Annual Report 2012–13

Pushing Knowledge Frontiers 27 Binocular Tone Mapping Technology More and more filmmakers produce movies in 3D nowadays. However, limited by their dynamic range, conventional 3D display devices can only present a much smaller range of intensity with some loss of fine details and textures. Although the fast-growing HDR (High dynamic range) technology can preserve richer content of images, conventional display technology lacks the ability to show the subtle textures and details in high contrast scenes of HDR outputs. To tackle the problem, Prof. Wong Tien-tsin at the Department of Computer Science and Engineering and his team has developed an innovative technology called ‘Binocular Tone Mapping’. A human’s eyes are like two independent visual receptors. When two eyes see two images with a certain degree of differences, the brain can naturally fuse the differences from both views. The CUHK team made use of this property of human vision to develop ‘Binocular Tone Mapping’, which synthesizes a pair of images, one exhibits high contrast, the other preserves rich texture details at both dark and bright areas. With a pair of 3D glasses and a 3D display device, a viewer can simultaneously visualize the image pair. These images are optimally synthesized in a way such that the viewer’s brain can naturally fuse the two views, and perceive more visual content than any single image can offer. The dark and bright regions of the image, including rich colour and texture details, can be shown clearly. 無創性手術治療腦動靜脈畸形 外科學系、影像及介入放射學系和腫瘤學 系的研究人員自 1998 年起共同進行多項臨 床研究，證實無創性直線加速器放射手術 能有效治療腦動靜脈畸形。 腦動靜脈畸形是年輕人中風的元兇，香港 每年約有七八十名年齡介乎十至四十歲病 人患上腦動靜脈畸形出血。放射手術屬於 無創治療，是通過單次高劑量的 X 光準確地 投射在病變部位，令血管內皮細胞增殖，形 成血栓，以減少畸形血管的血流量，最終使 畸形血管成為無害的疤痕。 自 1998 年至今，已有超過一百位病人接受 放射手術成功治療腦動靜脈畸形。研究小 組發現治療腦動靜脈畸形成功率超過百分 之八十六，並把研究結果刊於 2012 年 7 月刊 載於《臨床神經科學雜誌》。 「雙目立體影調融合」新技術 立體電影近年大行其道，但傳統顯示設備 受最大亮度和灰階級別所限，不能全面展 現畫面中最暗至最亮的所有亮度。現時迅 速發展的高動態範圍技術，雖可保留更多 畫面細節，但在一般屏幕（例如電視或手 機屏幕）上觀看，畫面的光暗對比會大打折 扣，令強烈的光暗對比和豐富的紋理細節 無法並存。 左起：腫瘤學系醫學物理學家 魏遠勤先生、外科學系腦外科組教授 黃國柱教授、影像及介入放射學系 名譽臨床助理教授蕭容媛醫生、腫瘤 學系名譽臨床副教授甘冠明醫生 From left: Mr. Ngar Yuen-kan Dennis, medical physicist, Department of Clinical Oncology; Prof. Wong Kwok-chu George, professor, Division of Neurosurgery, Department of Surgery; Dr. Siu Yung- woon Deyond, clinical assistant professor (honorary), Department of Imaging and Interventional Radiology; and Dr. Kam Koon-ming Michael, clinical associate professor (honorary), Department of Clinical Oncology