A Study of Tone Reproduction for High Dynamic Range Images with Applications to Natural Images and Mammograms

  • 陳 姿秀

Student thesis: Doctoral Thesis


This thesis proposes two tone reproduction approaches one for the displaying of natural high dynamic range (HDR) images and another for improving the detection rate of lesions in HDR mammograms The first proposed tone reproduction technique is based on retinex theory to render HDR images with 8 bit-depth A local tone operator is constructed to adjust the local contrast of images according to the proposed corrected center-surround retinex theory for human visual system The center-surround retinex theory is corrected by combining global and local information to build an illumination map with a proposed 3-zone histogram scheme that clarifies apparent reflectance The merit of the proposed algorithm lies in the balanced presentation of both contrast and details in an image produced by a single scale center-surround retinex operator Experimental results show that the proposed algorithm is robust for processing various HDR images and the resulting images are visually pleasing Moreover optical density image another tone reproduction approach is proposed to help computer-aided detection (CADe) systems improve the detection rate of breast cancer lesions in HDR mammograms This thesis proposed two mammographic CADe systems with transforming a region of interest (ROI) into an optical density image for mass and micro-calcifications (MC) detection Experiments show that the proposed systems both achieve high sensitivity with high specificity and delivers satisfactory performance Furthermore the experimental results also prove that the optical density image helps to improve the detection performance
Date of Award2016 Feb 1
Original languageEnglish
SupervisorShen-Chuan Tai (Supervisor)

Cite this