In the following figure, point $C$, $D$ and $E$ are the middle points of line segment $AB$, $AC$ and $BC$, with the length of line segment $AB$ as $4$. Additionally, 6 semi-circles are drawn with diameters as $AD$, $AC$, $AE$, $DB$, $CD$ and $EB$. Find the area of each colored region.
