即時視訊錄製系統設計

The Design of Real-Time Video Recording Systems

陳碩宏(Shou-Hung Chen)

指導教授 ： 高文忠

國立臺灣師範大學/科技學院/機電科技研究所/碩士(2005年)

摘要

本研究提出一個整合嵌入式軟體平台的動態影像錄製系統，此系統包含了自動曝光、自動白平衡與數位影像穩定器模組，以及典型的影像壓縮模組。隨著光源的亮度與色溫變化，自動曝光與自動白平衡程序充分利用影像壓縮過程所產生的有用資訊，完成準確而即時的影像估測與調整。所提出的數位影像穩定器演算法由二個部份所組成：一、整體移動估測，由影像畫面找出相機的震動或平移的整體移動向量；二、移動向量補償，依補償向量自原始影像擷取適當的影像區域。整體移動估測與動態影像壓縮分享相同的影像移動估測器，並且使用濾波器移除不穩定的移動向量。
完整的演算法已經在可攜式的數位相機上實現，由實驗結果顯示所輸出的影像畫面呈現較佳的影像穩定情形。

關鍵字

自動曝光 ； 自動白平衡 ； 動態影像壓縮 ； 移動估測 ； 影像穩定 ； 數位影像穩定 ； 整體移動向量 ； 移動補償

並列摘要

This research presents an integrated MPEG video recording system with embedded software platform. The system includes auto exposure, auto white balance, digital image stabilization modules, and other typical video compression modules. By fully utilizing the information obtained from video compression, the real-time auto exposure and auto white balance process can be accurately predicted the brightness as well as color temperature of the light source. The proposed digital image stabilization algorithm is composed of two phases: (1) estimating global motion vector which represents the camera vibration or panning in the scene and (2) compensating motion vector by relocating the cropped image raw data area. The global motion estimation shares the same motion estimator of MPEG encoder and adds a filter to remove the effects of unstable motion vector.

並列關鍵字

Auto exposure ； Auto white balance ； MPEG ； Motion estimation ； Image stabilization ； Digital image stabilization ； Global motion vector ； Motion compensation

參考文獻

[1]Wen-Chung Kao, Chih-Chung Kao, Ching-Kai Lin, Tai-Hua Sun, Sheng-Yuan Lin, "Reusable embedded software platform for versatile camera systems," IEEE Trans. Consumer Electronics, pp. 1379-1386, Vol. 51, No. 4, Nov. 2005.

[2]A. Aysun Yeni, Sarp Erturk, "Fast digital image stabilization using one bit transform based sub-image motion estimation," IEEE Trans. Consumer Electronics, pp. 917-921, Vol. 51, No. 3, Aug. 2005.

[4]Tetsuya Kuno, Hiroaki Sugiura, Narihiro Matoba, "A new automatic exposure system for digital still cameras," IEEE Trans. Consumer Electronics, pp. 192-199, Vol. 44, No. 1, Feb. 1998.

[5]June-Sok Lee, You-Young Jung, Byung-Soo Kim, Sung-Jea Ko, "An advanced video camera system with robust AF, AE, and AWB control," IEEE Trans. Consumer Electronics, pp. 694-699, Vol. 47, No. 3, Aug. 2001.

[6]Rongzheng Zhou, Xuefeng Chen, Feng Liu, Jie He, Tiankang Liao, Yanfeng Su, Jinghua Ye, Yajie Qin, Xiaofeng Yi, Zhiliang Hong, "System-on-Chip for mega-pixel digital camera processor with auto control functions," Proc. 5th Int’l Conf. ASIC, pp. 894-897, Vol. 2, Oct. 2003.