The mathematical transforms such as Fourier transform, wavelet transform and fractional Fourier transform have long been influential mathematical tools in information processing. These transforms process signal from t...
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The mathematical transforms such as Fourier transform, wavelet transform and fractional Fourier transform have long been influential mathematical tools in information processing. These transforms process signal from time to frequency domain or in joint time-frequency domain. In this paper, with the aim to review a concise and self-reliant course, the discrete fractional transforms have been comprehensively and systematically treated from the signalprocessing point of view. Beginning from the definitions of fractional transforms, discrete fractional Fourier transforms, discrete fractional Cosine transforms and discrete fractional Hartley transforms, the paper discusses their applications in image and video compression and encryption. The significant features of discrete fractional transforms benefit from their extra degree of freedom that is provided by fractional orders. Comparison of performance states that discrete fractional Fourier transform is superior in compression, while discrete fractional cosine transform is better in encryption of image and video. Mean square error and peak signal-to-noise ratio with optimum fractional order are considered quality check parameters in image and video.
wavelet analysis is a powerful tool with modern applications as diverse as: imageprocessing, signalprocessing, data compression, data mining, speech recognition, computer graphics, etc. The aim of this paper is to i...
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Alzheimer's disease (AD) is an irreversible and progressive brain disease that gradually destroys memory and thinking skills to an extent that it starts affecting the daily life. It has become the most common caus...
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Alzheimer's disease (AD) is an irreversible and progressive brain disease that gradually destroys memory and thinking skills to an extent that it starts affecting the daily life. It has become the most common cause of dementia among older people. The work presented in this paper evaluates the utility of imageprocessing on the Magnetic Resonance Imaging (MRI) scans to estimate the possibility of an early detection of AD. The total brain atrophy and specifically the hippocampal atrophy are considered strong diagnostic tests for AD. T1 weighted MRIs have been used for the purpose of imageprocessing to evaluate atrophy. The paper demonstrates the applications of several imageprocessing techniques such as K-means clustering, wavelet transform, watershed algorithm and also a customized algorithm tailored for the specific case. It has been implemented on the open source platforms, OpenCV and Qt, which facilitates the implementation and utility of the developed product in the hospitals without requiring any proprietary software. The results obtained from the project could aid the analysis to detect AD along with correlation with the psychiatric results and could thus assist the doctors in detecting AD at an early stage. This could progressively help in understanding and treating AD.
Pan-sharpening is a technique which provides an efficient and economical solution to generate multi-spectral (MS) images with high-spatial resolution by fusing spectral information in MS images and spatial information...
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Pan-sharpening is a technique which provides an efficient and economical solution to generate multi-spectral (MS) images with high-spatial resolution by fusing spectral information in MS images and spatial information in panchromatic (PAN) image. In this study, the authors propose a new pan-sharpening method based on weighted red-black (WRB) wavelets and adaptive principal component analysis (PCA), where the usage of WRB wavelet decomposition is to extract the spatial details in PAN image and the adaptive PCA is used to select the adequate principal component for injecting spatial details. WRB wavelets are data-dependent second generation wavelets. Multi-resolution analysis (MRA) based on WRB wavelet transform shows a better de-correlation of the data compared with common linear translation-invariant MRA, which makes it suitable for applications requiring manipulating image details. A local processing strategy is introduced to reduce the artefact effects and spectral distortions in the pan-sharpened images. The proposed method is evaluated on the datasets acquired by QuickBird, IKONOS and Landsat-7 ETM + satellites and compared with existing methods. Experimental results demonstrate that the authors method can provide promising fused MS images with high-spatial resolution.
This paper proposes a new scheme for secure digital watermarking and copyright protection of videos. The approach presented here is based on redundant discrete wavelet transform (RDWT) and singular value decomposition...
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This paper proposes a new scheme for secure digital watermarking and copyright protection of videos. The approach presented here is based on redundant discrete wavelet transform (RDWT) and singular value decomposition (SVD). The video frames and the watermark are decomposed by RDWT, and the watermark is embedded into the subbands of the I-frames. The singular values of the I-frames are modified with the singular values of the visual watermark. Meanwhile, the watermark embedding strength is adjusted adaptively using the noise visibility function (NVF) with local properties. The approach is efficient and appropriate for real-time applications. The experimental results demonstrate that the proposed approach has good performance in preserving high quality of the video, and the watermark can be extracted accurately after various attacks.
In this paper, a new approach for image edge detection using wavelet based ant colony optimization (ACO) is proposed. The proposed approach applies discrete wavelet transform (DWT) on the image. ACO is applied to the ...
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ISBN:
(纸本)9781479948741
In this paper, a new approach for image edge detection using wavelet based ant colony optimization (ACO) is proposed. The proposed approach applies discrete wavelet transform (DWT) on the image. ACO is applied to the generated four subbands (Approximation, horizontal, vertical, and diagonal) separately for edge detection. After obtaining edges from the 4 subbands, inverse DWT is applied to fuse the results into one image with same size as the original one. The proposed approach outperforms the conventional ACO approach.
Digital watermarking is a process to provide authenticity by hiding a data into an image or audio or document. Hiding of data in an image can be done in frequency domain. Since frequency domain based techniques are mo...
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ISBN:
(纸本)9781479930913
Digital watermarking is a process to provide authenticity by hiding a data into an image or audio or document. Hiding of data in an image can be done in frequency domain. Since frequency domain based techniques are more robust against signalprocessing and geometric attacks than time domain based techniques and watermark can also be extracted with(non blind) and without(blind) original cover image. In this paper we proposed a blind image watermarking technique which embeds watermark into image in frequency domain using discrete wavelet transform, singular value decomposition and torus automorphism techniques. This technique extracts watermark without cover image and also proved that this method is robust against different signal and non signalprocessing attacks.
With the development of sensor technology, an increasingly number of remote-sensing image data with different spatial resolutions and spectral resolutions will be applied in the engineering and remote-sensing image fu...
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The basic objective of this paper is to analyze the concept of wavelet based algorithms for image compression using different parameter. All algorithms are based on still images, The algorithm involved in the comparat...
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ISBN:
(纸本)9781479933587
The basic objective of this paper is to analyze the concept of wavelet based algorithms for image compression using different parameter. All algorithms are based on still images, The algorithm involved in the comparative analysis is wavelet Difference Reduction (WDR), Spatial orientation tree wavelet (STW), Embedded zero tree wavelet (EZW) and modified Set Partitioning in hierarchical trees (SPIHT). These algorithms are more effective and deliver a better feature in the image. In compression, wavelets transform have shown a good elasticity to a large amount of data, while being of realistic complexity. These techniques are used in many imageprocessingapplications. The techniques are compared by using the performance parameters peak signal to noise ratio (PSNR) & mean square error (MSE).
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