Perception

Photometric Calibration

Photometric calibration is the process of estimating a camera's radiometric response function, vignetting profile, and exposure parameters so that recorded pixel intensities can be related to actual scene radiance. It complements geometric calibration and is essential for direct visual odometry and SLAM methods, such as DSO, that minimize photometric error between frames rather than matching sparse features.

Why it matters for physical AI

Direct visual SLAM and neural scene reconstruction both assume intensities are comparable across frames; uncorrected auto-exposure and vignetting silently degrade them, so photometric calibration often decides whether such pipelines work outside the lab.