Burned subtitles for 9:16: position, lines, characters, colour, as parameters
Settings for subtitles burned into vertical video for muted feeds: above the platform UI, two lines, about 32 characters each, white with a dark outline. Starting values, checked on a phone.
BURNED SUBTITLES 9:16, the parameters Position: bottom edge of the text block no lower than 20 percent up from the bottom of the frame (384 px on a 1920 px high frame); the platform's caption, buttons and progress bar live below that. Centre of the text block around 25-30 percent from the bottom. Never in the top 10 percent (status bar, account name). Lines: max 2. A third line hides the picture. Line length: about 32 characters per line including spaces; break at a phrase boundary, not mid-phrase. Size: a parameter; start at a font size around 4-5 percent of the frame height (80-96 px on a 1920 px frame in a 1080x1920 ASS script) and adjust on a phone. Colour: white text, black or near-black outline 2-3 px at 1080 width, no box unless the background is white; a soft shadow is optional. Timing: a cue is on screen 1-6 s, and its in point lands within 2 frames of the first word. Font: a heavy sans, the platform's native caption look; never a thin or serif face. Case: sentence case; all caps only for a one-word hit. Check: export 10 seconds, open it on the phone in the platform's own preview (not the gallery), muted, and look for text under the UI, a third line, a line that wraps on its own.
Paste into your assistant as the first message of a new chat; fill the braces first.
Steps
- Clean the SRT first (names, merged short cues, line length capped); burning does not fix a bad transcript, it makes it permanent.
- Burn with ffmpeg (see the burn-in command entry) or the editor's caption tool, using these parameters as the starting values.
- Watch the first 10 s in the platform preview on a phone. Adjust the vertical margin first, font size second, line length third. Save the numbers in the project; they are the same for the next video.
Tips
- Burned subtitles are for feeds with muted autoplay. On YouTube, upload an .srt track per language instead; a long video has a track picker and burned text cannot be turned off.
- The blurred-background 9:16 recipe in `/video-edit` centres the picture at 34 percent of the height for the same reason: the platform covers the bottom.
| works with | ffmpeg: A terminal command you run yourself. · CapCut / any editor: A manual recipe for any editor. · By hand: No tool needed: a checklist or a technique. |
| skill | npx skills add fortunto2/solo-factory/video-edit · source |
| cost | Free. No API, no key. |
| status | Unverified: written from the technique, not yet run end to end by us. |
| license | CC BY 4.0 for the text here; skills are MIT. |
| updated | 2026-11-01 |
| for agents | burned-subtitles-9-16-parameters.md |
Related
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