Hi!
When comparing the transform you defined and the error you got, it seems like your input is only one layer while your transform expects three layers (looking at the normalization-part):



 Caroline_Barcelos:

transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225])


You should change your normalization so that it only has one value for the mean and one for standard deviation. Then the transform should be valid and you can just apply it to your converted numpy array