参考源码

https://github.com/michaelliao/learn-python3/blob/master/samples/packages/pil/use_pil_resize.py

https://github.com/michaelliao/learn-python3/blob/master/samples/packages/pil/use_pil_blur.py

https://github.com/michaelliao/learn-python3/blob/master/samples/packages/pil/use_pil_draw.py