Bringing a clearer, more consistent HDR video experience to Chrome

We watch video everywhere these days, from the phone in our pocket to our laptops and smart TVs. And increasingly, we’re seeing stunning High Dynamic Range (HDR) videos right alongside Standard Dynamic Range (SDR) content, like when you’re scrolling through a webpage or social feed.

But if you’ve ever noticed an HDR video looking weirdly washed out, or its bright spots looking completely blown out and lacking detail, you aren’t alone. Because screens have vastly different brightness capabilities, mixing standard and HDR content on the same screen has been a massive challenge for the industry, and a frustrating experience for viewers.

To fix this, Google teamed up with Apple and NBCUniversal to create a brand new technical standard (officially named SMPTE ST 2094-50, being released by the Society for Motion Picture and Television Engineers). Ultimately, this standard ensures that no matter what device you’re using or what lighting you’re sitting in, the video you’re watching looks exactly the way the creator intended.

Here is a look at how we’re making HDR look its best on your screens.

Giving video the right "headroom"

Every display has a different maximum brightness. In the video world, the brightness available above a standard white background is called "headroom." When a video requires more headroom than your screen actually has, the brightest parts of the image get clipped or washed out. Furthermore, if you are sitting in a room where the sun is coming out from behind the clouds, your screen's ambient light sensor might change your display's brightness dynamically, throwing everything off again.

ST 2094-50 introduces two clever pieces of metadata (essentially, an instruction manual for your display) to solve this:

• Establishing a baseline (The Reference White Anchor): This acts as a consistent anchor point for the screen. It maps the brightest parts of standard content to a specific baseline, reserving all the extra brightness power strictly for the HDR video. This means standard and HDR content can finally share the same screen without throwing each other’s lighting out of whack.
• Adapting on the fly (Headroom-Adaptive Gain Curves): We are giving content creators a way to attach bespoke instructions right into the video file. If your screen has limited headroom, the video tells the display exactly how to adapt—intelligently compressing shadows and mid-tones to preserve the bright highlights without losing detail.

Honoring the creator's vision

The best part about this framework is that it puts the power back in the hands of creators. By giving screens exact instructions on how to adapt to lower brightness or changing room lighting, we ensure that the creative intent behind a video is beautifully preserved for the viewer, everywhere they watch.

Look forward to it in Chrome

We’re excited to bring this upgraded HDR experience to the web. Support for the finalized SMPTE ST 2094-50 standard is coming in an upcoming release of Chrome. And for developers looking to bring this incredible visual consistency to their own apps, we’ll be sharing much more about this standard—and how to adopt it in Android—at the upcoming Google I/O.