I’m trying to make a unet generate images. Regardless of what I do, fine tuning shows a valid_loss of None, and warns “Your generator is empty.” However, I’ve verified that the dataloader is providing batches properly.
I think the issue may be associated with the loss function, but I’m not sure. Does anyone have any idea what I’m doing wrong or what I can do to troubleshoot?
from fastai.vision.all import * from fastai.imports import * from fastai.vision.core import * from fastai.vision.data import * #kitchen sink from pathlib import Path def labelFunc(f): return Path("outputPics/" + f.name) img = DataBlock(blocks=(ImageBlock(cls=PILImage), ImageBlock(cls=PILImage)), get_items = get_image_files, get_y = labelFunc, splitter=RandomSplitter(), item_tfms=Resize(120, 200), batch_tfms=aug_transforms() ) dls = img.dataloaders(Path("inputPics/"), bs=2) dls.show_batch() learn = unet_learner(dls, models.resnet18, n_out=3, loss_func=nn.MSELoss()) learn.fine_tune(2, 3e-3)