Volumetric Texture Analysis

Texture analysis in 2D has been well studied, but many 3D applications in Medical Imaging, Stratigraphy or Crystallography, would benefit from 3D analysis instead of the traditional, slice-by-slice approach.

Segmentation of bones
During my PhD at Warwick University I developed a Multiresolution Volumetric Texture Segmentation (M-VTS) algorithm which allowed the analysis of texture through 3D frequency filtering. The method ology extracted textural measurements from the Fourier domain of the data via subband filtering using an Orientation Pyramid [1].

A novel Bhattacharyya space, based on the Bhattacharyya distance was proposed for selecting the most discriminant measurements and producing a compact feature space. Each dimension of the feature space was used to form the lowest level of a Quad Tree. At the highest level of the tree, new positional features were added to improve the contiguity of the classification. The classified space was then projected to lower levels of the tree where a boundary refinement procedure is performed with a 3D equivalent of butterfly filters.

The performance of M-VTS was tested in 2D by classifying a set of standard texture images. M-VTS yields lower misclassification rates than reported elsewhere.

Classification of 2D textures


The algorithm was tested in 3D with artificial isotropic data and three Magnetic Resonance Imaging sets of human knees with encouraging results. The regions segmented from the knees correspond to anatomical structures that could be used as a starting point for other measurements. By way of example, we demonstrate successful cartilage extraction.

Subband filtering


Cartilage segmentation


Three publications arose from this work:

  • an in-depth analysis of extraction of textural features from volumetric data will soon apper here:
Reyes-Aldasoro, C.C. and A. Bhalerao, Volumetric Texture Analysis in Biomedical Imaging, in Biomedical Diagnostics and Clinical Technologies: Applying High-Performance Cluster and Grid Computing, Pereira, M., Freire, M. (Eds.) 

  •  the novel Bhattacharyya space and its application in 2D texture

coverPatRec
Reyes-Aldasoro, C.C.
, and A. Bhalerao,
The Bhattacharyya space for feature selection and its application to texture segmentation
,
 Pattern Recognition, (2006)
Vol. 39, Issue 5, May 2006, pp. 812-826. 




  • and the volumetric segmentation in 3D MRI images:


cover TMI

Reyes-Aldasoro, C.C., and A. Bhalerao,
Volumetric Texture Segmentation by Discriminant Feature Selection and Multiresolution Classification,
IEEE Trans. on Medical Imaging (2007)
Vol. 25, No. 1, pp. 1-14.



  • all the datasets and algorithms are available on an as-is basis in my old website at Warwick: