In a nutshell: build and test a classifier for these handwritten characters, using a decision tree and the SVM algorithm that we will study today. You may not use any canned machine-learning package, like sklearn: your code must all be written from scratch except for solving the quadratic programming problem with cvxopt.
Cross validation: Take some "training" subset of the PNG images that you think you might to use to to develop a classifier, and another subset that you will use to test the quality of your classifier.