markdown-video

name	markdown-video
description	Convert Deckset-format markdown slides with speaker notes to presentation video with TTS narration. Use when user requests to create video from slides, generate presentation video, or convert slides to MP4 format.
allowed-tools	["Read","Write","Bash","Glob"]
license	MIT

Markdown Video Skill

Convert markdown slides to presentation video with AI-generated visuals and TTS audio narration.

When to Use This Skill

Activate this skill when the user:

• Asks to create video from markdown slides
• Requests to convert presentation to MP4 format
• Wants to generate narrated video from slides
• Needs automated slide-to-video conversion

Key Features

• Gemini AI-generated visuals: High-quality slide images with full emoji and Korean support
• OpenAI TTS narration: Natural voice from speaker notes
• Delta updates: Only regenerates changed slides (saves time and API costs)
• Multiple visual styles: technical-diagram, professional, vibrant-cartoon, watercolor

Input Requirements

• Markdown file with speaker notes marked with ^ prefix
• GEMINI_API_KEY environment variable for image generation
• OPENAI_API_KEY environment variable for TTS audio

Output Specifications

• MP4 video: 1920x1080 (Full HD)
• Duration: Each slide displays for duration of its audio narration
• File naming: {input_filename}.mp4

---

Workflow

Step 1: Generate Audio Files

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/generate_audio.py "{slides_filename}" --output-dir "audio"

Delta update: Only regenerates audio for slides with changed speaker notes.

• Use --force to regenerate all audio files

Output:

• audio/slide_0.mp3, slide_1.mp3, ... (0-indexed)
• Cache file: audio/.audio_cache.json

Step 2: Generate Slide Images with Gemini

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/create_slides_gemini.py "{slides_filename}" \
  --output-dir "slides-gemini" \
  --style "technical-diagram" \
  --auto-approve

Delta update: Only regenerates images for slides with changed content.

• Use --force to regenerate all slide images

Style Options:

Style	Description	Best For
technical-diagram	Clean lines, infographic icons, muted blue/gray	Technical, education
professional	Minimalist, geometric shapes	Corporate, formal
vibrant-cartoon	Bright gradients, flat design	Marketing, startups
watercolor	Soft pastels, organic shapes	Creative, personal

Other Parameters:

• --model: Gemini model (default: gemini-3-pro-image-preview)
• --aspect-ratio: 16:9 (default), 1:1, 9:16, 4:3, 3:4
• --start-from N: Resume from slide N
• --dry-run: Preview prompts without generating

Output:

• slides-gemini/1.jpeg, 2.jpeg, ... (1-indexed)
• Cache file: slides-gemini/.slides_cache.json

Step 3: Create Final Video

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/slides_to_video.py \
  --slides-dir "slides-gemini" \
  --audio-dir "audio" \
  --output "{output_filename}.mp4"

---

Delta Updates

Both audio and image generation support delta updates - only regenerating what changed.

How It Works

1. Content hashing: Each slide's content is hashed (MD5)
2. Cache storage: Hashes stored in .audio_cache.json / .slides_cache.json
3. Change detection: On subsequent runs, only changed slides are regenerated
4. File verification: Also checks if output file exists

Example Output

✅ Found 20 slides
   20 slides with speaker notes

✨ Delta update: 17 slides unchanged, 3 to regenerate

🎵 Generating 3 audio files...
Progress |████████████████████████████████████████| 3/3 (100.0%)

✅ Audio generation complete!
   Generated: 3/3 files
   Unchanged: 17 files (skipped)

Force Regeneration

To ignore cache and regenerate everything:

# Force regenerate all audio
python generate_audio.py "slides.md" --output-dir "audio" --force

# Force regenerate all images
python create_slides_gemini.py "slides.md" --output-dir "slides-gemini" --force

---

Quick Reference

Full Workflow (First Run)

cd "{slides_directory}"

# Step 1: Generate audio
python /Users/lifidea/.claude/skills/markdown-video/generate_audio.py "slides.md" --output-dir "audio"

# Step 2: Generate slide images
python /Users/lifidea/.claude/skills/markdown-video/create_slides_gemini.py "slides.md" \
  --output-dir "slides-gemini" \
  --style "technical-diagram" \
  --auto-approve

# Step 3: Create video
python /Users/lifidea/.claude/skills/markdown-video/slides_to_video.py \
  --slides-dir "slides-gemini" \
  --audio-dir "audio" \
  --output "presentation.mp4"

Update Workflow (After Changes)

Same commands - delta updates are automatic:

# Only regenerates changed slides
python generate_audio.py "slides.md" --output-dir "audio"
python create_slides_gemini.py "slides.md" --output-dir "slides-gemini" --auto-approve
python slides_to_video.py --slides-dir "slides-gemini" --audio-dir "audio" --output "presentation.mp4"

---

Requirements

System Dependencies

• Python 3.7+
• ffmpeg: brew install ffmpeg

Python Packages

pip install Pillow requests google-genai

Environment Variables

export OPENAI_API_KEY="sk-..."
export GEMINI_API_KEY="..."

