Images of all sorts--photographs, prints, paintings, illustrations, diagrams, graphs, maps, film, videos, digital or not--are protected by copyright just as other materials are.
First, determine if the image you want to use is in the public domain or available from a licensed resource.
The exemption for classroom use (Section 110) allows the limited display of images in the classroom or in the online teaching environment. See Media in the Classroom and TEACH Act.
For other uses of images, conduct a fair use analysis to see if your proposed use would require permission.
Complicating factors:
- You may be dealing with layersof images: e.g. a digital reproduction of a book illustration or photograph. Although the original may be in the public domain, the digital reproduction may still be covered by copyright or license.
- The fair use principles allow for the use of a portion of a work, but an image may be an entire work in itself. Note that illustrations in books and articles may be individually copyrighted separately from the book/article. The Fair Use Guidelines for Educational Multimedia recommend using no more than 5 works by the same artist/photographer or no more than 15 images or 10% from a collective work (whichever is less), but also have restrictions on where and for how long these works can be used. They also recommend using no more than "10% or 3 minutes, whichever is less, in the aggregate of a copyrighted motion media work."
- Copyright protects creative expression, so an image that displays more individual expression is more protected than a more generic depiction. A dramatic film is more protected than an instructional film or news broadcast.
- The purpose of your use is important. The use of images integral for teaching, comment, critique, or to illustrate a point would be more favored than a merely decorative or supplementary use.
