title: How to set input shape of a trained model in Keras?
body: <p>I am new to TensorFlow and Keras, and I have a trained model that has structure: </p>
  
  <pre><code>_________________________________________________________________ 
  Layer (type)                 Output Shape              Param #   
  ================================================================= 
  input_1 (InputLayer)         (None, 128, 128, 3)       0         
  _________________________________________________________________ 
  conv1 (Conv2D)               (None, 64, 64, 8)         216       
  _________________________________________________________________
  ...
  </code></pre>
  
  <p>For some reason (convert model into other CNN framework) I have to fix the batch number from <code>None</code> to <code>1</code> to make it work, so that the input shape would be: (1,128,128,3). The desired structure would be:</p>
  
  <pre><code>_________________________________________________________________ 
  Layer (type)                 Output Shape              Param #   
  ================================================================= 
  input_1 (InputLayer)         (1, 128, 128, 3)       0         
  _________________________________________________________________ 
  conv1 (Conv2D)               (1, 64, 64, 8)         216       
  _________________________________________________________________ 
  ...
  </code></pre>
  
  <p>I have tried to replace or insert a new Input layer but it didn't work. Any hint or tips would be appreciated!</p>