git clone git@github.com:M4Gd/chromecast-backgrounds.git
cd chromecast-backgrounds/
npm install lodash q request nopt chalk fs
sudo node cli.js --download="/Library/Desktop Pictures/my-images" --size=2560 --width=2560 --height=1440
The images will be downloaded in "/Library/Desktop Pictures/my-images" directory.
To check backgrounds preview, please visit upstream repo