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Low-power Focus Value Calculation Algorithm using modified DCT for the mobile phone  

Lee Sang-Yong (Department of Electronics Engineering, Korea University)
Park Sang-Soo (Department of Electronics Engineering, Korea University)
Kim Soo-Won (Department of Electronics Engineering, Korea University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea SD / v.42, no.11, 2005 , pp. 49-54 More about this Journal
Abstract
This paper proposes the low power MDCT algorithm for precise FV with minimum size of sub-window in mobile phone. Proposed algerian uses the coefficient at the middle of whole result process requiring the least number of calculations, since it has a good characteristic when used as standard of the FV and needs minimum amount of operation. In addition, using the DCT result related to the middle frequency makes the characteristic of FV more superior because it suppresses the impulsive noise and difference of focus values is larger than any others. The proposed algorithm is implemented using Verilog HDL and verified using Excalibur-ARM board.
Keywords
Auto-focus; Focus-value; DCT; CIS; Edge detection;
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