Sometimes you may use an image purely as an illustration, e.g.
Such illustrations do not include information important to the point you are making and need not be included as full citations on your Works Cited or References page.
When considering whether to include brief citations on your visual aid, remember the general principle of giving credit to others for their work but also consult your professor for his or her preferences.
Keep in mind that if you were giving other types of speeches, e.g.
the rules may be different than for a college speech class. In those cases, consider professional standards in your field.
If you do include citations on your visual aid, follow the guidelines previously given for graphs, charts, audio and video files.
Source: NASA. "Free Floating (1984)."