Using wavelet networks, it is possible to capture the characteristics of non-linear dynamic systems in a multi- scale modeling strategy. Starting from the coarsest approximation we go step-wise to the finer scales. At...
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ISBN:
(纸本)0819422134
Using wavelet networks, it is possible to capture the characteristics of non-linear dynamic systems in a multi- scale modeling strategy. Starting from the coarsest approximation we go step-wise to the finer scales. At each step the error signal or the residue of the system is modeled. This procedure is repeated until the residual drops below some modeling error bound. The modeling is carried out using compactly supported biorthogonal wavelets. By choosing appropriate wavelet basis, it is possible to obtain a near optimal model.
We present a coder that yields good quality images at very high compression rates. It performs embedded coding and can carry out both lossy and lossless compression, properties which are suitable for progressive trans...
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ISBN:
(纸本)0819441929
We present a coder that yields good quality images at very high compression rates. It performs embedded coding and can carry out both lossy and lossless compression, properties which are suitable for progressive transmission;It is based on an integer to integer wavelet transform, and uses augmented zerotrees with a hybrid technique that incorporates bitplane coding as well.
The wavelet coefficients in 2-D discrete wavelet transform (DWT) subspaces have a peaky, heavy-tailed marginal distribution that can be well described by a Gaussian mixture statistical model. In this paper, a multisca...
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The wavelet coefficients in 2-D discrete wavelet transform (DWT) subspaces have a peaky, heavy-tailed marginal distribution that can be well described by a Gaussian mixture statistical model. In this paper, a multiscale implementation of fragile watermarks based on the Gaussian mixture model is presented. The presented new method can embed a message bit stream, such as personal signatures or copyright logos, into a host image. With the embedded message bits spreading over the whole image area, the new method can detect and localize any image tampering since it will inevitably destroy a certain message bits. Compared with some other fragile watermark techniques, the statistical model based method modifies only a very small amount of image data to embed watermarks and the modification is hardly perceived by human vision because it occurs at texture edges. Besides, the multiscale implementation of fragile watermarks based on the presented method can help distinguish some normal image operations such as compression from malicious attacks, which is meaningful in terms of semi-fragile watermarking applications.
This paper presents a stationary wavelet transform (SWT) method to de-noise the microarray images. It's well known that SWT is time invariant. Hence it makes particularly important in statistical signalprocessing...
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ISBN:
(纸本)0780376676
This paper presents a stationary wavelet transform (SWT) method to de-noise the microarray images. It's well known that SWT is time invariant. Hence it makes particularly important in statistical signalprocessingapplications, such as signal detection and de-noising. The testing result on sample microarray image has shown a clear and a better resolution image is obtained using this method.
This paper address the problem of modeling of Earth phenomena from remotely sensed images. In the field of remote sensing (RS), the observed phenomena are most often multi-scale phenomena such as the waves in oceans, ...
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ISBN:
(纸本)0819432997
This paper address the problem of modeling of Earth phenomena from remotely sensed images. In the field of remote sensing (RS), the observed phenomena are most often multi-scale phenomena such as the waves in oceans, the spatial organization of street networks in cities. For-extracting information, or processing this kind of images, a multiresolution approach and modeling is often most powerful than classical approaches. We intend to present some winning applications based on multiresolution models derived from the representation provided by multiresolution analysis (MRA) and wavelet transforms (WT). After a short reminder of WT and an example of application to a remotely sensed image, three applications where modeling based on WT improves the quality of results are presented: vine detection, streets extraction in urban areas and improvement of the spatial resolution of remotely sensed images.
In this paper, we illustrate how a recently proposed wavelet-based estimation scheme for 2-D multichannel signals can utilize an overcomplete wavelet expansion or the BayesShrink adaptive wavelet-domain threshold to i...
