DriveWorks SDK Reference
3.0.4260 Release
For Test and Development only

Camera-based Headlight Controller
SW Release Applicability: This module is available in NVIDIA DRIVE Software releases.

Auto Headlight

About Auto Headlight Controller

Environment ambient light intensity is the guiding parameter to control low beam headlight in mordern vehicle. Headlight should perform turning on in scenes like night, tunnel, garage and etc. This module is aimed to use camera input, to predict the ambient light intensity. Lux has been used as the unit for intensity measurement. The core algorithm of the module serves as a lux estimator.

The lux estimator need to be implemented case by case due to difference between variat cameras. AR0231 camera is the main featured camera type on NVIDIA AGX platform. Auto healight controller module has general API design to work with multiple camera types, but at this moment, only AR0231 camera series is supported, API function call with other type cameras will return 'NOT SUPPORTED'.

Implementation for AR0231 camera is a histogram based mapping algorithm, camera metadata lines appended after bottom pixel lines of each frame already contains a sensor generated histogram. A dedicated parser was constructed for AR0231 camera metalines.

After histogram is parsed and unified, it will be passed to a set of boratory calibrated coefficients and finally mapping to a single lux value. This lux value will be further mapped to a float control signal range from 0 to 1. To avoid flickering and guarantee responsiveness, a fine-tuned low pass filter has been applied during this mapping.

Relevant Tutorials