title: Keras image augmentation for images with two channels
body: <p>I performed data augmentation for images with two channels. My data set is formatted in the shape of <code>(image_Numbers, image_height, image_weights, image_channels)</code>, where <code>image_channels = 2</code>. </p>
  
  <p>In performing data augmentation using <code>datagen</code> (created by <code>ImageDataGenerator</code>), a userwarining message is generated:</p>
  
  <pre><code>UserWarning: NumpyArrayIterator is set to use the data format convention     
  "channels_last" (channels on axis 3), 
  i.e. expected either 1, 3 or 4 channels on axis 3. 
  However, it was passed an array with shape (1, 150, 150, 2) (2 channels).
  </code></pre>
  
  <p>Does the warning imply the data augmentation was unsuccessful? Was it only performed for one channel images? If so, how to perform data augmentation for two-channels of images (not one channel this time and then concatenation)?</p>