Aspect ratio is a generation decision, not a cosmetic crop
A source image and its generated video should not be forced into the same square box. Cropping can remove visual context, change subject placement, and make the motion preview appear different from the downloaded result.
A good creation interface preserves the selected format and uses letterboxing when the source does not match. That is more honest than filling the frame by cutting away part of the input or output.
Use 1:1 for compact, balanced compositions
Square video works well in grid feeds and for close compositions that do not need much horizontal or vertical travel. It is also the safest preview format when the final publishing destination is not known.
- Good for discovery feeds and profile-style previews.
- Keeps the subject central and reduces extreme camera travel.
- May crop tall source images unless the interface uses contain rather than cover.
Use 9:16 for mobile-first vertical video
Vertical video gives more room for a full-height composition and matches common short-form mobile players. It is usually the strongest option when the source is already portrait-oriented.
- Designed for phone screens and vertical social formats.
- Preserves more of a portrait source image.
- Needs careful subject placement because side-to-side space is limited.
Use 16:9 for landscape scenes and wider movement
Landscape video supports multiple subjects, environmental context, and horizontal camera movement. It can be a poor default for a portrait source because conversion may require background extension or visible side padding.
- Useful for desktop players and wider scene composition.
- Allows horizontal movement without immediately leaving frame.
- Check the source preview before generation to avoid aggressive reframing.
How FAPPULSE handles format changes
Each FAPPULSE template declares one target format. The creation modal applies that same 1:1, 9:16, or 16:9 frame to both the source image and output video so the comparison stays the same size. Uploaded media is contained inside the target frame instead of being silently cropped.
Questions
What readers ask next
Should the input image and AI video have the same aspect ratio?
Yes for the creation comparison. Showing the source and result in the same target ratio makes reframing visible and prevents one preview from appearing larger than the other.
Why does object-fit cover cause problems in an AI video popup?
Cover fills the container by cutting away media outside its bounds. That can hide parts of the real source or output, so creation previews should normally use contain when format accuracy matters.
See the interface