In this paper we present a unified system for the extraction, representation and query of spatially localized color and texture regions. The system utilizes a back-projection of binary feature sets to identify and extract prominent regions. The binary feature sets provide an effective and easily indexable representation of color and texture. We also provide a mechanism for integrating features by combining the binary color and texture feature sets. This enables the extraction and representation of joint color and texture regions. Since all extracted regions are spatially localized, in image database queries the user can specify the locations and spatial boundaries of regions. We present the unified color and texture back-projection method and describe its implementation in the VisualSEEk content-based image retrieval system.