If you missed the previous post, essentially it means we are getting the option to not only select which resolution we want to watch a video in (including 2K and 4K), but the player will also adapt to the internet connection and screen size of the viewer. Here's more on that from Vimeo:

Adaptive streaming means that instead of loading the video as a single, large file, we load a bunch of much smaller files as the video plays. We can then choose from all the qualities available, factoring in your Internet connection speed and screen size, to make sure that playback is always the best it can be and is never interrupted.

We’ve already implemented adaptive streaming on iOS, Apple TV, and Xbox 360, and over the next few months, we’ll be updating the rest of our mobile and TV apps to use it. We’re still in the process of testing the performance of these features, but everyone will have access to them within the next few months or so.

It's important to note that Vimeo's 2K is not traditional DCI 2K, but is instead a 1440p mode like YouTube. Here are Vimeo's recommended compression guidelines so far:

• 2K (2560×1440): 20-30 Mbit/s
• 4K (3840×2160): 30-60 Mbit/s

Obviously there will be kinks to be worked out, especially as the adaptive streaming isn't being rolled out for everyone yet. Most videos will simply have the resolution selection option under the "HD" part of the play bar, and not the Auto option yet. Some users have complained about videos defaulting to 360p, though this really shouldn't be happening according to Vimeo, and as part of the adaptive streaming they will strive to give the highest quality within the constraints of the user's internet connection. At the moment according to Vimeo staff, for those who don't have adaptive streaming enabled yet, if a user selects something like 720p or 1080p, it should default to that for all videos they are watching on the site. Once adaptive streaming rolls out though, you'll get the highest quality possible based on where you're watching from and your connection.

4K and 2K For All

As for 4K, here's how that rollout is going to happen:

• PRO members: Any 2K or 4K video files you’ve uploaded since August 4, 2015, or anytime thereafter, will be streamable in 2K and 4K on compatible devices and connections.
• Plus members: Any 2K and 4K video files you’ve uploaded since yesterday, December 8, 2015, will also be transcoded and ready for ultra-HD viewing.
• Basic members: Hold tight: we’ll start transcoding your 2K and 4K uploads very soon!

They are currently showing off two examples that have both adaptive streaming and 4K:

Basic Member Accounts Get More

Free accounts will get access to HD embedding outside of just Vimeo.com:

In addition to adding 2K and 4K resolutions, for Plus and PRO members, we’re automatically making both 720p and 1080p versions of the videos you upload (no need to upgrade each individual video any longer), and we’ll do the same for Basic members starting next year. And to make sure that adaptive streaming works well for all, we’ve also removed the HD embedding restriction from Basic members’ videos — which means people can watch your HD videos outside of vimeo.com, too!

While this is taking away some of the features users were paying more for, it does mean that free accounts will be able to have their HD videos embedded anywhere. This is great especially for people who did have paid accounts in the past but have chosen to no longer pay — their videos will still show up in HD embedded on third party sites. 

60fps Has Arrived

While cinema has traditionally avoided 60fps (played back at 60fps), it's something that has been explored for sports and other extreme sports activities to avoid motion blur (and it's great for video games). Even some nature and other documentary-type shows have utilized the frame rate to give a crisper image. It may not work for all videos, but if you happen to be shooting in 1080p 60fps, Vimeo will now support it, just like YouTube has already done so far. 

For more on all of these features, check out the Vimeo post.

Source: Vimeo