Title :
Fast Auto-Focus Control Algorithm Using the VCM Hysteresis Compensation in the Mobile Phone Camera
Author :
Kim, Tae-Kyu ; Sohn, Jae-Sik ; Lee, Suk-Hwan ; Kwon, Ki-Ryong ; Kim, Duk-Gyoo
Author_Institution :
Sch. of Electr. Eng. & Comput. Sci., Kyungpook Nat. Univ., Taegu
Abstract :
A practical real-time auto-focus algorithm for a digital camera is presented in this paper, and it improves the reliability and speed of the auto-focus process, especially suitable for a 2 mega-pixel high definition camera. The proposed algorithm divides auto-focusing process into several modes and finds the focus by the different control current in the each mode. Additionally, an adaptive step size searching and a hysteresis compensation of the voice coil motor increased searching speed. The experimental result shows the proposed algorithm is faster auto-focusing than conventional algorithm in the VCM camera system
Keywords :
cameras; focusing; mobile handsets; search problems; 2 mega-pixel high definition camera; VCM hysteresis compensation; adaptive step size searching; auto-focus control algorithm; mobile phone camera; voice coil motor; Coils; Computer science; Digital cameras; Flowcharts; Focusing; Frequency; Hysteresis motors; Industrial training; Lenses; Mobile handsets;
Conference_Titel :
Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on
Conference_Location :
Toulouse
Print_ISBN :
1-4244-0469-X
DOI :
10.1109/ICASSP.2006.1660872
