Wikipedia
Qflix is a proprietary technology developed and licensed by Sonic Solutions and Pioneer Corporation to add CSS copy protection/ DRM to recordable DVD-R media.
Qflix is an implementation of the DVD Forum's DVD-Download specification, including extensions to the optical drive command set defined by the Mt. Fuji group of the IT industry. Sonic hopes to establish Qflix as a standard for recordable CSS and charge royalties for its use.
Recordable CSS (also known as CSS Managed Recording) was first announced by Sonic Solutions at the end of 2005 and was enabled by the DVD CCA in an amendment late in 2007. By using recordable CSS, movies can be burned to DVD in encrypted form just as on regular mass-manufactured DVDs.
With the Qflix system, writing CSS to recordable DVD requires special DVD writers and special-made recordable DVD-R media. The first Qflix drive and special Qflix media became available end of 2008. Prices of drives and media are higher than standard DVD drives and media. Dual-layer Qflix discs (DVD-9s) became available in the second half of 2009.
Recordable CSS DVD media are not writable in standard DVD burners and will not be recognized as blank media. Using Qflix technology with DVD-RW, DVD+R, and DVD+RW is technically possible but has not been pursued by the companies involved. The Qflix media is able to be written with a DXE Protected Disc Recorder (PDR).
It has been proven possible to use standard DVD recordable media to record CSS with more advanced disc writer technology, such as the DXE PDR. This removes the redundant requirement for the use of expensive custom media and all of the related infrastructure and royalty costs.