Video Annotation Tool

A browser-based tool to annotate your videos after recording with precise audio overlays. Generates exact FFmpeg commands to merge audio snippets into your video timeline.

Features

• 100% client-side HTML/JS – No backend, no installation, no dependencies

• Post-recording annotation – Add audio comments, corrections, or narration over existing tracks

• FFmpeg command generation – Outputs ready-to-use merge commands

• Batch import – Auto-place audio files by filename timestamp:

  • (hh_mm_ss)_name.mp3 (e.g., (01_15_30)_correction.mp3)
  • (mm_ss)_name.mp3 (e.g., (05_45)_note.mp3)

• Qwen3-TTS integration – [Optional] Generate custom voice snippets via QwenTTS API

• SRT parser – Upload subtitle files to auto-generate annotation timestamps (Subtitles can be extracted from onscreen text via: https://github.com/timminator/VideOCR/releases/download/v1.5.1/VideOCR-GPU-v1.5.1-CUDA-12.9-setup-x64.exe )

Quick Start

Just open the HTML file

1. Download annotation-tool.html
2. Double-click to open in any modern browser
3. Start annotating – no server, no install.