Data augmentation per patch (not per image)

[jmlipman]

Hi,

Does MONAI apply data augmentation per image or per patch? I would say that when dealing with small images (say, 300x300x300), it probably makes sense to apply DA for each image. However, when dealing with a few very-large images (say, 3000x3000x300), it probably makes more sense to apply DA per patch as you will read each image only a few times. In case DA is applied per image, do you think it would be easy to modify MONAI to do it patch-wise?

Thanks!

[KumoLiu]

Hi @jmlipman, typically, once all non-random transforms have been applied and the data has been cropped to the patches, we perform data augmentation. And if you used CacheDataset, it will cache deterministic transforms' result during training.
https://github.com/Project-MONAI/MONAI/blob/82cd668c4dcb23d36beeb432cc0aa04b9e0a1b3c/monai/data/dataset.py#L695

Thanks!