Effective Dynamic Range Evaluation of Digital Still Images in Mobile Devices

Abstract

Digital photography has immersed in everyday surroundings through mobile devices which became the most popular tool for taking pictures. However, the compactness of these devices is an obstacle for certain image quality parameters when it comes to usability. The purpose of this paper is to analyze the effective dynamic range of mobile device cameras. We obtained opto-electric conversion function (OECF) measurements according to ISO standard for total and effective dynamic range evaluation. Additionally, the evaluation of effective dynamic range using high dynamic range image construction was performed where algorithms for tone mapping were applied. Our findings indicate little difference in OECF values among different mobile device cameras, as well as for the total dynamic range values. However, when it comes to the effective dynamic range, cameras in these devices show less input-output conversion stability. Additionally, tone mapping indicates that the effective dynamic range is different between devices.

Keywords

• digital imaging
• dynamic range
• image processing
• mobile devices
• tone mapping
• objective metrics