How to Stamp a Transparent PNG Logo Across a Batch of Photos in Swift

These tutorials show how to work with transparent graphics and convert documents using Swift, Python, and PyMuPDF. The first article demonstrates batch‑watermarking photos with a PNG logo, scaling it to each image’s shorter side. The second explains turning a signature photo into a transparent PDF stamp, fixing lighting and background issues. The third details converting PDFs to Word by parsing glyphs and rebuilding layout with python‑docx. Each example provides reusable code snippets for developers.