Novel wavelet transform based schemes for coding still images and image sequences are presented. The still image codec uses a new efficient adaptive bit-plane run-length coding of the wavelet transform coefficients of...
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We present in the following work, a multiscale edge detection algorithm whose aim is to detect edges of any slope. Our work is based on a generalization of the Canny-Deriche filter, modelized by a more realistic edge ...
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ISBN:
(纸本)0819416274
We present in the following work, a multiscale edge detection algorithm whose aim is to detect edges of any slope. Our work is based on a generalization of the Canny-Deriche filter, modelized by a more realistic edge than the traditional step shape edge. The filter impulse response is used to generate a frame of wavelets. For the merging of the wavelet coefficients, we use a geometrical classifier developed in our laboratory. The segmentation system thus set up and after the training phase does not require any adjustment nor parameter. The main original property of this algorithm is that it leads to a binary edge image without any threshold setting.
This paper attempts to synthesize the wavelet theories to simple design procedures so that applied researchers can readily select or design wavelets with chosen characteristics for particular applications. The paper h...
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This paper attempts to synthesize the wavelet theories to simple design procedures so that applied researchers can readily select or design wavelets with chosen characteristics for particular applications. The paper highlights the importance of the four most desirable characteristics of wavelets for use in digital signalprocessing, namely- orthonormality, symmetry, compactness and smoothness. Some of these characteristics are mutually exclusive and require design compromise. Examples of some most popular wavelets and the effects their characteristics have on the quality of the reconstructed image in wavelet-based image coding, are given for comparison.
Textured image is considered as the repetition of some primitives with a certain rule of displacement, thus every region in the image has different periodic structure. The segmentation is realized by its self-imaging ...
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ISBN:
(纸本)0819416274
Textured image is considered as the repetition of some primitives with a certain rule of displacement, thus every region in the image has different periodic structure. The segmentation is realized by its self-imaging effect. A series of Fresnel images can be obtained at the fractional Talbot distances depended on the periodicity of the original. All these images are a summation of the Fourier frequency modulated by a phase factor, which related with the fractional Talbot distance. Therefore, these images can be considered as the multichannel Talbot transform of the original image and represent the texture features to a certain extent. By comparing these images, different texture regions are segregated. Theoretical analysis and primitive experimental results are presented.
Presents a multiscale, statistically-based algorithm for the detection and characterization of localized anomalies in a medium based upon observations of scattered energy obtained along the boundaries of the region. T...
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wavelet transform has recently emerged as a promising technique for video processingapplications due to its flexibility in representing nonstationary video signals. In this paper, we propose a fast multiresolution mo...
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ISBN:
(纸本)081941638X
wavelet transform has recently emerged as a promising technique for video processingapplications due to its flexibility in representing nonstationary video signals. In this paper, we propose a fast multiresolution motion estimation (FMRME) scheme based on the wavelet transform for video compression. In FMRME, the set of orientation subimages at each level of the wavelet pyramid are first combined together into a single (all-orientation) sub-image, and then the motion estimation is performed on the newly formed subimage. This contrasts with the MRME scheme (recently reported in the literature) where motion estimation is separately performed on all the individual wavelet subimages. The motion vectors of an all-orientation subimage at a lower level are predicted from the motion vectors at the higher (preceding) level and are refined at each step. The proposed scheme reduces the search time for motion vectors by 66% compared to MRME. In addition, the FMRME scheme has the advantage of significantly reduced side information for the description of motion vectors. Simulations show that the FMRME scheme has considerable reductions in the bit rate which results to significant improvements in coding performance of the FMRME based wavelet coding compared to the MRME based wavelet coding for video compression.
Dynamic bit allocation directly impacts the overall coding performance in block transform (e.g., DCT, Hadamard, etc.) coding, subband coding, and wavelet coding. In very low bit rate coding (such as the evolving MPEG-...
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Pyramid image coding is a natural coding scheme for applications where progressive transmission is desired. In this kind of coder, versions of the original image at several resolution levels are formed by successive f...
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A novel formulation of imageprocessing operations in the wavelet domain is presented which directly associates multiresolution with multichannel imageprocessing. The formation of the multiresolution image is express...
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A novel formulation of imageprocessing operations in the wavelet domain is presented which directly associates multiresolution with multichannel imageprocessing. The formation of the multiresolution image is expressed as an operator on the image domain that transforms block-circulant structures into partially-block-circulant structures. The proposed implementation relaxes the stationarity and space-invariance assumptions in the image domain and introduces new operator structures for the implementation of single-channel algorithms which take advantage of the correlation structure in the wavelet domain. Based on this structure, the authors discuss the estimation of the power spectrum in the wavelet domain. image restoration examples using the linear minimum mean square error filter show significant improvement achieved by the proposed approach over the conventional discrete Fourier transform (DFT) implementation.< >
Novel wavelet transform based schemes for coding still images and image sequences are presented. The still image codec uses a new efficient adaptive bit-plane run-length coding of the wavelet transform coefficients of...
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Novel wavelet transform based schemes for coding still images and image sequences are presented. The still image codec uses a new efficient adaptive bit-plane run-length coding of the wavelet transform coefficients of images. The main merit of this coding scheme is its simplicity requiring no training or storage of codebooks and it outperforms the JPEG at low bit-rate. For image sequence coding, a very low bit-rate sub-band motion estimation/compensation video codec designed for colour video conferencing applications is presented. A full system with buffer feedback control is designed. Simulation results of transmitting colour image sequences at 9.6 to 19.2 kbit/s are given.< >
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