How to build mozjpeg on macOS (with PNG support)

Screenshot of library using

If you have installed mozjpeg library as a package via brew — you may see message about unsupported format by trying to compress .PNG (and even JPG) pictures.

You should to build this library manually, and if you are using macOS — lets follow these steps:

$ cd ~/
$ wget https://codeload.github.com/mozilla/mozjpeg/zip/master -O mozjpeg-master.zip
$ unzip mozjpeg-master.zip

1. Building

$ cd ~/mozjpeg-master
$ mkdir build && cd build
$ sudo cmake -G"Unix Makefiles" -DPNG_SUPPORTED=ON ../

2. Make links

You should make it for use mozjpeg command in command line
!!!Here is important to use /usr/local instead of just/usr/bin in macOS

sudo ln -s /opt/mozjpeg/bin/cjpeg /usr/local/bin/mozjpeg
sudo ln -s /opt/mozjpeg/bin/jpegtran /usr/bin/mozjpegtran

Using

Compress (lossy)

$ mozjpeg -quality 70 bla.png > new_bla.png

Optimize (lossless)

$ mozjpegtran -optimize -progressive new_bla.png > super_new_bla.png

Try to use these both commands to get most better result!