Bahram Javidi

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We propose a new optical encoding method of images for security applications. The encoded image is obtained by random-phase encoding in both the input and the Fourier planes. We analyze the statistical properties of this technique and show that the encoding converts the input signal to stationary white noise and that the reconstruction method is robust.
A nonlinear joint transform image correlator is investigated. The Fourier transform interference intensity is thresholded to provide higher correlation peak intensity and a better defined correlation spot. Analytical expressions for the thresholded joint power spectrum are provided. The effects of nonlinearity at the Fourier plane on the correlation signals(More)
A joint Fourier transform image correlator that uses a binary spatial light modulator at the Fourier plane is presented. In this system, the Fourier transforms interference intensity is thresholded to only two values so that a binary spatial light modulator can be used to read out the interference intensity. The performance of the correlator introduced here(More)
A method for optical encryption of three-dimensional (3D) information by use of digital holography is presented. A phase-shifting interferometer records the phase and amplitude information generated by a 3D object at a plane located in the Fresnel diffraction region with an intensity-recording device. Encryption is performed optically by use of the Fresnel(More)
In this paper, we discuss the compression results of full color 3D Integral Images (II) by MPEG-2 (Motion Picture Experts Group). II is a popular three-dimensional image video recording and display technique. The huge size of II data has become a practical issue for storing and transmitting of 3D scenes. The MPEG is a standard coded representation of moving(More)
We propose a three-dimensional (3D) imaging technique that can sense a 3D scene and computationally reconstruct it as a 3D volumetric image. Sensing of the 3D scene is carried out by obtaining elemental images optically using a pickup microlens array and a detector array. Reconstruction of volume pixels of the scene is accomplished by computationally(More)
Photon-counting imaging is integrated with optical encryption for information authentication. An image is double-random-phase encrypted, and a photon-limited encrypted image is obtained. The photon-counting encrypted image is generated with few photons and appears sparse; however, we show that it has sufficient information for decryption and authentication.(More)
A technique that combines the high speed and the high security of optical encryption with the advantages of electronic transmission, storage, and decryption is introduced. Digital phase-shifting interferometry is used for efficient recording of phase and amplitude information with an intensity recording device. The encryption is performed by use of two(More)