In this chapter, you will need the following:

- In Exercise 1:
 We present several approaches for tracing contours in images. We give here in the main file SignifLevLines.m (in which you need the function  bestblocks.m) the MatLab code for one of them: the significant level lines.  You can also find many available codes in C on the MegaWave2 (a free software intended for image processing) website:  .

- In Exercise 5:
 We propose a code for computing the medial axis with MatLab. You can find it here.