DD is Convert and copy a file, write disk headers, boot records, create a boot floppy. dd can make an exact clone of an (unmounted) disk, this will include all blank space so the output destination must be at least as large as the input.
GUI for diskdump (dd). Harddrive clone and imaging tool.
This is a open source Graphical User Interface for the Unix Command dd. You can easily select the Input- and Outputstream, so you can clone or image your Harddrive or Partition.
What is new in 0.8
-added Image compression
-added detection of compressed Images
View the full changelog
-fixed “not enough Space” error
-some other bug fixes
-added more Languages
-cleaned up the Code a bit
Install gdiskdump in ubuntu
First you need to download .deb package from here once you have deb package you can install by double clicking on it.