We present a novel technique for efficient coding of texture to be mapped on 3D landscapes. The technique enables to stream the data across the network using a back-channel. The use of Wavelet and Discrete Cosine Transforms is investigated and compared. This technology has been proposed has a tool for the emerging MPEG-4 standard.

A reversible data hiding scheme based on integer DWT and histogram modification is proposed. In the scheme, the cover media is firstly transformed by Integer DWT (Discrete Wavelet Transformation); then information is embedded through the modification of histograms of the middle and high frequency sub-bands of the DWT coefficients. In order to increase the embedding capacity, a multi-level schem...

Images are often compressed to reduce storage. In order to avoid full decoding in image retrieval, features extracted directly from transformed data have been investigated. The popularity of JPEG and JPEG2000 motivates us to investigate a fast conversion scheme from block-based discrete cosine transform (BDCT) to wavelet domain so that similar features can be extracted from the two different do...

ORTHOGONAL AND SYMMETRIC HAAR WAVELETS ON THE THREE-DIMENSIONAL BALL Andy Chow Master of Science Graduate Department of Computer Science University of Toronto 2010 Spherical signals can be found in a wide range of fields, including astronomy, computer graphics, medical imaging and geoscience. An efficient and accurate representation of spherical signals is therefore essential for many applicati...

Current research in image compression (wavelets, local trigono-metric bases, JPEG, etc.) centres on adaptive coding of the grey levels of the image. These methods may be described as using band-limiting procedures with a band-limit that depends on the local properties of the image. This paper looks at the non-adaptive use of Discrete Cosine Transforms in blocks, with uniform band-limits over th...

In this paper image compression using hybrid wavelet transform is proposed. Hybrid wavelet transform matrix is formed using two component orthogonal transforms. One is base transform which contributes to global features of an image and another transform contributes to local features. Here base transform is varied to observe its effect on image quality at different compression ratios. Different ...

Discrete cosine transform emerged as a popular mathematical tool in past decade and widely used in image compression algorithm due to its high energy compaction capacity. But this energy compaction has some limitation in blocking artifacts that overcome by another mathematical tool wavelet transform based compression which have both frequency and spatial component study at same time. In this pa...

The paper contains a brief description of fractal image compression methods with sample compression results. We also present comparative results between two fractal schemes, discrete cosine transform, and a wavelet method. We show that, with the PSNR as a measure of image quality, some fractal schemes perform best over the range of compressions of most interest.

here are several domain transform like Fourier, sine, cosine and wavelet transform to processes an image. But the problem with these transform are inefficient to solve certain problem. Fractional Fourier transform gives extra degree of flexibility. It helps to improve image such as Image sharpness, filter and watermark. Keywords— Image processing, Fractional Fourier transform, FrFT, Image blurr...

In the recent growth of data intensive and multimedia based applications, efficient image compression solutions are becoming critical. The main objective of Image Compression is to reduce redundancy of the data and improve the efficiency. The main techniques used are Fourier Analysis, Discrete Cosine Transform vector quantization method, sub-band coding method. The drawbacks in the above method...