Share Email Print
cover

Proceedings Paper

A digital ISO expansion technique for digital cameras
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Market's demands of digital cameras for higher sensitivity capability under low-light conditions are remarkably increasing nowadays. The digital camera market is now a tough race for providing higher ISO capability. In this paper, we explore an approach for increasing maximum ISO capability of digital cameras without changing any structure of an image sensor or CFA. Our method is directly applied to the raw Bayer pattern CFA image to avoid non-linearity characteristics and noise amplification which are usually deteriorated after ISP (Image Signal Processor) of digital cameras. The proposed method fuses multiple short exposed images which are noisy, but less blurred. Our approach is designed to avoid the ghost artifact caused by hand-shaking and object motion. In order to achieve a desired ISO image quality, both low frequency chromatic noise and fine-grain noise that usually appear in high ISO images are removed and then we modify the different layers which are created by a two-scale non-linear decomposition of an image. Once our approach is performed on an input Bayer pattern CFA image, the resultant Bayer image is further processed by ISP to obtain a fully processed RGB image. The performance of our proposed approach is evaluated by comparing SNR (Signal to Noise Ratio), MTF50 (Modulation Transfer Function), color error ∝E*ab and visual quality with reference images whose exposure times are properly extended into a variety of target sensitivity.

Paper Details

Date Published: 19 January 2010
PDF: 12 pages
Proc. SPIE 7537, Digital Photography VI, 75370U (19 January 2010); doi: 10.1117/12.838774
Show Author Affiliations
Youngjin Yoo, Samsung Advanced Institute of Technology (Korea, Republic of)
Kangeui Lee, Samsung Advanced Institute of Technology (Korea, Republic of)
Wonhee Choe, Samsung Advanced Institute of Technology (Korea, Republic of)
SungChan Park, Samsung Advanced Institute of Technology (Korea, Republic of)
Seong-Deok Lee, Samsung Advanced Institute of Technology (Korea, Republic of)
Chang-Yong Kim, Samsung Advanced Institute of Technology (Korea, Republic of)


Published in SPIE Proceedings Vol. 7537:
Digital Photography VI
Francisco Imai; Nitin Sampat; Feng Xiao, Editor(s)

© SPIE. Terms of Use
Back to Top