Although every case is unique, there are basic intellectual property use rules for academic images users in the US.
LifeHacker Chart, http://lifehacker.com/follow-this-chart-to-know-if-you-can-use-an-image-from-1615584870
Fair Use - Most academic use of images fall under the “fair use” clause. Basically, fair use allows academics to use copyrighted materials a single time to a limited audience without securing the permission of the copyright holder. Fair use is one of the most frequently contested copyright instances. Use the resources below to determine if your use counts as fair use.
Use this flowchart to determine if your use is Fair Use
More resources
Tip: Keep in mind, if your image is out of copyright already, you do not need to worry about fair use.
Image copyright is particular to each country. You’re bound to the copyright of the country where the image was made or where the copyright holder resides.
In the US, image copyright falls under Title 17 (1909) variously revised 1973, 2011 and most recently 2014, known as the STELA Reauthorization Act of 2014 (P.L. 113-200).
The Digital Millennium Copyright Act (1998) revised the law for electronic images. However, most accepted practice is based on legal precedent, not law. So, rather than citing law, copyright decisions are frequently determined by an important legal case.
Keep in mind that many institutions and individuals claim copyright on material they don’t have rights to or which is out of copyright altogether. For example, see the Highsmith case. Be sure to check, if you are using an image that is not covered by fair use.