Thumbor

Thumbor is an open-source smart imaging service that dynamically generates derived images (thumbnails and transformations) from a source image. It runs as an HTTP server where transformations are defined through URL parameters, enabling consistent image handling across applications.

Key Features

• On-demand cropping, resizing, flipping, and transformation via URL-based HTTP requests
• Smart cropping using face/feature detection for improved focal-point selection
• Filter pipeline with chainable effects (for example brightness, contrast, grayscale, blur)
• Multiple loaders and storages to fetch and persist images (including file, HTTP, Redis, and MongoDB)
• Caching support to improve performance for repeated requests
• Extensible architecture for custom filters, loaders, storages, and processing engines
• Automatic delivery of WebP where supported to reduce bandwidth and improve page performance

Use Cases

• Centralized thumbnailing and responsive image generation for websites and mobile apps
• Optimizing and converting images (for example serving WebP) to reduce page load times
• Building an image transformation API decoupled from application code and storage backends

Thumbor is a practical choice when you need a dedicated, configurable image processing backend with smart cropping and a flexible plugin ecosystem. It helps teams avoid pre-generating many image sizes while keeping image delivery fast and consistent.