Figure 2.

The illustration of filter bank and texton map (a) first to sixth rows: even $f_{{\theta }_t}^e$ and odd $f_{{\theta }_t}^o$ filter bank consisting of one scale and six orientations; seventh row: center-surround filter f^DoG. (b) The original image. (c) The texton map derived from a universal dictionary. (d) The texton map created using the proposed approach. (e) Zoom-in view of the region inside the white square outlined in (d). The ground truth tumor boundary indicated in dark color (green in online version), is overlaid to all texton maps.