Stock footage

File:FortressJap.jpg

This filename is kinda racist.

Stock footage refers to a sequence in film or television that can be frequently re-used. It is commonly used in animation to save the time and expense of having to re-draw sequences that are more or less assured to take place in every single episode.

In the context of Transformers, it applies to most of the series based off Japanese anime: The Headmasters, Masterforce, Victory, Beast Wars II, Beast Wars Neo, Robots in Disguise, and the Unicron Trilogy shows. All of those series would almost ritualistically showcase the same clips of characters transforming, combining, or deploying unique weapons. These sequences often seemingly transport the characters to a setting different from the actual events of that part of the episode, as the entire standard background fades away and is replaced by streaking speedlines and flashes of color, so they can be used no matter where the characters actually are in the script.

Blue streaks!

Stock footage sequences typically have more detail, higher frame rates, and more exaggerated posturing movements than the standard storytelling animation surrounding them. Supposedly, this is the method in which Japanese marketing has decided a toy's gimmicks are best "highlighted" in these advertoons.

The dub for Transformers Cybertron often poked fun at the practice, having characters narrate their filler stock-footage in ways that implied boredom or curiosity ("Why do we always go this way?"), or simply filled excessively-long sequences with snappy patter among the characters involved.

This practice is different from the stock animations used in the CGI-animated Beast Wars show, which often used "standard" sets of model movements for the characters' transformations from beast to robot mode to save the animators' time. However, these animations were not stock footage; each sequence had to be rendered out normally as any other each time they occurred, using different camera angles with the characters in the same scenery as they were before and after they transformed.

From Teletraan I: The Transformers Wiki, a Wikia wiki.