A camera capable of quickly updating a region of interest (ROI) in its sensor array is provided. The camera is configured to image individual scan lines of a scan imager created as a scan beam is scanned across a subject. A different ROI is defined for each scan line to be imaged. To achieve this, a table of ROI-defining entries is loaded into the camera prior to imaging the scan lines. The ROI-defining entries are used to update the sensor's ROI during the camera's Frame-Overhead-Time. In this manner, the ROI is changed in between the imaging of consecutive scans lines.
