Hardware designs that can support multiple standards are required for versatile media players. Since the proposed method encodes all the three colour components in single pass, the colour image encoding time is slightly higher than that of grey scale image coding but in contrast to three times in the existing colour image coding techniques.Д®fficient inverse transform architectures for multi-standard video coding applications The proposed technique generates two dynamic codebooks and two backup codebooks adaptively and use rate-distortion cost criteria to encode both the homogeneous and complex regions separately.

The integer-based orthogonal polynomials transform is then applied on the variable block sizes utilising the inter-correlation property of individual colour planes and interactions among the colour planes so as to reduce the vector dimension and hence the less computational cost. The homogeneous regions are encoded with fixed larger blocks and the complex regions are further divided into smaller block sizes for encoding as it gives the wealth of low-level information such as the high detail and high number of contrast edges. The input colour image is partitioned into fixed larger block sizes and the homogeneity/complexity of the local region is tested with the mean-normalised variance classifier. In this paper, a new adaptive vector quantisation with variable block size based on orthogonal polynomials is proposed for colour image coding. The experiment results demonstrate that the authors'method outperforms significantly CC interpolation in terms of both subjective and objective measures.ДЄn orthogonal polynomials transform-based variable block size adaptive vector quantisation for colour image coding The authorsвЂ™ method can preserve the sharp edges and details of images with notable suppression of the artefacts that usually occur with CC interpolation. The authors also give an estimation method of the strong edge for a missing pixel location, which guides the interpolation for the missing pixel. In this study, the authors propose a novel edge-directed CC interpolation scheme which can adapt to the varying edge structures of images. KeysвЂ™ cubic convolution (CC) interpolation method has become a standard in the image interpolation field, but CC interpolates indiscriminately the missing pixels in the horizontal or vertical direction and typically incurs blurring, blocking, ringing or other artefacts. It is also called image interpolation because it is usually implemented by interpolation. Image-zooming is a technique of producing a high-resolution image from its low-resolution counterpart. Image zooming using directional cubic convolution interpolation Various numerical experiments demonstrate that the effect of these errors is much more prominent in small images and, therefore the proposed method is suitable for applications involving small images, such as in optical character recognition and template-matching applications. The effect of the improved accuracy in the PHTs is analysed for rotation invariance, scale invariance and image noise. We propose a computational framework based on numerical integration approach that reduces the geometric error and the numerical integration error simultaneously. Numerical integration error is caused when the integration is approximated by zeroth-order summation. Geometric error is caused when a square image is mapped into a unit circular disk, which cannot exactly match the square domain.

PHTs suffer from geometric error and numerical integration error. Polar harmonic transforms (PHTs) are one of such image descriptors based on a set of orthogonal projection bases, which are better rated in comparison with other moments and transforms because they possess less redundant information. Invariant moments and transforms are a special kind of statistical measure designed to remain constant after some transformations, such as object rotation, scaling, translation or image illumination changes, in order to improve the reliability of a pattern recognition system.

Source: IET Image Processing, Volume 6,.

Accuracy and numerical stability of high-order polar harmonic transforms

Digital techniques volume 6