Hope Video

The Hope Video is an item featured in Danganronpa 3: The End of Hope's Peak Academy. It was created by Ryota Mitarai to brainwash the entire world into believing in Hope, consequently removing all despair that had been caused by the Despair Video that Ryota unwittingly created at the behest/blackmail of Junko Enoshima.

Description
The video consists of a series of bright symmetrical pattern, similar to what one would see in a kaleidoscope. When someone watches such video, their eyes shine a similarly bright color, forcefully making them believe in hope and erasing any trace of despair from their minds.

Whoever watches the Hope Video also falls under the creator's commands, as seen when Ryota showed such video to Aoi Asahina and the Future Foundation's rescue squad. Kyosuke Munakata likened the process to stripping away the target's humanity by effectively forcing them to feel only positive emotions.

The Hope Video's primary flaw is that its effects will wear off over time unless the viewer is exposed to the video for approximately thirty minutes.

Danganronpa 3: The End of Hope's Peak Academy
The Hope Video was created some time before the Final Killing Game, with only Ryota and Kazuo Tengan apparently aware of its existence. Shortly after receiving the direct antagonist to the Hope Video and its suicide-inducing counterpart from Chisa Yukizome, Kazuo began planning the Final Killing Game in order to give Ryota the final push to broadcast his video all around the world.

However, the aforementioned plan was stymied by the fact Ryota became a participant of the Final Killing Game when he wasn't supposed to be, with his NG Code forbidding him to use his talent at all. As such, he was unable to make use of the Hope Video for the entirety of the event until Juzo Sakakura switched off the bangles' power and ended the killing game.

As soon as this happened, Ryota resolved to broadcast his Hope Video around the world, all according to the now-deceased Kazuo's plan. After explaining the video's effects to Aoi and Makoto Naegi, he showed the video to Aoi when she tried to prevent him from leaving, instructing her to restrain Makoto.

While making his way towards the Future Foundation's broadcasting studio, Ryota encountered a group of Future Foundation soldiers who had broken into the underwater complex to search for survivors of the Final Killing Game. He brainwashed the leader of the squad with his Hope Video before instructing him to upload the video to the rest of his troops and ordering them to prevent anyone from following him to the broadcasting studio. With the help of the brainwashed military, Ryota reached the studio and began uploading the Hope Video worldwide, with 30 minutes before full completion.

The former Remnants of Despair, awakened from their comas thanks to Izuru Kamukura, swiftly defeated Future Foundation's task force and faced Ryota. After hearing their words, he realized his error and stopped the Hope Video's broadcast, moments before full completion. Nonetheless, the brief broadcast of his Hope Video was sufficient to erase all traces of despair in the world.

After rejoining his former classmates on the boat back to Jabberwock Island, Ryota threw his phone into the ocean, taking the Hope Video with it.

Trivia

 * A tweet by Kazutaka Kodaka reveals that the brainwashing Hope Video made by Ryota Mitarai uses an image of Princess Piggles in a kaleidoscope fashion.