Do you want to use an image in your thesis or dissertation?
1) Most royalty-free images allow reuse as long as it is not for commercial purposes. Thus, if you do not plan to publish your dissertation or thesis with a publishing house, the use of royalty-free images can be an option. To learn how to find royalty-free images, consult the "Finding Images" section of this guide.
2) If you use an image created by yourself that was previously included in a scientific article or book published with a commercial publisher, you must usually ask permission from the publisher to reuse your own image. In most cases, the publisher holds the economic rights to any article or book it publishes.
3) Most major publishers allow, for a fee, the reuse of published images in scientific articles through an automated rights management system called RightLink®. To access the form to request reuse, click on the article reference included in a bibliographic database (such as ScienceDirect, Wiley Online Library, IEEE Xplore, etc.), then on the link called: "Get Rights and Content", "Request Permissions", the copyright symbol ©, etc. If such a link is not available, contact the publisher directly.
The first example comes from Wiley Online Library, and the second from IEEE Xplore:
4) You must obtain the permission in writing, keep it in a safe place, and make sure the permission is irrevocable.
5) Even though you have obtained permission to reuse an image, you should still cite your sources. Publishers usually specify which citation style to follow in their author’s guide.
Do you want to use an image in your article thesis or dissertation?
Given that your dissertation or thesis will include one or a series of articles submitted for publication or already published with a commercial publisher, consult the "Article or Book" section of this guide to learn how to use images in this situation.