In this paper, the quaternion Bessel-Fourier moments are introduced. The significance of phase information in quaternion Bessel-Fourier moments is investigated and an accurate estimation method for rotation angle is described. Furthermore, a new set of invariant descriptors based on the magnitude and the phase information of quaternion Bessel-Fourier moments is derived. Experimental results sho...

Audio-visual documents obtained from German TV news are classified according to the IPTC topic categorization scheme. To this end usual text classification techniques are adapted to speech, video, and non-speech audio. For each of the three modalities word analogues are generated: sequences of syllables for speech, “video words” based on low level color features (color moments, color correlogra...

The main objective of this paper is to develop a simple technique for contrast enhancement of monochrome and color images using Discrete Dual Hahn (DDH) moments. The basic idea of our approach is to measure a local contrast at each band of a DDH moment matrix and use it to modify them. These modified moments are used to construct the enhanced image by taking the inverse DDH moment transform. Fo...

Retrieving images from large and varied repositories using visual contents has been one of major research items, but a challenging task in the image management community. In this paper we present an efficient approach for region-based image classification and retrieval using a fast multi-level neural network model. The advantages of this neural model in image classification and retrieval domain...

We describe two new color indexing techniques. The rst one is a more robust version of the commonly used color histogram indexing. In the index we store the cumulative color histograms. The L 1-, L 2-, or L 1-distance between two cumulative color histograms can be used to deene a similarity measure of these two color distributions. We show that while this method produces only slightly better re...

This paper describes how low-level statistical visual features can be analyzed in our content-based image retrieval system named PicSOM. The lowlevel visual features used in the system are all statistical by nature. They include average color, color moments, contrast-type textural feature, and edge histogram and Fourier transform based shape features. Other features can be added easily. A genui...

So far, plant identification has challenges for several researchers. Various methods and features have been proposed. However, there are still many approaches could be investigated to develop robust plant identification systems. This paper reports several experiments in using Zernike moments to build foliage plant identification systems. In this case, Zernike moments were combined with other fe...

In this study an efficient and accurate algorithm is proposed for Content-Based Image Retrieval (CBIR). The CBIR is performed in two steps: features extraction in images and similarity measurement for searching of similar images in image database. For efficient and effective CBIR system the features extraction must be fast and the searching must be accurate. In the proposed algorithm, the effec...

Content-based image retrieval (CBIR) systems normally return the retrieval results according to the similarity between features extracted from the query and candidate images. In certain circumstances, however users are most qualified to specify the query “content” or objects(e.g., Eiffel Tower) of their interest , not the computer and only wish to retrieve images containing relevant objects, wh...

In this paper, we propose a type of joint feature with geometric parameters and color moments to represent the speaking-mouth frames for image-based visual speech synthesis systems. Based on FDP around the mouth area, the geometric feature is obtained by computing Euclidean distances to describe the width of the speaking mouth, the height of the outer and inner lips and the distances between th...