The first and second video assets 502 and 512 can be provided by a creative entity with creative control over the video assets. The creative entity can author (e.g., produce and edit) the first video asset 502 such that it is creatively suited for presentation in the first orientation (e.g., landscape orientation); for example, the creative entity can select camera shots, control scene placement, and position graphical elements such that the video content is understandable and engaging in a landscape orientation. The creative entity can similarly author the second video asset 512 such that it is creatively suited for presentation in the second orientation (e.g., portrait orientation). Viewability differences between the first orientation and the second orientation may result in significantly different creative demands of the first video asset 502 and the second video asset 512. For example, a full-body camera shot of a standing actor may be well suited for a portrait orientation, because the proportions of an actor standing upright may resemble the proportions of a portrait display. But the same full-body shot may be inappropriate for a landscape display, whose proportions vary significantly from those of the actor. Conversely, a wide-angle camera shot of a basketball court may present well on a landscape display, but may be entirely unsuited for a portrait display. Such differences may be especially pronounced on mobile devices, which may have small screens that make it difficult for a viewer to resolve small visual details (such as facial features). Accordingly, the creative entity may elect to produce a first video asset 502 that differs (even significantly) from the second video asset 512, even though the two video assets may relate to the same general content. For example, the first and second video assets may comprise entire separate camera shots and sequences, transitions, focal points, post-processing effects, overlays, or other video elements, as appropriate. Providing separate first and second video assets, where those assets may differ creatively, offers an advantage over processes in which a single video asset is manipulated (e.g., via cropping or letterboxing) for presentation at multiple different aspect ratios. The creative entity can make human authorship decisions based on what the entity decides would look best when presented at a particular aspect ratio.