Contains Dockerfiles to build a Node.js based image resize server which uses sharp/libvips to return a resized/cropped version of an image in the mapped filesystem.

Libvips is a fast image processing library with low memory needs. It has a much better throughput compared to GraphicsMagick.

Sharp wraps Libvips as a Node.js module.

• follow the instructions in directory "node-bash" to build a Docker image with Node.js and bash (added for development purpose on top of Alpine)
• now build the Docker image for the image resize server in directory "resizeserver"

Run the container with the commands/parameters listed in "resizeserver/dockerrun.sh". This mounts a local directory into the Docker container and starts the server on port 4400.

There are two types of URLs: one to resize and another one to crop the image. In the example below we use with=500px and height=400px and process the image filepath "subdir/DSC00191.JPG" within the image base directory.

• http://localhost:4400/resize/500/400/subdir/DSC01888.JPG
• http://localhost:4400/crop/500/400/subdir/DSC01888.JPG

The code is available under Apache 2.0 license.

Copyright by Mindoo GmbH

• Node.js server idea and sourcecode are inspired by this blog article
• Performance comparison between various resize libraries (e.g. GraphicsMagick and libvips): article link