learning lenet5
- https://medium.com/analytics-vidhya/lenet-with-tensorflow-a35da0d503df
- https://medium.com/@mgazar/lenet-5-in-9-lines-of-code-using-keras-ac99294c8086
https://www.tensorflow.org/api_docs/python/tf/pad
paddings is an integer tensor with shape [n, 2], where n is the rank of tensor.
each dimension D
- paddings[D, 0]: add before tensor
- paddings[D, 1]: add after tensor