---
url: https://superduperai.co/library/captions/
title: Captions & text
entries: 8
---

# Captions & text

On-screen text, subtitles, reading speed, safe zones, and caption prompts.

- [Burned subtitles for 9:16: position, lines, characters, colour, as parameters](https://superduperai.co/library/burned-subtitles-9-16-parameters.md): 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.
- [Accessible on-screen text: contrast, the bottom 20 percent, no flashing](https://superduperai.co/library/caption-accessibility-checklist.md): A checklist for text that everyone can read, including people watching muted, on a small screen, in sunlight, or with photosensitivity. Eight checks, each with the parameter to test against.
- [Three caption variants plus hashtags, with per-platform length limits](https://superduperai.co/library/caption-variants-hashtags-per-platform-prompt.md): An agent prompt that writes three captions (short, story, question) and a hashtag set per platform, counting characters and hashtags against limits you paste in from today's upload form.
- [Burn subtitles with ffmpeg: the command with size, outline and margin](https://superduperai.co/library/ffmpeg-burn-in-subtitles-command.md): One ffmpeg command that burns an SRT into a 9:16 video with white text, a dark outline and the block held above the platform UI, plus the check that your ffmpeg build can run it at all.
- [Hook text on screen: a plan for the first three seconds, word by word](https://superduperai.co/library/hook-text-on-screen-plan-prompt.md): A prompt that plans what text appears in the first 3 seconds of a vertical video: the words, the moment each appears, the hold, what the picture does under it. Written so the hook works muted.
- [Reading speed for on-screen text and speech: the parameters to check against](https://superduperai.co/library/reading-speed-on-screen-text-parameters.md): How long a text overlay must stay up and how many words a voice can carry per second, given as parameters you measure on yourself, with the formula and the two failure modes: unreadable, and slow.
- [SRT cleanup: fix names from a glossary, merge short cues, cap line length](https://superduperai.co/library/srt-cleanup-glossary-merge-cues-prompt.md): An agent prompt that takes a raw speech-to-text SRT and returns one you can publish: names fixed from your glossary, sub-second cues merged, lines wrapped at a character cap, timings untouched.
- [Transcript to YouTube chapters: timestamps in the format the description needs](https://superduperai.co/library/transcript-to-youtube-chapters-prompt.md): A prompt that turns a timestamped transcript into a chapter list for the YouTube description: first chapter at 0:00, at least three, each 10 seconds or more, titles that say what the viewer gets.