GIMP Photo Image Crop Scale Export
The videos below walk you through how to edit photos using the free to use GNU Image Manipulation Program known as GIMPIn the training video we walk through how to crop, re-size or scale and image as well as how best to export and even convert an image to black and white. This will hopefully help you to understand enough for you to make a decision whether you have a go at doing this in house or to outsource it to a 3rd party like DT Innovation for your website optimisation.
This video walks through how to crop, resize, scale, make black and white and efficiently export an image using GIMP:
This video walks through how to crop a banner image using GIMP: