Can I choose not to apply a transform to my y values in fastai v2?

fastai fastai dev
3

Great idea, thanks!

In my case I’ve been applying the transformation to the PILImage’s one at a time (as opposed to a batch of tensors). So for any future readers, the changes I made were:

Introduce a new PIL Image type:

class PILImageInput(PILImage): pass

Make sure my transform handles that type in encodes()

class RandomCutout(RandTransform):

    def __init__(self, min_n_holes=5, max_n_holes=10, min_length=5, max_length=50, **kwargs):
        super().__init__(**kwargs)
        ....

    def encodes(self, x:PILImageInput):
        # Here we accept only PILImageInput (this type matters in fastai2)
        ...

Then just pass this transform to item_tfms when creating a databunch:

databunch = data.databunch(images_path, 
                           bs=10, 
                           item_tfms=[RandomCutout()], # Pass RandomCutout to item_tfms
                           batch_tfms=[*aug_transforms(size=160, max_warp=0, max_rotate=0)])
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