Misc - 野村　孝徳

High-Speed Optical Encryption Using Binary Encoding Algorithms

1999 IEEE LEOS Annual Meeting Conference Proceedings     192 - 193   1999年

Phase-encoded joint transform correlator to reduce the influence of extraneous signals

T Nomura

APPLIED OPTICS ( OPTICAL SOC AMER )  37 ( 17 ) 3651 - 3655   1998年06月

　概要を見る

A technique to reduce the influence of the dc and the complex-conjugate correlation signals that are inherent in a joint transform correlator is proposed. The key part of this technique is the use of a phase mask. The mask contributes only extraneous signals, so the influence of the signals is reduced. The desirable correlation signal is not affected, and its shape is retained. Computer simulations confirm the performance of the proposed phase-encoded joint transform correlator. (C) 1998 Optical Society of America.

Application of Phase-Encoded Joint Transform Correlator to Optical Encryption Decoder

Proc. Soc. Photo-Opt. Instrum. Eng.   3490   191 - 194   1998年

Encryption Using Joint-Transform Correlator Architecture for Robust Alignment

Optical Processing & Computing (SPIE Int. Technical Group Newsletter)   9   4   1998年

Phase-Encoded Joint Transform Correlator to Reduce the Influence of Extraneous Signals

Appl. Opt.   37   3651 - 3655   1998年

Phase-encoded joint transform correlator as an optical encryption decoder

T Nomura

ALGORITHMS, DEVICES, AND SYSTEMS FOR OPTICAL INFORMATION PROCESSING ( SPIE-INT SOC OPTICAL ENGINEERING )  3466   246 - 252   1998年

　概要を見る

The phase-encoded joint transform correlator as a decoder of an optical double random phase encoding system is described. By using the phase-encoded joint transform correlator, it is possible to decode the encrypted image with the same random phase mask which was used in the encryption procedure. The decoding algorithm and optical systems are described. Computer simulations confirm the proposed decoding algorithm.

DOI

Phase-encoded joint transform correlator as an optical encryption decoder

Takanori Nomura

Proceedings of SPIE - The International Society for Optical Engineering ( SPIE )  3466   246 - 252   1998年

　概要を見る

The phase-encoded joint transform correlator as a decoder of an optical double random phase encoding system is described. By using the phase-encoded joint transform correlator, it is possible to decode the encrypted image with the same random phase mask which was used in the encryption procedure. The decoding algorithm and optical systems are described. Computer simulations confirm the proposed decoding algorithm.

DOI

Application of phase-encoded joint transform correlator to optical encryption decoder

T Nomura

OPTICS IN COMPUTING 98 ( SPIE-INT SOC OPTICAL ENGINEERING )  3490   191 - 194   1998年

　概要を見る

The application of a phase-encoded joint transform correlator to decryption of an optical image encryption system by a double-random phase encoding is described.

Encryption Using Joint-Transform Correlator Architecture for Robust Alignment

Optical Processing & Computing (SPIE Int. Technical Group Newsletter)   9   4   1998年

Layered blind deconvolution using subband filter banks

T Nomura, M Tamaru

OPTICAL REVIEW ( OPTICAL SOC JAPAN )  4 ( 1B ) 164 - 166   1997年01月

　概要を見る

A blind deconvolution method using the concept of subband filter banks has been proposed. This method makes possible the speedy convergence of solution, due to estimation of supports of the reconstructed images by a deconvolution in the lower layer. We apply the method to blind deconvolution by a simulated annealing algorithm and confirm its usefulness.

DOI

サブバンド・フィルタ・バンクを用いた階層型ブラインド・デコンボリューション(共著)

  4 ( 1B ) 164   1997年

Layered Blind Deconvolution Using Subband Filter Banks

Technical Digest of 1996 International Topcial Meeting on Optical Computing     196   1996年

Layered Blind Deconvolution Using Subband Filter Banks

NOMURA T.

Technical Digest of 1996 International Topcial Meeting on Optical Computing   1   196 - 197   1996年

階層型ブラインド・デコンボリューション

    196   1996年

Diffraction grating using a colloidal liquid of magnetic particles and its characteristics

T Nomura, M Fujigaki, Y Morimoto

17TH CONGRESS OF THE INTERNATIONAL COMMISSION FOR OPTICS: OPTICS FOR SCIENCE AND NEW TECHNOLOGY, PTS 1 AND 2 ( SPIE - INT SOC OPTICAL ENGINEERING )  2778   487 - 488   1996年

磁性流体を用いた回折格子とその特徴

  2778   487   1996年

HAAR WAVELET TRANSFORM WITH INTERBAND PREDICTION AND ITS APPLICATION TO IMAGE-CODING

N KUROKI, M NUMA, T NOMURA, M KAMEDA, K HIRANO

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE ( SCRIPTA TECHNICA PUBL )  78 ( 4 ) 103 - 114   1995年04月

　概要を見る

Although the discrete cosine transform (DCT) and wavelet transform have been used as effective techniques for reducing the redundancy of image waveforms, they have the problems of high complexity and causing block distortion. Tn this paper, a Haar wavelet transform with interband prediction is proposed that permits high-speed processing and which is suitable for coding as a subband decomposition technique since it generates little block distortion in the decoded images. The interband prediction method of this proposed transform method uses the derivative of the low-band waveform to predict the high-band waveform each time a band is split into two subbands. This results in a transform process that gives a prediction residual signal with lower entropy. During the inverse transform, the prediction coefficients obtained from the forward transform are used to predict the high-frequency waveforms and then, by adding the prediction residual, the original high frequency waveforms are reconstructed. Because the high-frequency waveforms are generated that smoothly interpolate the up-sampled, low-frequency waveforms, any block effects from this prediction technique are difficult to see in the decoded image. A detailed analysis of the proposed interband prediction process is performed by interpreting the proposed transform as a subband decomposition process that is based on the use of a symmetric short-kernel filter (SSKF) filter bank; then experiments are conducted that demonstrate its performance as a subband decomposition for coding of real image data and the possibility of progressive build-up of the decoded images. Results show that this transform method is effective for coding image data.

INCOHERENT-ONLY JOINT-TRANSFORM CORRELATOR

T NOMURA, Y YOSHIMURA, K ITOH, Y ICHIOKA

APPLIED OPTICS ( OPTICAL SOC AMER )  34 ( 8 ) 1420 - 1425   1995年03月

　概要を見る

An incoherent-only optical and electronic digital joint-transform correlator is proposed. A technique for the removal of extraneous signals inherent in the incoherent-only joint-transform correlator is also presented. A computer simulation and experimental results confirm the performance of the proposed incoherent-only joint-transform correlator.

Calculation of correlation and convolution using filter banks

Proceedings of the 26th Joint Conference on Imaging Technology     179   1995年

フィルタ・バンクを用いた相関・合成積関数の算出法(共著)

第26回画像工学コンファレンス論文集     179   1995年