To access these features you must turn on the Advanced Embed Code in your Publish options. Once turned on, you will see the options like this:
Adjustable player size
By default the Adjustable player size toggle switch is activated. This means that your video player will fill the "container" or "element" in which the embed code is placed. This means that if the container is 500 px wide, the video will fill the width of that and stay at a 16:9 aspect ration. If the display sizing changes, the video size will change.
This is enabled by default to ensure that your video is fully responsive. If you deactivate this and configure your sizing manually, your video will no longer be fully responsive.
If you deactivate this toggle some more options will appear.
From this point, you can select the aspect ratio you want and then adjust the player width. As you adjust the width, the height will change automatically to stay at the same aspect ratio:
If you click on the drop-down and you will see some popular pre-set options:
In this example, we need the player to be 800 px wide with a 16:9 aspect ratio. Once we enter 800 into the Width field, the Height field will adjust automatically (to 450) for 16:9 aspect ratio:
The Floating Video option will let you set the player to float in the sidebar of the page so the video is visible as the user scrolls down the page.
You can customize the width of the player and the position of the player here.
In this example, the player will shrink to 25% of the original embedded player size and stay on the right side of the page: