Last month, Getty Images revised their term of use and allow their images to be embedded on other websites for free. The embedded images are watermark free and comes with a little note below the image stating the image copyright holder (see below sample). By embedding the images, it allows Getty to track how the image is being use and shared and can generate data for future potential use.
To embed the image, search on getty images and then click on the embed icon to retrieve the code.
Where enabled, you may embed Getty Images Content on a website, blog or social media platform using the embedded viewer (the “Embedded Viewer”). Not all Getty Images Content will be available for embedded use, and availability may change without notice. Getty Images reserves the right in its sole discretion to remove Getty Images Content from the Embedded Viewer. Upon request, you agree to take prompt action to stop using the Embedded Viewer and/or Getty Images Content. You may only use embedded Getty Images Content for editorial purposes (meaning relating to events that are newsworthy or of public interest). Embedded Getty Images Content may not be used: (a) for any commercial purpose (for example, in advertising, promotions or merchandising) or to suggest endorsement or sponsorship; (b) in violation of any stated restriction; (c) in a defamatory, pornographic or otherwise unlawful manner; or (d) outside of the context of the Embedded Viewer.
Getty Images (or third parties acting on its behalf) may collect data related to use of the Embedded Viewer and embedded Getty Images Content, and reserves the right to place advertisements in the Embedded Viewer or otherwise monetize its use without any compensation to you.
See here for other resources on copyright images.