Many companies use this software for editing photos.
I use this for our company work and this works perfectly for image editing process.
iBooks Author - iBooks Author, free from the Mac App store, allows you to create beautiful Multi-Touch textbooks โ and just about any other kind of book.
GIMP - GIMP is a multiplatform photo manipulation tool.
Atavist - Atavist provides a suite of publishing tools to tell stories and build websites.
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.
Mobipocket eBook Creator - Mobipocket eBook Creator is one of the easiest way to create a professional level of eBooks by simply providing some HTML and image files to your publication.
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.