try the following. make an image for each color and make everything but that color transparent (none). Then combine the images.
Note your hex colors are way off with regard to the image you posted. The following is a unix IM command. For windows, change the \( to ( and the same for \) to ) and change the line ending \ to ^. Also change % to %%. See
http://www.imagemagick.org/Usage/windows/. Generally a good idea when you post to a topic to include your IM version and platform.
convert qp5vz7.png \
\( -clone 0 -channel rgba -fuzz 10% -fill none +opaque "#62921E" \) \
\( -clone 0 -channel rgba -fuzz 10% -fill none +opaque "#208C09" \) \
-delete 0 -compose plus -composite -compose over -background white -flatten qp5vz7_result.png
I assume the labeling of the hex colors inside the ellipse will be removed; otherwise you need to keep black as well and then distinguishing the labels from the black ellipse will require another solution.