Converting .VHD imag to RAW format

The correct format is:

qemu-img convert -f vpc -O raw lamp-3-x86.vhd lamp.raw

From the manpages of qemu-img:

qemu-img convert -f vpc -O raw lamp-3-x86.vhd lamp.raw
vpc – VirtualPC compatible image format (VHD).

Why must it be graphical?

qemu-img convert -f vpc -O raw something.vhd something.raw

(Edit: Fixed -f vhd to -f vpc.)