Performance evaluation of mail-scanning cameras

Letter scanning cameras (LSCs) form the front end imaging systems for virtually all mail scanning systems that are currently used to automatically sort mail products. As with any visiondependent technology, the quality of the images generated by the camera is fundamental to the overall performance of the system. In this paper, we present novel techniques for objective evaluation of LSCs using comparative imaging – a technique which involves measuring the fidelity of target images produced by a camera with reference to an image of the same target captured at very high quality. Such a framework provides a unique opportunity to directly quantify the camera’s ability to capture real-world targets such as handwritten and printed text. Non-comparative techniques were also used to measure properties such as the camera’s modulation transfer function, dynamic range, and signal-to-noise ratio. To simulate real-world imaging conditions, application-specific test samples were designed using...

• Type: Journal
• Year: 2010
• Where: JEI
• Authors: Umesh Rajashekar, Tony Tuan Vu, John E. Hooning, Alan Conrad Bovik
• Keywords: Camera, JEI 2010, Mail Product, Mail Scanning Systems