We’ve all experienced it. You’re streaming a movie or TV show on your favorite device, when—BAM—the picture quality gets hit with a sledgehammer. High-def becomes standard-def becomes no-def. Images linger on the screen long after they’re supposed to disappear, textures become grainy and pixelated, or even worse, the stream cuts out altogether.
It doesn’t seem to matter how solid your internet connection is or how cutting edge your device, the same problems persist. So just why is streaming quality so inconsistent? The answer is more complicated than you might think.
It all starts with a file
No matter what streaming service you’re using—Netflix, Hulu, Amazon, whatever—your experience begins with a video file. The streaming company offers up a video file on its servers, which the provider then transmits to you across the internet.
Quality of this source file can vary wildly. And as you can imagine, if the quality of the original video isn’t the best, your streaming experience is going to suffer. We’ll be diving into this issue deeper (and how THX is working to solve it) in future blogs, but for now just know that it’s the first thing that can negatively impact streaming quality.
The encoding conundrum
Streaming services have to deliver content on-demand and to a wide variety of devices, many of which feature radically different hardware and run diverse operating systems. It’s like trying to feed a family with a single course when everyone is asking for something different. And they’re all begging to be fed right now.
To get around this problem, streaming services use a technique called adaptive bitrate streaming (ABR). This process filters the file through an encoder, which then produces separate feeds of varying quality. There may be any number of streams produced, but for our purposes, it’s easiest to imagine three: a high quality stream, a medium quality stream, and a low quality stream.
Your OTT service decides which stream you get first, and then stream quality adjusts with the speed of your connection. If your device finds that your internet connection is strong enough to support a higher quality feed, it will move up to the medium quality encoding. And if your connection is top-notch, your device will request the high quality stream. Later, if your connectivity speed dwindles, your device will automatically “downshift” to the medium or low quality version of the file. This way, your streaming experience continues uninterrupted—in theory, anyway.
Racetracks vs. highways
Unfortunately, the internet is a very busy place. Your video stream has to navigate through exabytes of traffic. It’s also competing with other data that’s being delivered to your device simultaneously, like email or information from other websites and apps.
In this way, streaming is a vastly different process than getting content from a cable TV provider or through a Blu-ray player. These are fixed, controllable systems, where a video is delivered directly through a wire and into your TV without much to slow it down or impede its progress. Through these channels, ABR is unnecessary—the file can maintain its original, predictable quality from beginning to end.
Think of cable TV and Blu-rays like an empty racetrack, with the content being blasted to you in a straight shot. Streaming services operate over the internet, which is much more like a busy highway. The content has to move at varying speeds throughout all kinds of traffic to reach you, and there are infinitely more possibilities for delays, hazards, and jams.
The end result is a bit of a mess—a video that changes quality or stops entirely as your internet speed throttles up or down and other issues occur.
So what’s the solution?
Hopefully now you understand a little more about why streaming quality is inconsistent. Unfortunately, that won’t make it any less frustrating the next time your content doesn’t look as good as you want it to! We feel your pain, and that’s why THX is working hard to make streaming a better experience for everyone. Stay tuned for future blogs to find out how.