various virtual disk image conversion with qemu-img.exe

win32 qemu-img.exe support qcow2, vmdk, vpc ...

qcow2: a copy-on-write format that can be used on Microsoft Windows.

vmdk: VMware disk image

vpc: Microsoft Virtual Hard Disk (.vhd) (Virtual PC, Virtual Server, Hyper-V Server)

AMI: Amazon Machine Image

vhd => vmdk
qemu-img.exe convert {old}.vhd -O vmdk {new}.vmdk

vmdk => AMI
http://thewebfellas.com/blog/2008/9/1/creating-an-new-ec2-ami-from-within-vmware-or-from-vmdk-files

So that we can use commercial virtulization technology at this moment, and still have a chance to migrate to the open source solution (kvm/qemu)