Wavelet Base Secure Spread Spectrum Image Watermarking
碩士 === 國立中興大學 === 電機工程學系 === 91 === The digital watermarks should be hided and invisible by the human visual system. The spread spectrum techniques are used to achieve the goal. The original image is transformed form spatial domain to frequency domain by using discrete wavelet transform (...
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ndltd-TW-091NCHU04420332015-10-13T17:02:18Z http://ndltd.ncl.edu.tw/handle/45502910987963543672 Wavelet Base Secure Spread Spectrum Image Watermarking 基於小波轉換之安全性展頻數位浮水印 Hsiao-Cheng Hsu 許孝成 碩士 國立中興大學 電機工程學系 91 The digital watermarks should be hided and invisible by the human visual system. The spread spectrum techniques are used to achieve the goal. The original image is transformed form spatial domain to frequency domain by using discrete wavelet transform (DWT). We insert the spread spectrum PN-code and use modulo-2 operator to secure the watermark. The watermark is embedded into the LL3 sub-band after 3 times DWT. A multilevel detection is proposed to effectively watermark which can increase the retrieval performance. Form the experimental result, the proposed method is robust even under heavy attacks. For example, big compression ratio for JPEG and JPEG 2000, the retrieval watermarks still survive. Y. C. Ouyang 歐陽彥杰 2003 學位論文 ; thesis 0 zh-TW |
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碩士 === 國立中興大學 === 電機工程學系 === 91 === The digital watermarks should be hided and invisible by the human visual system. The spread spectrum techniques are used to achieve the goal. The original image is transformed form spatial domain to frequency domain by using discrete wavelet transform (DWT). We insert the spread spectrum PN-code and use modulo-2 operator to secure the watermark. The watermark is embedded into the LL3 sub-band after 3 times DWT. A multilevel detection is proposed to effectively watermark which can increase the retrieval performance. Form the experimental result, the proposed method is robust even under heavy attacks. For example, big compression ratio for JPEG and JPEG 2000, the retrieval watermarks still survive.
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Y. C. Ouyang |
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Y. C. Ouyang Hsiao-Cheng Hsu 許孝成 |
author |
Hsiao-Cheng Hsu 許孝成 |
spellingShingle |
Hsiao-Cheng Hsu 許孝成 Wavelet Base Secure Spread Spectrum Image Watermarking |
author_sort |
Hsiao-Cheng Hsu |
title |
Wavelet Base Secure Spread Spectrum Image Watermarking |
title_short |
Wavelet Base Secure Spread Spectrum Image Watermarking |
title_full |
Wavelet Base Secure Spread Spectrum Image Watermarking |
title_fullStr |
Wavelet Base Secure Spread Spectrum Image Watermarking |
title_full_unstemmed |
Wavelet Base Secure Spread Spectrum Image Watermarking |
title_sort |
wavelet base secure spread spectrum image watermarking |
publishDate |
2003 |
url |
http://ndltd.ncl.edu.tw/handle/45502910987963543672 |
work_keys_str_mv |
AT hsiaochenghsu waveletbasesecurespreadspectrumimagewatermarking AT xǔxiàochéng waveletbasesecurespreadspectrumimagewatermarking AT hsiaochenghsu jīyúxiǎobōzhuǎnhuànzhīānquánxìngzhǎnpínshùwèifúshuǐyìn AT xǔxiàochéng jīyúxiǎobōzhuǎnhuànzhīānquánxìngzhǎnpínshùwèifúshuǐyìn |
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1717779575044308992 |