Product : Oracle, Oracle VM/3.4, x86 Edition
Feature : Virtual Disk Format, Storage, Network and Storage
Content Owner:  Roman Macek
Summary
Raw Images (*.img files)
Details
If a disk is created from OVM Manager it is created by default as a QCOW image and if it is imported it is converted from the original format to QCOW Images. More info on: http://docs.oracle.com/cd/E64076_01/