How long does it take to double the speed in 60 minutes?

Divide the normal video time by the video playback speed to get the time needed to accelerate video playback, that is, 60 minutes divided by twice the speed equals 30 minutes.

Introduction to the film:

Movies, also known as moving pictures or dynamic pictures, that is, "reflection pictures", are works in the form of visual arts, which use moving images to express ideas, stories, cognition, emotions, values, or various atmospheric simulation experiences.

These images are usually accompanied by sound, and there are few other sensory stimuli. The word "film" is the abbreviation of cinematography, which is usually used to refer to film production and film industry, as well as the resulting art forms. Traditionally, movies are recorded on celluloid film through photochemical process, and then projected on a big screen through a movie projector.

Movable images of movies are used to create cameras that take moving pictures with actual scenes, using traditional drawing or micro-animation technology, with the help of CGI and computer animation, or through some or all of these technologies, and other visual effects.

Contemporary movies are usually completely digital in the whole process of production, distribution and screening, while movies recorded in photochemical form traditionally include similar optical sound tracks (graphic records of spoken language, music and other sounds, which are reserved for a part of the movie together with images, but not screened).