added SA-1B dataset class

[simoneangarano]

I noticed a custom PyTorch dataset class was missing, and I thought it could also be useful for other users.
The class simply inherits from ImageFolder and loads decoded masks as targets.
Enjoy!

Simone Angarano
PhD Student at Politecnico di Torino, Interdepartmental Center for Service Robotics (PIC4SeR)
Email: simone.angarano@polito.it
Website: simoneangarano.github.io

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[FrankFundel]

SA-1B does not include classes. Should use custom Dataset instead of ImageFolder.

[simoneangarano]

SA-1B does not include classes. Should use custom Dataset instead of ImageFolder.

It's up to you; this version returns the list of masks without any assigned class, and it does the job.

[sborse3]

Hi @simoneangarano , I found initializing this dataloader quite slow, as SA-1B is huge. Any workaround you would suggest?

[simoneangarano]

Hi @sborse3 ,
Unfortunately, the dataset is huge (11M images), so I don't think there's a workaround for that...
However, the DataLoader should load only a batch at a time in memory. Just use a smaller batch size to load fewer samples at a time.