Retrieve the exposure regions configured on the camera
#include <camera/camera_3a.h>
camera_error_t camera_get_exposure_regions(camera_handle_t handle, int numasked, int *numsupported, int *numreturned, camera_region_t *regions)
Use this function to retrieve the configured auto exposure regions from the camera. For more information on configuring exposure regions, see camera_set_exposure_regions(). When exposure regions are defined, the auto exposure algorithm gives exposure priority to objects in the defined areas of the scene.
The maximum number of supported exposure regions is determined by checking the numsupported argument when the function completes successfully.
Ensure that the regions argument points to an array which has at least numasked elements allocated. To determine an appropriate size for this array, you can invoke this function in presizing mode by setting the numasked argument to 0 or the regions argument to NULL. When the function is invoked in this presizing mode, the maximum array size required is returned in the numsupported argument. You can then allocate an array of the appropriate size and invoke the function again with the numasked argument set to the value returned previously in the numsupported argument.
The viewfinder must be running before using this function.
CAMERA_EOK when the function successfully completes, otherwise another camera_error_t value that provides the reason that the call failed.