In this paper, we propose a new wideband bearing estimation method based on wavelet transform. By analyzing the relationship between the wavelet transform of the frequency invariant beam's output and the array'...
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ISBN:
(纸本)9781479902699;9781479902675
In this paper, we propose a new wideband bearing estimation method based on wavelet transform. By analyzing the relationship between the wavelet transform of the frequency invariant beam's output and the array's beampattern, we derived spatial power spectrum based on wavelet transform (SPS-WT). The method has good performance on noise suppression by utilizing the statistical uncorrelation character between signals and noise, and also has high resolution on bearing estimation. The performance of the proposed method is illustrated in simulation results.
25 years after the seminal work of Jean Morlet, the wavelet transform, multiresolution analysis, and other space frequency or space scale approaches are considered standard tools by researchers in imageprocessing, an...
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ISBN:
(纸本)9780819464514
25 years after the seminal work of Jean Morlet, the wavelet transform, multiresolution analysis, and other space frequency or space scale approaches are considered standard tools by researchers in imageprocessing, and many applications have been proposed that point out the interest of these techniques. This paper proposes a review of the recent published works dealing with industrial applications of wavelet and, more generally speaking, multiresolution analysis. More than 180 recent papers are presented.
Nonlinearities are often encountered in the analysis and processing of real-world signals. This paper develops new signal decompositions for nonlinear analysis and processing. The theory of tensor norms is employed to...
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ISBN:
(纸本)0819422134
Nonlinearities are often encountered in the analysis and processing of real-world signals. This paper develops new signal decompositions for nonlinear analysis and processing. The theory of tensor norms is employed to show that wavelets provide an optimal basis for the nonlinear signal decompositions. The nonlinear signal decompositions are also applied to signalprocessing problems.
It is of great importance in image restoration to remove noise while preserving and enhancing edges. This paper presents a spatial correlation thresholding scheme for image restoration. The dyadic wavelet transform th...
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ISBN:
(纸本)0819442666
It is of great importance in image restoration to remove noise while preserving and enhancing edges. This paper presents a spatial correlation thresholding scheme for image restoration. The dyadic wavelet transform that acts as a Canny edge detector is employed here to characterize the significant structures, which would be strongly correlated along the wavelet scales. A correlation function is defined as the multiplication of two adjacent wavelet subbands with a translation to maximize the mathematical expectation. In the correlation function, edge structures are more discriminable because they are amplified while noise being diluted. Unlike most of the traditional schemes that threshold directly the wavelet coefficients, the proposed scheme applies thresholding on the correlation function to better preserve edges while suppressing noise. A robust threshold is presented and the experiment shows that the proposed scheme outperforms the traditional thresholding schemes not only in SNR comparison but also in the edge preservation.
In this paper, an adaptive separable 2D wavelet transform is proposed. wavelet transforms are widely used in signal and imageprocessing due to its energy compaction property. Sparser representation corresponds to bet...
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In this paper, an adaptive separable 2D wavelet transform is proposed. wavelet transforms are widely used in signal and imageprocessing due to its energy compaction property. Sparser representation corresponds to better performance in compression, denoising, compressive sensing, sparse component analysis and many other applications. The proposed scheme results in more compact representation then fixed wavelet. Instead of the commonly used least squares criterion, least absolute deviation (LAD) is introduced. It results in more accurate adaptation resistant to outliers. The advantages of the proposed method have been shown on synthetic and real-world images.
In this study, we aimed to determine whether the medical image belongs to that class or not, using the textural features of medical images. The study was performed on the images in IRMA (image Retrieval in Medical App...
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ISBN:
(纸本)9781467373869
In this study, we aimed to determine whether the medical image belongs to that class or not, using the textural features of medical images. The study was performed on the images in IRMA (image Retrieval in Medical applications), the international database. After performing pre process on the our current medical images, discrete wavelet transform (DWT) was applied and then discrete cosine transform (DCT) was applied to each band components. After feature extraction, using of 1%, 3%, 5% and 7% of the obtained data were classified. K-Nearest neighbor algorithm (KNN) was used in the classification phase. The classificaiton performance was around 87%.
`Regularity' is a new criterion brought by wavelet theory over filter banks. It is therefore important to know whether this criterion is relevant for applications such as image compression, in comparison with othe...
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ISBN:
(纸本)0780309464
`Regularity' is a new criterion brought by wavelet theory over filter banks. It is therefore important to know whether this criterion is relevant for applications such as image compression, in comparison with other filter properties. The following problem is addressed: How do regularity, frequency selectivity and phase act upon the performance of a still image compression scheme using wavelet decomposition? Preliminary results are given for a simple compression scheme using orthonormal separable wavelet transforms, scalar quantization, rate/distortion optimization, various coding criteria, and a large number of `wavelet' filters with balanced regularity, frequency selectivity and phase.
This paper presents a satellite image compression scheme based on a post-processing of the wavelet transform of images. The bandelet transform is a directional post-processing of wavelet coefficients. Thanks to a low ...
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ISBN:
(纸本)9781424414833
This paper presents a satellite image compression scheme based on a post-processing of the wavelet transform of images. The bandelet transform is a directional post-processing of wavelet coefficients. Thanks to a low computational complexity, this transform is a good candidate for future on-board satellite image compression systems. First, we analyze the ability of the bandelets to exploit directional correlations between wavelet coefficients. This study leads to an improved post-processing with a better decorrelation of adjacent wavelet coefficients in the vertical or in the horizontal direction taking into account the wavelet subband orientations. To perform even better decorrelation, bases are also build by Principal Component Analysis (PCA). This results in an improved compression performance without increasing the computational complexity.
applications of image compression is important in terms of time and resource management considering factors such as require more time to send according to the size of image over the network and large amount of space i...
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ISBN:
(纸本)9781467373869
applications of image compression is important in terms of time and resource management considering factors such as require more time to send according to the size of image over the network and large amount of space is high dimensional data for storing images. In this study, a new approach can be using at image compression process will be introduced. Firstly, image subjected to discrete wavelet transform for extracting feature. Then multi-level threshold values will be find with Shanon entropy in the obtained image. The maximum value of objective function will be obtained with the help of cricket algorithm at the threshold values finding step. This algorithm is a meta-heuristic algorithm that based on population. The threshold values that obtained through algorithm using to compressing the images will be provided. At the end of the study, the image compression ratio, the proposed approach running on a standard test image will be given.
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.
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