Underlying most digital signal processing (DSP) algorithms is the group Z/N of integers modulo N , which is taken as the data indexing set. Recently, An and Tolimieri [1] considered a different class of index set mappings, which arise when the underlying group is nonabelian, and successfully apply them to 2D image data. Advantages of indexing signals with nonabelian groups are not limited to im...

Retrieval of multimedia has become a requirement for many contemporary information systems. These systems need to provide browsing, querying, navigation, and, sometimes, composition capabilities involving various forms of media. In this survey, we review techniques for text, image, audio and video retrieval. We first look at indexing and retrieval techniques for text, audio, image and video. We...

Image patches of different roughness are likely to have different perceptual significance. In this paper, we introduce a method, which separates an image into layers, each of which retains only pixels in areas with similar spectral distribution characteristics. Simple color indexing is used to index the layers individually. By indexing the layers separately, we are implicitly associating the in...

This paper presents a new application of a well-studied image coding technique, namely block truncation coding (BTC). It is shown that BTC can not only be used for compressing color images, it can also be conveniently used for content-based image retrieval from image databases. From the BTC compressed stream (without performing decoding), we derive two image content description features, one te...

We propose a color-based image descriptor that can be used for image indexing based on high-level semantic concepts. The descriptor is based on Kobayashi’s Color Image Scale, which is a system that includes 130 basic colors combined in 1170 three-color combinations. Each combination is labeled with one of 180 high-level semantic concepts, like ”elegant”, ”romantic”, ”provocative”, etc. Moreover...

This paper proposes the use of a vector of color histogram peaks as an efficient and effective way for many image indexing problems. It shows that histogram peaks are more stable than general histogram bins when there are variation of scale and/or scale. We also introduce the structure of a room recognition system which applies this indexing technique to omni-directional images of rooms. Experi...

The digital libraries of the future will include not only (ASCII) text information but scanned paper documents as well as still photographs and videos. There is, therefore, a need to index and retrieve information from such multi-media collections. The Center for Intelligent Information Retrieval (CIIR) has a number of projects to index and retrieve multi-media information. These include: 1. Th...

Image retrieval by content is characterized by the ability of a system to retrieve relevant images based on their visual or their semantic contents. In this paper, we survey key contributions in the medical imaging area. We centre our attention on one related sub-fields: the semantic indexing process. We describe limitations of visual approaches and provide taxonomy for semantic ones with an em...