Performance evaluation of mail-scanning cameras

bstract. Letter-scanning cameras (LSCs) form the frontend imging systems for virtually all mail-scanning systems that are curently used to automatically sort mail products. As with any visionependent technology, the quality of the images generated by the amera is fundamental to the overall performance of the system. We resent novel techniques for objective evaluation of LSCs using omparative imaging—a technique that involves measuring the fielity of target images produced by a camera with reference to an mage of the same target captured at very high quality. Such a ramework provides a unique opportunity to directly quantify the amera’s ability to capture real-world targets, such as handwritten nd printed text. Noncomparative techniques were also used to easure properties such as the camera’s modulation transfer funcion, dynamic range, and signal-to-noise ratio. To simulate realorld imaging conditions, application-specific test samples were deigned using actual mail product materials. © 2010 SPIE and S&T. DOI: 10.1117/1.3421975