depth map.

I ask this because I want to use the kinect depth and colour textures with the ColorAndDepth node to add 3d objects into the (full colour frame of the) kinect image

[antokhio]

Reverse tp.43 and to tp.44 if I remeber function correctly… I think what it does is converts depth from raw format to 0-1 range I maybe wrong…
otherwise you can check some map range function…

[mrboni]

Thanks Antokhio

Got it…

To get linear we do -

float ld=tP._43/(d-tP._33);

so to get nonlinear we do -

float d=(tP._43/ld) + tP._33;