Texture segmentation is a significant and primary issue in texture analysis. It is concerned with automatically determining the boundaries between various textured regions in an image. In this paper we propose a region-based method for textured image segmentation. First, we consider the basic problem of texel identification and the determination of its shape. Further, we describe the texture characterized by a texel, that is we identify the equivalence class of a certain structural description. Finally, we improve the accuracy of the boundaries provided by the segmentation algorithm using least squares spline approximation.