In MySQLWorkbench you can export EER Diagram to PNG, SVG, PDF and PostScript formats by following Reverse Engineer wizard steps.

In Sequel Pro you can export Graphviz dot files. The result is a basic table-based ERD. You can use graphviz to export the diagram to svg.

Install Sequel Pro, run the app, connect to your MySQL server and open the database you’d like to diagram. Go to File > Export > Graphviz Dot file, and save the file somewhere convenient.

Install graphviz from homebrew via your terminal:

$ brew install graphviz

Generate an SVG file of your diagram:

$ dot -Tsvg your_database.dot > your_database.svg

To convert SVG file to PNG using ImageMagick

convert your_database.svg your_database.png

To convert SVG file to PNG using libsrvg

cat your_database.svg | rsvg-convert -o your_database.png