Flexible Wide Dynamic Range (WDR) processing support in image signal processor (ISP)

Abstract

Wide Dynamic Range (WDR) enables capturing images with extreme light variations within them. Typically, image sensor manufactures enable WDR using their proprietary techniques consisting of actual physical capture method as well as transmission format. This poses extreme challenge for interfacing Image Signal Processor (ISP) as complexity grows significantly to support customized processing & data flow for each WDR techniques. This paper summarizes various WDR techniques from multiple sensor manufactures from ISP standpoint and proposes a flexible architecture to support WDR data flows & processing using software and hardware. The given solution can be mapped to silicon area savings by a factor of N (number of WDR techniques to be supported) & 33% for rest of ISP with additional external memory bandwidth enabling universal WDR receiver.