Low resolution warning in Edocbuilder

This feature has always been confusing. I believe there is a calculation created to determine if an uploaded image is not good enough quality. I have changed all of my Edocs templates to the lowest resolution possible because even if their images are good enough quality they are still getting a LOW resolution warning. Alot of people add images direct from their phone that are 72dpi but they are over 100cm wide so the images are usually good enough.