Yeah, it's not always easy to see whether it's a building, and whether the outline is correct. Also: should I say it's correct when it's only roughly correct, o

Yeah, it's not always easy to see whether it's a building, and whether the outline is correct. Also: should I say it's correct when it's only roughly correct, or should it be perfect? I think you'll get a lot of noise from this. But according to the presentation, they analyze that noise and manage to use it to improve the data.