Regions /patterns in images that creates classification I am  having  some images on which  I   trained some neural   network  models in order to  do classification( binary  task).
I am interested  of a  method    to identify  some patterns  or regions  in those images  that are  influencial  the classification   part in  other words  what  regions or  what patterns are formed  for a particular  class.
I think visualizing convolutional neural networks is what you want.

CS231n is a good place to start, here is a step-by-step guide about how to visualize the activations, first-layer weights, and shows how to retrieve images which maximally activate a neuron.

Also there's a demo which visualized multiple convnets (including ResNet50, Inception v3, etc). You may learn a lot from this demo (at least I do).

If you're interesting in details, this well-known paper may help you.