Many companies use this software for editing photos.
I use this for our company work and this works perfectly for image editing process.
YACReader - Download YACReader for your platform. Windows, Linux, MacOSX. And enjoy you comic books cbr cbz with the best comic reader.
GIMP - GIMP is a multiplatform photo manipulation tool.
Tachiyomi - A free and open source manga reader for Android.
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.
Mcomix - MComix is an user-friendly, customizable image viewer.
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.