Analog Non-Linear Transformation-Based Tone Mapping for Image Enhancement in C-arm CT
Author(s): Shi L, Maier J, Söll C, Röber J, Berger M, Bier B, Fahrig R, Eskofier B, Maier A
Publication year: 2016
Event: IEEE Medical Imaging Conference (MIC)
Event location: Strasbourg, France
Flat-Panel C-arm Computed Tomography (CT) suffers from pixel saturation due to the detector’s limited dynamic range. We describe a novel approach to analog, non-linear tone mapping (TM) for preventing detector saturation. An analog TM operator (TMO) applies a non-linear transformation in a CMOS sensor and its inverse TMO based on 14-bit digital raw data. This is done in order to prevent overexposure and to enhance image quality to 32 bits. The method was applied to the cases of low-contrast head imaging and to that of imaging both knees. Cone-beam projection data with and without overexposure was simulated for a 200° short-scan of the knees and a 360° full-scan of a Forbild head phantom. The results show an increased correlation coefficient of 0.99 compared to 0.96 for overexposed knee data and a higher low-contrast visibility (CC=0.99) compared to linear quantization (CC=0.97).
FAU Authors / FAU Editors How to cite
APA: Shi, L., Maier, J., Söll, C., Röber, J., Berger, M., Bier, B.,... Maier, A. (2016). Analog Non-Linear Transformation-Based Tone Mapping for Image Enhancement in C-arm CT.
MLA: Shi, Lan, et al. "Analog Non-Linear Transformation-Based Tone Mapping for Image Enhancement in C-arm CT." Proceedings of the IEEE Medical Imaging Conference (MIC), Strasbourg, France 2016.