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An improved multi-focus image fusion method based on wavelet transform is proposed. Firstly, multi-scale decomposition is performed on source images using wavelet transform to get high-frequency and low-frequency sub-images. And then, a method based on neighboring region variance weighted-average is applied to high-frequency sub-image to get the high-frequency fusion coefficient; and a method based...
It is difficult to get high compression ratio and good reconstructed image by conventional methods; we give a new method of compression on medical image. It is to decompose and reconstruct the medical image by wavelet packet. Before the construction the image, use neural network in place of other coding method to code the coefficients in the wavelet packet domain. By using the Kohonen's neural network...
In this paper, an improved technique for evolving wavelet coefficients refined for compression and reconstruction of fingerprint images is presented. The FBI fingerprint compression standard uses the cdf 9/7 wavelet filter coefficients. Lifting scheme is an efficient way to represent classical wavelets with fewer filter coefficients. Here Genetic algorithm (GA) is used to evolve better lifting filter...
The objective of this paper is to implement the concept of wavelet based image compression to gray scale images using different techniques. The techniques involved in the comparison process are EZW and WDR. These techniques are more efficient and provide a better quality in the image. In compression, wavelets have shown a good adaptability to a wide range of data, while being of reasonable complexity...
This paper proposes a distortionless image data hiding algorithm based on integer wavelet transform that can hide data into the original image .The data can be retrieved and the original image can be recovered without any distortion after the hidden data are extracted. This algorithm hides data into one or more middle bitplane(s) of the integer wavelet transform coefficients in the LH, HL and HH frequency...
Compressive Sensing is a new theory to simultaneous sensing and compression. It enables a potentially large reduction in the sampling and computation costs for signals based on them having sparse representation in some basis. Many wavelet transformations were used in CS, such as Haar, db4, db6 and db8 wavelets. We test several wavelet basis from Daubechies and Biorthogonal family using Bayesian wavelet-tree...
In this work we propose a modified version of the BM3D algorithm recently introduced by Dabov et al. for the denoising of images corrupted by additive white Gaussian noise. The original technique performs a multipoint filtering, where the nonlocal approach is combined with the wavelet shrinkage of a 3D cube composed by similar patches collected by means of block-matching. Our improvement concerns...
A variety of wavelet transform methods have been introduced to remove noise from images. However, many of these algorithms remove the fine details and smooth the structures of the image when removing noise. The wavelet coefficient magnitude sum (WCMS) algorithm can preserve edges, but it is at the expense of removing noise. The Non-Local means algorithm can removing noise effective. But it tend to...
In this paper, a new image denoising algorithm based on dual-tree complex wavelet transform (DTCWT) is proposed, in which directional windows are chosen as local neighborhood to estimate the variance. For the different subbands within the same scale, better estimation about energy cluster can obtained by ellipse windows than square windows, and the sizes of the ellipse windows for different scales...
Watermarking algorithm based on wavelet transform is a main field in digital watermarking study. With watermarking property, the paper investigates the distributed feature of the wavelet coefficient and analyzes the effect of typical attacks to the wavelet coefficient. Through the experiment of different texture and gray images, the paper analyzes the relation between embedding intensity and watermarking...
This paper presents an efficient fuzzy possibilistic code book design for vector quantization in the wavelet packet domain. Wavelet packet tree (WPT) methodology is applied to the whole image. The sub blocks of the input image are decomposed into two level WPT where all coefficients of LL band and the approximation coefficients of LH, HL & HH bands are quantized using the proposed vector quantizer...
Copyright protection is an important aspect of the management of resources in any eBusiness dealing with digital multimedia distribution. Two of its main aims are to guarantee that any use of the media is in accordance to its license and to assert the ownership of the media. The solution to copyright protection consists of many technologies, one of which is watermarking. In the case of copyright protection,...
Medical image compression techniques should give high compression ratios apart from preserving vital information in medical images. In this paper we propose a compression technique for four-dimensional functional Magnetic Resonance Images (fMRI). The proposed technique uses bandelet transform to capture the anisotropic regularity of edge structures apart from capturing regularity information from...
In this paper we propose a novel iterative algorithm for wavelet-based image denoising following a Maximum a Posteriori (MAP) approach. The wavelet shrinkage problem is modeled according to the Bayesian paradigm, providing a strong and extremely flexible framework for solving general image denoising problems. To approximate the MAP estimator, we propose GSAShrink, a modified version of a known combinatorial...
In this paper we propose a steganography technique based on Stantlet transform and T-codes. The Stantlet transform are wavelet-like transforms that provides better time localization and signal compression than the conventional discrete cosine transforms (DCT) and discrete Haar-wavelet transforms. T-codes are used for better embedding capacity and decoding efficiency. The proposed method first encodes...
This paper presents a new lossless data hiding method for digital images using integer wavelet transform and threshold embedding technique. Data are embedded into the least significant bit-plane (LSB) of high frequency CDF (2, 2) integer wavelet coefficients whose magnitudes are smaller than a certain predefined threshold. Histogram modification is applied as a preprocessing to prevent overflow/underflow...
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