Download from Video Platforms

Download videos, audio, and captions from YouTube and 1000+ video platforms using yt-dlp.

Confirmation Required

IMPORTANT: Before executing any download, you MUST confirm with the user using AskUserQuestion:

•Show the URL to download
•Show the quality setting (audio/video)
•Show the output directory
•Ask for confirmation

Example confirmation:

code

Ready to download:
- URL: https://youtube.com/watch?v=xxx
- Type: Audio only / Video (1080p)
- Save to: Current directory

Confirm download?

Only proceed with the download command after user confirms.

When to Use

•Download YouTube videos/audio for offline use
•Extract captions from video platforms
•Get audio for local transcription or editing

When NOT to Use

•Just need transcription (use /omnicaptions:transcribe - Gemini handles URLs directly)
•Converting existing caption formats (use /omnicaptions:convert)

Setup

bash

pip install omni-captions-skills

CLI Usage

Note: By default, files are saved to the current working directory. Do not specify -o unless the user explicitly requests a different location.

bash

# Download audio only (default, saves to current directory)
omnicaptions download "https://www.youtube.com/watch?v=VIDEO_ID"

# Download video (1080p recommended)
omnicaptions download "https://youtube.com/watch?v=VIDEO_ID" -q 1080p

# Only use -o when user explicitly requests a different location
omnicaptions download "https://youtube.com/watch?v=VIDEO_ID" -o ./downloads/

Option	Description
`-o, --output`	Output directory (default: current)
`-q, --quality`	Quality: `audio` (default), `best`, `1080p`, `720p`, `480p`, `360p`
`-v, --verbose`	Verbose output

Quality Presets

Preset	Description
`audio`	Audio only (m4a/mp3), smallest size
`1080p`	1080p video + audio (recommended for video)
`720p`	720p video + audio
`480p`	480p video + audio
`360p`	360p video + audio
`best`	Best available quality (may be 4K+, very large)

Output

Downloads produce:

•Audio/Video file: .m4a, .mp4, etc.
•Captions (if available): .vtt or .srt
•Metadata: .meta.json (video resolution, title, etc. for ASS font scaling)

code

Video: ./VIDEO_ID.mp4
Audio: ./VIDEO_ID.m4a
Caption: ./VIDEO_ID.en.vtt
Metadata: ./VIDEO_ID.meta.json  # Used by convert for auto font size
Title: Video Title Here

The .meta.json file stores video resolution, which omnicaptions convert uses to auto-calculate font size for ASS karaoke output.

Supported Platforms

YouTube, Bilibili, Vimeo, Twitter/X, and 1000+ sites.

Related Skills

Skill	Use When
`/omnicaptions:transcribe`	Transcribe downloaded audio/video
`/omnicaptions:translate`	Translate captions with Gemini
`/omnicaptions:translate`	Translate captions with Claude (no API)
`/omnicaptions:convert`	Convert caption format

Workflow Examples

Important: Generate bilingual captions AFTER LaiCut alignment. Preserve language tag in filename.

bash

# Has caption: download → LaiCut align (JSON) → convert → translate
omnicaptions download "https://youtube.com/watch?v=xxx"
# → xxx.en.vtt
omnicaptions LaiCut xxx.mp4 xxx.en.vtt
# → xxx.en_LaiCut.json
omnicaptions convert xxx.en_LaiCut.json -o xxx.en_LaiCut.srt
# → xxx.en_LaiCut_Claude_zh.srt (after translate)

# No caption: download → transcribe → LaiCut align (JSON) → convert → translate
omnicaptions download "https://youtube.com/watch?v=xxx"
omnicaptions transcribe xxx.mp4
# → xxx_GeminiUnd.md
omnicaptions LaiCut xxx.mp4 xxx_GeminiUnd.md
# → xxx_GeminiUnd_LaiCut.json
omnicaptions convert xxx_GeminiUnd_LaiCut.json -o xxx_GeminiUnd_LaiCut.srt
# → xxx_GeminiUnd_LaiCut_Claude_zh.srt (after translate)