Powerpoint-to-Nano

Convert a PowerPoint deck (.pptx) into a brand-new set of "Nano Banana" style slides using Google's Gemini image model, and export the result as a single multi-page PDF.

What this does (plain English)

• Step 1: Keynote opens your PowerPoint and exports every slide as a picture.
• Step 2: Each slide picture is sent to Gemini (image model), asking it to redesign the slide as a clean infographic.
• Step 3: All redesigned slide images are combined into one PDF.

Requirements

• macOS
• Keynote installed
• Python 3.10+ recommended
• Gemini API key
• google-genai SDK version that supports Interactions API (see requirements.txt)

Setup

python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
cp .env.example .env
# edit .env and add GEMINI_API_KEY

If you already installed dependencies earlier, upgrade to the required SDK version:

pip install -r requirements.txt --upgrade

First-run macOS permissions (important)

The first time you run this, macOS may prompt you to allow automation:

• “Terminal” (or your IDE) wants to control “Keynote”

Click Allow.

If it fails, check:

• System Settings -> Privacy & Security -> Automation

Usage

python pptx2nano.py /path/to/deck.pptx --workers 4

Optional style:

python pptx2nano.py /path/to/deck.pptx --style minimalist --workers 4

List built-in styles:

python pptx2nano.py --list-styles

Built-in styles (same names as the upstream repo)

• lego: Bright primary colors, blocky shapes, toy-like 3D appearance, snap-together aesthetic
• ghibli: Hand-drawn feel, soft watercolor palette, whimsical organic shapes, Studio Ghibli anime aesthetic
• cyberpunk: Neon colors, dark background, glowing elements, futuristic tech aesthetic, grid patterns
• minimalist: Clean white/gray palette, thin lines, lots of whitespace, simple sans-serif fonts
• blueprint: Technical drawing style, blue background, white lines, grid paper, architectural feel
• hand-drawn: Sketchy lines, imperfect shapes, notebook paper feel, casual doodle aesthetic

You can also use a custom style name like retro, corporate, vaporwave, etc.

Outputs

By default it writes to pptx2nano_output/:

• Rendered slide images (from Keynote)
  • pptx2nano_output/<deck_name>/rendered/*.png
• Generated slide images (from Gemini)
  • pptx2nano_output/<deck_name>/generated/slide_###.png
• Final PDF
  • pptx2nano_output/<deck_name>.pdf

Notes

• This tool keeps the original slide aspect ratio by using Keynote's rendering and by telling the model to keep the same aspect ratio.
• Parallel generation uses threads because the slow part is network calls to Gemini.