Technical Report CIS-2009-10

Title: Affine-invariant spatial vocabularies
Authors: Alex. M. Bronstein and Michael. M. Bronstein
Abstract: Invariant image descriptors play an important role in many computer vision and pattern recognition problems such as image search and retrieval. A dominant paradigm today is that of \bags of features", a representation of images as distributions of primitive visual elements. The main disadvantage of this approach is the loss of spatial relations between features, whi ch often carry important information about the image. In this paper, we show how to construct spatially-sensitive image descriptors in which both the features and their relation are a±ne-invariant. Our construction is based on a vocabulary of pairs of features coupled with a vocabulary of invariant spatial relations between the features. Experimental results show the advantage of our approach in image retrieval applications.
CopyrightThe above paper is copyright by the Technion, Author(s), or others. Please contact the author(s) for more information

Remark: Any link to this technical report should be to this page (, rather than to the URL of the PDF files directly. The latter URLs may change without notice.

To the list of the CIS technical reports of 2009
To the main CS technical reports page

Computer science department, Technion