looks like the default loader converts to ‘RGB’:

  
      github.com
  
  
    pytorch/vision/blob/master/torchvision/datasets/folder.py#L42-L46 305

                item = (path, class_to_idx[target])
                images.append(item)


return images





  
  
    
    
  
  


By default with ImageLoader you can specify your own loader: https://github.com/pytorch/vision/blob/master/torchvision/datasets/folder.py#L92 873