이산 웨이블릿 패킷 변환을 이용한 디지털 홀로그램의 암호화

Digital Hologram Encryption using Discrete Wavelet Packet Transform

  • 발행 : 2008.11.30

초록

본 논문에서는 이산 웨이블릿 패킷 변환을 이용하여 디지털 홀로그램의 중요 성분을 추적하고 암호화하는 새로운 방법을 제안한다. 공간과 주파수 영역에서 디지털 홀로그램의 특성을 분석하여 디지털 홀로그램을 다루는데 필요한 정보를 얻는다. 얻어진 정보들을 종합하여 웨이블릿 변환과 부대역의 패킷화를 이용한 암호화 방법을 제안한다. 웨이블릿 변환의 레벨과 에너지 값을 선택함으로써 다양한 강도로 암호화가 가능하다. 암호화 효과를 수치 및 시각적으로 분석하여 최적의 파라미터를 제시한다. 따라서 별도의 분석과정 없이 본 논문에서 제시된 파라미터를 이용하여 효율적으로 암호화를 수행할 수 있다. 실험결과를 살펴보면 전체 데이터 중에서 단지 0.032%의 데이터만을 암호화하더라도 객체를 분간할 수 없다. 부대역의 패킷화 정보와 암호화 시 이용한 키를 전체 암호키로 이용할 수 있다.

In this paper, we propose a new method which estimates and encrypts significant component of digital hologram using discrete wavelet packet transform (DWPT). After analyzing the characteristics of digital hologram in spatial and frequency domain, the required information for ciphering digital hologram was extracted. Based on this information an ciphering method was proposed with wavelet transform and packetization of subbands. The proposed algorithm can encrypt digital hologram in various robust from selecting transform-level and energy threshold. From analyzing the encryption effect numerically and visually, the optimized parameter for encryption is presented. Without additional analyzing process, one can encrypt efficiently digital hologram using the proposed parameter. Although only 0.032% among total data is encrypted, the reconstructed object dose not identified. The paketization information of subbands and the cipher key can be used for the entire secret key.

키워드

참고문헌

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