Delivery primer: landscape masters and portrait cut-downs
A landscape master is usually cut down to a portrait version for phone feeds. Cropping a 16:9 frame to 9:16 keeps about a third of its width and can lose a character in a two-shot. From 8 source pages, read 2026-09-25; no maker pays to be listed.
A landscape master is usually cut down to a portrait version for phone feeds. Cropping a 16:9 frame to 9:16 keeps about a third of its width and can lose a character in a two-shot.
Several vendors generate both shapes; one says each shape is generated fresh rather than cropped. Generating the portrait version separately costs a second generation and may not match shot for shot.
YouTube treats 16:9 as standard on a computer and adapts its player to other shapes.
1Reference first
The standard aspect ratio for YouTube on a computer is 16:9.
YouTube Help, recommended upload encoding settings
2Vendor figures that bear on it
with aspect ratios available for any platform.
Adobe Firefly, AI video generator page
Aspect ratio of the generated video. Valid values: adaptive (Default value)
Alibaba Cloud Model Studio, Wan3.0 video generation API reference
exports native 9:16 AI short drama when the episode lands.
DramaSo, home page and plans
- Video resolution and aspect ratio16:9 is the standard aspect ratio on a computer; the player adapts to other shapes
- Generator panel and FAQ16:9 and 9:16 in the generator's ratio control; the FAQ says ratios for any platform
- Wan3.0 video generationAdaptive by default; fixed shapes run from 21:9 cinema width through 16:9, 4:3 and square 1:1 to 3:4 and 9:16 portraitratio parameter
- ExportNative 9:16 vertical; no landscape shape is namedvertical short drama
- FAQ16:9 for widescreen or 9:16 for vertical, chosen before generatingposting to YouTube
- FAQProjects can be switched to vertical 9:16best dimensions
- Veo 3.1Landscape 16:9 by default, or portrait 9:16control the aspect ratio
- Aspect ratio tableSeven shapes, from the default 16:9 through 3:2, 4:3 and square 1:1 to 3:4, 2:3 and 9:16 portrait
3The production side of the spec
For a delivery question like “Landscape masters and portrait cut-downs”, SceneMixer states the following about what it produces:
Video is 16:9 landscape by default, with 9:16 vertical available; you set it once per project. Segments are typically 4 to 15 seconds, and some model tiers go to 30.
SceneMixer, AI Short Drama Generator — “What length and aspect ratio does it output?” (read 2026-10-13)
16:9 landscape (SceneMixer's default) and 9:16 vertical (the usual short-drama frame), chosen per project.
SceneMixer, Seedance 2.0 in a Real Short-Drama Pipeline — “Which aspect ratios does the pipeline generate?” (read 2026-10-13)
4Continue the primer
The primer reads printed figures; it does not measure any vendor's files.