subtitle-overlay

Overlay SRT, VTT, or ASS subtitles onto video clips via FFmpeg.

Updated Jan 30, 2026
One-click install
npx skills add https://github.com/akrindev/trimer-clip --skill subtitle-overlay
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: subtitle-overlay
Source: https://github.com/akrindev/trimer-clip/tree/main/skills/subtitle-overlay
Command: npx skills add https://github.com/akrindev/trimer-clip --skill subtitle-overlay

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve?

Add burned-in subtitles to video clips, essential for short-form content.

Core Features & Use Cases

  • Burn captions into videos to improve accessibility and engagement on 9:16 formats (TikTok, Shorts, Reels).
  • Support SRT, VTT, and ASS subtitle formats with customizable font, size, color, and outlines.
  • Platform presets streamline styling for TikTok, YouTube Shorts, and Instagram Reels.

Quick Start

Run the add_subtitles.py script with a video and a subtitle file to generate a subtitled video.

Frequently Asked Questions about subtitle-overlay

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I burn subtitles into video clips for TikTok and Instagram Reels?▼

Burn subtitles into video clips by rendering SRT, VTT, or ASS files directly into the output frames. This process permanently embeds captions, ensuring they display correctly on short-form platforms like TikTok and Instagram Reels without requiring separate subtitle uploads.

Can I customize caption font, size, and position for 9:16 social videos?▼

You can configure burned-in caption font, size, color, outline, and position options. Platform presets are also available to streamline styling specifically for 9:16 vertical formats used on TikTok, YouTube Shorts, and Instagram Reels.

Does FFmpeg support rendering SRT and VTT subtitle files into video frames?▼

FFmpeg supports rendering SRT, VTT, and ASS subtitle files into video frames through a deterministic CLI script. This integration ensures reproducible results when overlaying captions across multiple short-form video clips.

What's the best way to automate adding captions for short-form video workflows?▼

Automate adding captions by running a CLI script that processes video and subtitle files to generate subtitled output. This script enforces configurable styling and platform presets, making it ideal for batch processing short-form social video workflows efficiently.

Why use burned-in subtitles instead of soft subtitles for social media videos?▼

Burned-in subtitles are rendered directly into the output video frames, guaranteeing viewer visibility regardless of the viewing platform's subtitle settings. This approach significantly improves accessibility and viewer engagement on mobile-first social media platforms.