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ISBN:
(纸本)0819450804
In this paper, we illustrate how a recently proposed wavelet-based estimation scheme for 2-D multichannel signals can utilize an overcomplete wavelet expansion or the BayesShrink adaptive wavelet-domain threshold to improve estimation results. The existing technique approximates the optimal estimator using a DFT and an orthonormal 2-D DWT to efficiently decorrelate the signal in both channel and space, and a wavelet-domain threshold to suppress the noise. Although this technique typically yields signal-to-noise ratio (SNR) gains of over 12 dB, results can be improved 1 to 1.5 dB by replacing the critically-sampled wavelet expansion with an overcomplete wavelet expansion. In addition, provided that the detail subbands of the original signal channels each obey a generalized Gaussian distribution, average channel SNR gains can be improved 3 dB or more using the BayesShrink adaptive wavelet-domain threshold.
This paper proposes an image watermarking algorithm that is robust to compression methods and noise addition. In the proposed method the wavelet transform of images is taken and watermarking is carried out in the wave...
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ISBN:
(纸本)0780383184
This paper proposes an image watermarking algorithm that is robust to compression methods and noise addition. In the proposed method the wavelet transform of images is taken and watermarking is carried out in the wavelet domain. In order to accomplish low visibility of the watermark within the image and enable robustness against attacks, watermarking of block averages is utilized. Experimental results show that the proposed method is considerably more robust against corrupting effects such as JPEG compression, addition of noise, cropping and scaling.
In this paper, we propose an original decomposition scheme based on Meyer's wavelets. In opposition to a classical technique of wavelet packet analysis, the decomposition is an adaptative segmentation of the frequ...
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ISBN:
(纸本)0819432997
In this paper, we propose an original decomposition scheme based on Meyer's wavelets. In opposition to a classical technique of wavelet packet analysis, the decomposition is an adaptative segmentation of the frequential axis which does not use a filters bank. This permits a higher flexibility in the band frequency definition. The decomposition computes all possible partitions from a sequential space: it does not only compute those that come from a dyadic decomposition. Our technique is applied on the electroencephalogram signal (EEG);here the purpose is to extract a best basis of frequential decomposition. This study Is part of a multimodal functional cerebral imagery project.
wavelet transform has been widely used in many signal and imageprocessingapplications such as edge detection and data compression. For applications that tolerate a slight compromise in accuracy for faster speed, a f...
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ISBN:
(纸本)0819425915
wavelet transform has been widely used in many signal and imageprocessingapplications such as edge detection and data compression. For applications that tolerate a slight compromise in accuracy for faster speed, a fast approximation of wavelet transform is favorable. In this paper we propose a simple yet effective algorithm for fast wavelet transform. The use of fixed point numbers simplifies the hardware design and computation complexity than the use of a floating point arithmetic unit. Calculations are further reduced using our thresholding-in-calculations (TIC) technique to omit calculations of small terms that are negligible to the accumulated sum. The TIC technique basically determines whether a multiplication followed by an addition shall be executed using a look-up table with the quantized magnitude of multiplication operands as input parameters. Knowing the levels of quantization, any combination of the quantized multiplication operands can approximate the product and be compared to a predetermined threshold value. If the approximated product is greater than or equal to the threshold value, the corresponding entry in the look-up table is marked for multiplication;otherwise, no multiplication will be executed. Our simulation results show that our approximation algorithm is effective for wavelet transform of audio signals. In addition, when our algorithm is applied to a simple wavelet based edge detection algorithm, the detection result. is almost the same as the one using precise calculation of the wavelet transform.
In this paper, principal component analysis (PCA), laplacian pyramid (LP), discrete wavelet transform (DWT), non-subsampled contourlet transform (NSCT), Bayesian PCA (BPCA), and non-negative matrix factorization (NMF)...
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ISBN:
(纸本)9781538615010
In this paper, principal component analysis (PCA), laplacian pyramid (LP), discrete wavelet transform (DWT), non-subsampled contourlet transform (NSCT), Bayesian PCA (BPCA), and non-negative matrix factorization (NMF) methods are compared in order to obtain a single informative image from visible and thermal images. The quality of the fused images obtained in the experimental studies is evaluated using five different quality metrics.
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