Background issue of holes

[chiba1sonny]

Thanks for the great work.
I have a question about the annotation of holes.
If I annotated a hole as "background", and converted the JSON data to Voc data, is this hole(labeled "background") and actual background(unlabelled) is same?

like in this image, are part 1 and part 2 the same?

[wkentaro]

You need to introduce an additional class.
In the example, __ignore__ class is there in addition to _background_.
https://github.com/wkentaro/labelme/blob/main/examples/semantic_segmentation/labels.txt
In your case, I guess the hole can be categorized as either __ignore__ or hole.

[chiba1sonny]

Thanks for your kind reply.