Black bars at the top and bottom widen the frame horizontally and give a cinematic feel.
When to use it
16:9 cinematic ads, or when you want to look like a movie scene inside 9:16.
Example videos
You're doing cinematic black bars WRONG — Explainer: See the difference between laying black bars over the picture and actually cropping to the ratio.Aspect Ratios in Film: How to Choose The Most Cinematic Aspect Ratio #aspectratio — Explainer: Compare the feel of film aspect ratios and the bars at the top and bottom.Create Cinematic Black Bars in Premiere Pro — Explainer: See how to add cinematic black bars in under 20 seconds.
In AI video, like this
Generate in the original aspect ratio and make the bars in editing with drawbox or crop+pad. Don't put important subjects in the area the bars will cover, and in 9:16 use the bar space for captions and a logo.
One-click prompt
Add cinematic 2.39:1 black bars to a 1920x1080 clip (138 pixels top and bottom): ffmpeg -i in.mp4 -vf "drawbox=y=0:w=iw:h=138:color=black:t=fill,drawbox=y=ih-138:w=iw:h=138:color=black:t=fill" -c:a copy out.mp4. Keep important subjects out of the bar area.