Blur pad, crop, or letterbox?

Three answers to the same geometry problem

You have a 16:9 picture and a 9:16 hole. Crop fills the hole and throws away the sides. Pad (letterbox, pillarbox — here, bands above and below) keeps the whole 16:9 picture and fills the leftover with something else. Blur pad fills those bands with a blurred, usually darkened copy of the same frame. Brand-color pad fills them with a flat swatch. All three are valid. Shipping the wrong one is how a webinar becomes a cropped forehead, or a dance clip becomes a postage stamp.

Crop when the subject already wants to be tall

Talking heads that were framed centre, product hero shots, sports replays of a single athlete, and anything shot 9:16 in the first place should crop. Use the 16:9 to 9:16 cropper and pan until the face is in the safe rectangle, not merely in the frame. Crop is the wrong choice for two-shots, slides, and wides.

Blur pad when the 16:9 composition is the point

Interviews, panels, screen recordings, and landscape B-roll usually pad. A blur pad is the feed-native version: it looks like more picture, not like a graphic. Darken the blur so type you put in the bands (if any) still reads, and so the overlay chrome has contrast. The vertical video padding tool runs that kernel in the browser.

A flat brand-color pad is better when the brand colour is part of the identity, or when a blur would smear a logo that sat in the 16:9 lower-third. Do not blur a slide deck; the smeared type in the pad looks like a compression error.

Letterbox is not a crime

Black bars are honest. They are also easy to swipe past in a colour-feed. If you letterbox, use brand colour or a still from the same world, not default black, unless black is the brand. And still check the overlay: chrome will sit on the pad, which is fine, as long as it does not sit on the picture you cared about.