Image-based auto-iris

A system for automatically adjusting an iris opening, comprising:

• a memory configured to receive an image from an imaging system having an iris opening;
• a processor configured to:
• determine a current brightness value for the image at a current f-stop setting;
• classify the image according to one of at least two brightness regimes;
• select a pre-set optimal brightness value based on the classified brightness regime;
• calculate a next f-stop setting based on the current f-stop setting, the current brightness value, and the optimal brightness value;
• repeat steps from receiving the image at a memory through adjusting the iris until an algorithm stopping condition is met, wherein the algorithm stopping condition includes a local convergence check;
• and
• an iris adjustment device configured to adjust the iris opening of the imaging system until the algorithm stopping condition is met.

A method for automatically adjusting an iris opening of an imaging system, comprising:

• providing an imaging system having an iris opening;
• receiving, at a memory, an image from the imaging system;
• calculating, by a processor, an average value of pixels in the image, thus determining a brightness for the image at a current f-stop setting;
• based on the calculated average value, classifying, by the processor, the image according to one of at least two brightness regime classifications, including the steps of classifying the image as bright if the average pixel value is above a brightness threshold, and classifying the image as dark if the average pixel value is below the brightness threshold;
• based on the classifying step, selecting, by the processor, a pre-set optimal brightness parameter;
• calculating a next f-stop setting based on the current f-stop setting, the current brightness value and the optimal brightness value;
• automatically adjusting, by an iris adjustment device, the imaging system's iris opening based on the calculated average value of pixels;
• and
• repeating steps from receiving the image at a memory through adjusting the iris until an algorithm stopping condition is met, wherein the algorithm stopping condition is a local convergence check.