I am confused by the equations for bounding boxes I find online. Some articles say that
box_width = anchor_width * exp(residual_value_of_box_width))
and the coordinates have a sigmoid function.
But Darknet code and GitHub have equations dividing coordinates and box width with image width.
For example, https://github.com/AlexeyAB/darknet/blob/master/build/darknet/x64/data/voc/voc_label.py
def convert(size, box): dw = 1./size dh = 1./size x = (box + box)/2.0 y = (box + box)/2.0 w = box - box h = box - box x = x*dw w = w*dw y = y*dh h = h*dh return (x,y,w,h)
If the image width is used, then what is the use of anchor box width/height values in
yolov3.cfg file? I can't find where it has been used in the source code other than generate the anchors file.