Can't do Segmentation: CUDA error: device-side assert triggered

Part 1 (2019)
5

I have found the solution. The problem is that my masks have the following values: [0, 255], and this is not supported by default by fast.ai. The problem is that the fast.ai function open_mask works with small mask pixel values like 0,1,2,3 by default. This function is called by the SegmentationLabelList class. To work with 255 values we should call the function open_mask with div=True: open_mask(fn, div=True). It divides the mask pixel values by 255.

In order to change the default behaviour of open_mask, I did the following:

class SegLabelListCustom(SegmentationLabelList):
    def open(self, fn): return open_mask(fn, div=True)

class SegItemListCustom(SegmentationItemList):
    _label_cls = SegLabelListCustom

codes = ['0','1']
src = (SegItemListCustom.from_folder(path_img)
       .random_split_by_pct(valid_pct=0.2, seed=33)
       .label_from_func(get_y_fn, classes=codes))

data = (src.transform(get_transforms(), size=size, tfm_y=True)
        .databunch(bs=bs)
        .normalize(imagenet_stats))

Hope this helps. Thank you for your replies!

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