Why do anchor boxes need to be pre-defined?

[ai_curious]

@Charlypocket

Why can’t the height and width of the anchor box be learnt

They are. Not exactly as bounding boxes, though. Bounding boxes are learned through supervised learning. Anchor boxes are learned through unsupervised learning. See if this thread helps…

Deriving YOLO anchor boxes

Deriving Anchor Boxes for YOLO One area of recurring questions about YOLO is anchor boxes, introduced with the second 2016 paper, YOLO9000 aka YOLO v2, as an optimization to help improve model stability during training. I’ll defer discussion of the role they play for now and just cover how they are created. Once you see what they are, I think it will be easier to understand how they are used. The Dataset I worked with the Berkeley DeepDrive 100K dataset (BDD). To keep the size manageable, I u…