PNG Maker is a mini-toolbox that makes it easy to produce print-ready Portable Network Graphics (PNG) files from your MATLAB figures. There are two functions: 'saveprintpng' produces figures suitable for inclusion in an IEEE conference or journal paper; 'savepptpng' produces figures suitable for PowerPoint presentations. The functions take care of image sizing, fonts, etc.
This function uses MATLAB's built-in capabilities. No additional toolboxes are needed.