New_2_DVR

Hey community I need your help, I recently backed up to dvd a .tdb file from my dvr that I can view with XQ Player. However I need to convert it to an .avi file but I can't find anything that will allow me to on the web. Looked all through XQ Player for an export option, however there is none. Changing the .tdb to .avi dosn't work to any avail. Anyone had this issue before or any suggestions would be great, thanks!