---

Cost Estimation

Component	Cost	Example (20 slides)
Gemini images	~$0.04/slide	~$0.80
OpenAI TTS	~$0.015/1K chars	~$0.50
Total		~$1.30

With delta updates, subsequent runs only cost for changed slides.

---

Error Handling

No speaker notes found

• Slides need ^ prefixed speaker notes for narration
• Example: ^ This is the speaker note for this slide.

Pronunciation problems

• Replace technical terms with phonetic equivalents in speaker notes
• Test with --dry-run first

API errors

• Check API key environment variables
• Gemini rate limits: script includes 1-second delay between generations

---

Quality Checklist

Before marking complete:

• OpenAI and Gemini API keys configured
• Markdown file has speaker notes with ^ prefix
• Audio files generated successfully
• Slide images generated successfully
• Video plays correctly with synced audio
• Resolution is 1920x1080

---

Image Generation Mode

Two approaches for generating visuals:

Mode	Script	Best For
Slide-by-Slide	create_slides_gemini.py	Standard presentations, precise control
Section-based	generate_section_images.py	Long presentations, infographic style

When to Use Section-Based

• Presentations with 20+ slides
• Content naturally groups into logical sections
• Prefer infographic overview per section vs. individual slides
• Want to reduce API costs (fewer images)

---

Section-Based Workflow (Alternative)

For presentations with many slides, generate one infographic image per section instead of per slide.

Comparison

Aspect	Slide-by-Slide	Section-Based
Images	1 per slide	1 per section
Audio	Per slide	Per slide → merged by section
Review	Direct in markdown	Video script document
Best for	Short presentations	Long presentations (20+ slides)

Step 1: Generate Audio Files

Same as standard workflow:

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/generate_audio.py "{slides_filename}" --output-dir "audio"

Step 2: Generate Section Infographic Images

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/generate_section_images.py "{slides_filename}" \
  --output-dir "slides-section" \
  --style "infographic"

Style Options:

Style	Description
infographic	Clean professional with icons (default)
professional	Minimalist corporate design
vibrant	Bright gradients for marketing
technical	Flowcharts and technical diagrams

Other Parameters:

• --start-from N: Resume from section N
• --force: Regenerate all images
• --dry-run: Preview sections without generating
• --delay N: Seconds between API calls (default: 2.0)

Step 3: Create Video Script (Optional)

Generate a markdown document for reviewing narration:

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/create_video_script.py "{slides_filename}" \
  --output "video_script.md" \
  --image-dir "slides-section"

The script document shows:

• Section images embedded
• Speaker notes for each slide
• Easy editing format

Step 4: Review & Edit Narration

1. Open video_script.md
2. Review narration in blockquotes
3. Edit directly in the document
4. Update original markdown file with changes
5. Regenerate audio for changed slides:

   python generate_audio.py "slides.md" --output-dir "audio"
   

Step 5: Create Section-Based Video

cd "{slides_directory}"
python /Users/lifidea/.claude/skills/markdown-video/create_section_video.py \
  --slides "{slides_filename}" \
  --audio-dir "audio" \
  --image-dir "slides-section" \
  --output "presentation.mp4"

With config file (for custom section mappings):

python create_section_video.py \
  --config "sections.json" \
  --audio-dir "audio" \
  --image-dir "slides-section" \
  --output "presentation.mp4"

Config file format:

{
  "sections": [
    {"id": 0, "name": "title", "audio_slides": [0]},
    {"id": 1, "name": "introduction", "audio_slides": [1, 2, 3]},
    {"id": 2, "name": "main_content", "audio_slides": [4, 5, 6, 7]}
  ]
}

---

Section-Based Quick Reference

cd "{slides_directory}"

# Step 1: Generate audio
python /Users/lifidea/.claude/skills/markdown-video/generate_audio.py "slides.md" --output-dir "audio"

# Step 2: Generate section images
python /Users/lifidea/.claude/skills/markdown-video/generate_section_images.py "slides.md" \
  --output-dir "slides-section" \
  --style "infographic"

# Step 3 (optional): Create review document
python /Users/lifidea/.claude/skills/markdown-video/create_video_script.py "slides.md" \
  --output "video_script.md" \
  --image-dir "slides-section"

# Step 4: Create final video
python /Users/lifidea/.claude/skills/markdown-video/create_section_video.py \
  --slides "slides.md" \
  --audio-dir "audio" \
  --image-dir "slides-section" \
  --output "presentation.mp4"