from fastai2.vision.all import *
from fastai2.vision.widgets import *

source = untar_data(URLs.MNIST_TINY)

dblock = DataBlock((ImageBlock(PILImageBW), CategoryBlock), get_items=get_image_files,
                   splitter=GrandparentSplitter(),
                   get_y=parent_label,
                   batch_tfms=[Normalize.from_stats(*imagenet_stats)])

dls = dblock.dataloaders(source)
dls.show_batch(max_n=4, nrows=1)

learn = cnn_learner(dls, resnet18, metrics=[accuracy])
learn.fine_tune(1)

epoch	train_loss	valid_loss	accuracy	time
0	0.913778	0.274617	0.917024	00:02

epoch	train_loss	valid_loss	accuracy	time
0	0.383067	0.251726	0.902718	00:01

cleaner = ImageClassifierCleaner(learn)
cleaner

ImageClassifierCleaner doesn't actually do the deleting or changing of labels for you; it just returns the indices of items to change. So, for instance, to delete (unlink) all images selected for deletion, we would run:

for idx in cleaner.delete(): cleaner.fns[idx].unlink()

To move images where we've selected a different category, we would run:

for idx,cat in cleaner.change(): shutil.move(cleaner.fns[idx], source/cat)