Figure 7: Processing low TRAP signals through cascaded applications of Otsu’s method. (A) Original scanned image (B) Outcome from the application of Otsu’s method on Figure 7A. It did not separate the background pixels inside the femur, and most of the background pixels selected. (C) Outcome from the second application of Otsu’s method on the pixels of Figure 7A selected by Figure 7B. The background pixels are separated and the TRAP signal are selected.