#aspect-ratio

d2l generates an anchor box of scale $s \in (0, 1]$ and aspect ratio $r$ (width / height) with width $ws\sqrt{r}$ and height $hs/\sqrt{r}$, where $w$ and $h$ are the image width and height. For a $400 \times 400$ image, $s = 0.5$ and $r = 2$, what is the anchor's width in pixels?