High-Quality Thumbnails with Chiitiler

Generate styled thumbnails from Portolan collections by rendering the actual styles/default.json server-side using chiitiler. This produces hero-quality images matching the browser portal — far better than the default matplotlib-based thumbnails.

When to use: For collections that need polished thumbnails (hero images, featured collections). This is opt-in and requires Node.js — the default portolan check --fix thumbnails remain the baseline.

Requirements:

• Node.js 18+ and npm
• Git (to clone chiitiler)
• A collection with .pmtiles and styles/default.json

Quick Start

Run this script in the catalog directory. It renders thumbnails for all collections that have PMTiles and styles.