Camera Exposure Control via Region of Interest Detection

The patent applies local quality by creating a mask that selectively weights different regions of the image. The mask assigns higher weights to regions containing objects of interest (detected via face detection, motion detection, or audio-visual correlation) and lower weights to background regions. This allows the exposure adjustment to be locally optimized for important subjects while being less influenced by high-contrast background elements, thereby maintaining both subject exposure quality and overall image consistency.

The patent implements feedback by continuously monitoring the image content through multiple detection mechanisms (face detection, motion detection, audio-visual correlation) and dynamically adjusting the mask and exposure settings based on detected objects of interest. The system calculates a weighted average luminance using the mask, compares it to target exposure levels, and iteratively adjusts exposure parameters to maintain optimal subject exposure while adapting to varying scene conditions, thus resolving the contradiction between dynamic range coverage and subject exposure quality.

The patent applies preliminary action by performing object detection (face detection, motion detection, audio-visual correlation) and mask generation before the exposure calculation and adjustment process. This pre-processing step identifies regions of interest in advance, allowing the subsequent exposure control to focus computational resources on relevant areas. The mask is prepared beforehand and applied during exposure calculation, enabling faster processing compared to analyzing the entire image without pre-identification of important regions.