Google now officially supports SeekToAction markup for videos on your site, so that you can use the SeekToAction markup to communicate the key moments (timestamps) Google shows for videos in Google Search.

Google pre-announced this at Google I/O along with Clip markup but the Seek markup was not yet ready.

Google said this is “a new way for you to enable key moments for videos on your site, without the effort of manually labeling each segment. All you have to do is tell Google the URL pattern for skipping to a specific timestamp within your video. Google will then use AI to identify key moments in the video, and display links directly to those moments in Search results.”

Key moments looks like this:

Here are things you should keep in mind when implementing it:

Your URLs must have the ability to deep link into some point other than the start point in the video. For example, http://www.example.com/example?t=30 starts 30 seconds into a video.
Use SeekToAction markup on every video page where you’d like Google to automatically identify key moments, and follow our additional guidelines. Here’s a detailed example.
To automatically identify key moments in your video, Google must be able to fetch your video content files.
Note that SeekToAction markup applies only to videos embedded on your own site. If you post videos on third-party platforms where you don’t control the schema.org markup, you can reach out to those platforms to see if this markup is supported.

Here is the developer help docs on how to implement it and sample code:

Forum discussion at Twitter.