Docker build of ImageMagick
Docker container with ImageMagick installed.
The original purpose of this image was to use ImageMagick's convert executable to save PDF to JPG images. It was tested for this purpose to ensure the fonts of the PDF were rendered correctly with Ghostscript (gs) which is installed along side ImageMagick.
If you want to read a file from the host system, you can use the -v flag of the Docker CLI to bind a volume for input and output. An example usage is below.
Download the image from docker hub:
$ docker pull elifesciences/imagemagick
Use local Dockerfile to build the image on your machine:
$ docker build -t your_image_name .
First, build or download the docker image.
The default entrypoint of the image is to the convert program (https://imagemagick.org/script/convert.php).
Example usage of converting a PDF to JPG, if the PDF file is located at /tmp/cover.pdf, if the image you are using is named elifesciences/imagemagick, the following will produce a fairly crisp, good quality JPG file with a width of 1,200 pixels:
$ docker run --rm -v "/tmp:/imgs" elifesciences/imagemagick -resize 1200 -density 200 -quality 90 "/imgs/cover.pdf" "/imgs/cover.jpg"
If completed successfully, you should have a JPG file at /tmp/cover.jpg on the host machine.
This is only one example of running convert. You may be able to convert from any input file to any output file format (although this was not tested yet). If you specify a different --entrypoint value to the docker CLI you can probably invoke other ImageMagick programs, which was also not tested.
The Jenkinsfile is linked to a build pipeline, and when that pipeline is run, it will push an updated image to Docker hub with the tag latest, will be listed at (https://hub.docker.com/r/elifesciences/imagemagick).