pptx-image-compressor

A tiny CLI utility to compress images embedded in PowerPoint (.pptx/.pptm) files. It unpacks the PPTX, resizes and recompresses .jpg/.jpeg/.png images.

• Supports JPEG and PNG compression
• Resizes images to a maximum dimension while keeping an aspect ratio
• Adjustable quality/compression levels
• Creates a new compressed file, preserving the original
• Shows detailed compression statistics

Requirements

• Node.js 18+
• One of the following for ZIP operations:
  • macOS/Linux: unzip and zip installed (usually preinstalled on macOS and many Linux distros), OR
  • Windows: PowerShell 5+ (default on modern Windows) — the tool will use Expand-Archive/Compress-Archive automatically

Installation

npm install pptx-image-compressor -g

Usage

pptx-image-compressor <path_to_file.pptx> [max_size] [quality]

Parameters:

• path_to_file.pptx: Path to the PowerPoint file you want to compress
• max_size: Maximum width/height in pixels for images (default: 1920)
• quality:
  • JPEG: quality 1–100 (higher is better quality/larger size). Default: 80
  • PNG: inverse scale where 100 ≈ the lowest compression and 0 ≈ the highest compression; the tool maps this to PNG compression levels 0–9

Examples:

• Keep images up to 1920 px on the long side at default quality:

  node main.js "My Presentation.pptx"

• Resize to 1600 px and use JPEG quality 75 (and corresponding PNG compression):

  node main.js ".\slides\deck.pptx" 1600 75

On success, you’ll see a summary like:

✅ Done! File saved as: <original_name>_compressed.pptx

📊 Compression results:
   Original size: <X> MB
   New size:      <Y> MB
   Saved:         <Z> MB
   Compression ratio: <R>%

The tool creates a new file next to the original, suffixed with _compressed (e.g., deck_compressed.pptx). Your original file is left untouched.

License

MIT — see LICENSE.