Movie enthusiasts hoping to legally make backup copies or space-shift or format-shift their legally purchased DVD or Blu-ray discs are out of luck. Agreeing with rights holders' and the Motion Picture Association of America's doomsday predictions, the Librarian of Congress on Tuesday rejected, again, another proposal that would allow users to finally rips these items for personal use.

Both forms of discs come complete with encryption protocols that cannot be circumvented for such personal uses, David Mao, the acting Librarian of Congress, ruled (PDF) in response to a request by Public Knowledge. Every three years, US copyright regulators entertain and rule on proposals for Digital Millennium Copyright exemptions.The DMCA prohibits circumventing encryption or access controls to copy or modify copyrighted works. Even if an exemption has been granted, it must be renewed in three years or it expires.

Because there is no encryption on CD music discs, however, owners of them are free to make backup copies or shift the tracks to a digital format under the concept of fair use. "These results continue to show the flaws in the law and the process of the DMCA. Even though the law clearly allows consumers to move their media between their personal devices, the Librarian of Congress and the Register of Copyrights allow the smallest mote of uncertainty to keep a common-sense activity illegal," said Sherwin Siy, the vice president for legal affairs at Public Knowledge in Washington, DC.

Regulators did grant DMCA exemptions to tinkering with the software on vehicles for research and modification purposes in addition to tinkering with the software on voting machines and medical devices.

Mao also (kinda) granted a highly confusing DMCA exemption for 3D printing devices to allow people to unlock them to enable the printing of material not approved by a printer's manufacturers.

The librarian did grant DMCA exemptions for copying "short portions" of DVDs or Blu-rays for "use in documentary filmmaking" and for "nonfiction multimedia e-books offering film analysis." Teachers and students may also crack the discs "for educational purposes" and for "film studies or other courses requiring close analysis of film and media excerpts."

Literary works distributed electronically may be cracked to enable read-aloud functionality for the disabled. Regulators also allowed unlocking and/or jailbreaking of mobile phones, "all-purpose" tablets, wearables, and smart TVs." A DMCA exemption to copying video games was also granted for limited purposes.