How to resize images from the console
We can resize our images from the command line using convert command from imagemagick. Install it if you dont have imagemagick:
sudo apt-get update
sudo apt-get install imagemagick -y
To resize an image with maximun width 800 pixels and maximun height 600 pixels but keeping the aspect ratio:
convert image.png -resize 800x600 resized.png
To get the resolution of an image:
identify -format "%wx%h" resized.png