Pre-trained mode layer, the description of the “Input Shape” parameter says
Optional shape tuple, only to be specified if include_top
is false (otherwise the input shape has to be (224, 224, 3)
(with tf
dim ordering) or (3, 224, 244)
(with th
dim ordering). it should have exactly 3 inputs channels, and width and height should be no smaller than 197. e.g. (200, 200, 3)
would be one valid value.
When include_top
is false, not specifying the input shape does not stop the Model to be valid and it can be trained. It seem like DLS automatically fills that parameter.