| By: Rachel Shaw

“Why is my livestream blurry…?”

…Is Adaptive Bitrate the cause? And why a bit of blur actually improves your live streaming.

Today we are answering one of our most asked questions in 2020. As we all rely more and more on technology for our meetings and events… we have gained some incredible benefits. But along with that, we have also had to deal with many new challenges including audio and buffering issues to name just a few. Last week we reviewed the best headsets to provide superior audio quality on your virtual meetings and events. So, this week, we are talking about video quality. Why is a stream sometimes blurry with apparently no reason? Is it true a blurry feed could be a way for my computer to improve the live streaming? Really?? Well, actually, yes! Let’s welcome Adaptive Bitrate and talk more…

What Is Adaptive Bitrate? 

Adaptive Bitrate (or ABR) is a content streaming technology and a great technique to improve your live streaming quality. It allows you to play multiple types of video renditions in different resolutions and bitrates at once.

Now, we all know that the term ‘’adaptive’’ means to adapt. But what about bitrate? Well, that’s easy. The term is used to describe the speed of an internet connection. A fast internet connection will usually have a higher bitrate than a slower internet connection. To put it simply, it means the rate at which ‘bits of data’ travel to the user’s machine.

How Is Adaptive Bitrate Used?

So, now that we know what both terms mean, how is Adaptive Bitrate used? Video players are able to use a client-side bandwidth estimation to determine which is the best rendition to use, given the current available bandwidth, network conditions, and user’s device performance. Adaptive Bitrate is used on the pretence that reducing the visual quality to the viewer is more important than the user experiencing that dreaded ‘buffering’ circle. To sum up in a simplified way – The overall goal of ABR is to improve your live streaming and deliver videos in the most efficient way possible, whilst maintaining a high-quality picture.

However this seamless content quality switching is not supported by progressive video playback. Most people tend to confuse adaptive streaming with progressive streaming. To end the confusion here, we’re going to explain what progressive streaming is so you’re able to get the full picture.

What is Progressive Streaming?

Progressive streaming refers to one single video which is streamed through the internet. This type of file is mostly (but not only) found in MP4. You’re able to stretch, compress, or squash progressive videos in order to fit a wide range of different screen sizes, but the video file will always stay the same.

The Problems You Can Face With Progressive Streaming

As with anything, Progressive Streaming can also come with its own set of issues. In this case, there are two in particular.

  1. With Progressive Streaming, the stream gets affected when played on a device screen that has a higher or lower resolution. For example, a video of 720 x 480px will pixelate if you play it on a screen resolution of 1280 x 720px. This does NOT improve your live streaming quality.
  2. The second problem is the one we mentioned earlier, ‘the dreaded circle’, i.e. buffering. This one is what we have all encountered many times throughout our lifetime, and it’s one that seriously annoys us. It mostly happens when the user has a weak or unstable internet connection, and is the ultimate patience tester. When this happens, the live stream quality of the video is not downloaded at a rate quick enough, resulting in a halt in the video until more data is fetched for further streaming.

So, How Does Adaptive Bitrate Streaming Solve These Issues?

Adaptive bitrate can provide an all-around better viewing experience. ABR removes the live streaming quality issues by allowing the content provider to create videos for screens of any size. When this happens, video files are adjusted in their creation as per the corresponding screen resolution on every device. This ensures that videos played on targeted devices do not get pixelated, meaning that it improves your live stream.

Let’s be honest, we’re all happy to watch a few minutes of a blurry, lower quality video if our internet speed happens to slow down for one reason or another. However, we’re NOT happy when our show stops completely whilst in the midst of an epic battle or an emotional scene, and we have to sit and wait for the spinning icon until it decides to catch up due to the live stream quality.

The Rise of ABR

In the earlier days, RTMP (Real-Time Messaging Protocol) was everybody’s go-to method when it came to live stream quality. When people started sending linear streams using RTMP, it enabled lightning-fast video delivery. However, with that being said, it always encountered issues when it came to getting through firewalls. RTMP streams were encoded at a bitrate that was comfortably less than the bandwidth of target viewers. They were then delivered through a dedicated streaming server as a continuous stream of data.

As with most things, it progressed. The industry eventually shifted in favor of HTTP-based (Hypertext Transfer Protocol) technologies. Now, bear in mind, these were not technically ‘streams’. Rather, they were the progressive downloads sent via regular web servers. The delivery method chosen works by downloading the video as you watch it, and the content could be cached on local servers and encountered much less trouble when getting through firewalls. However, this method didn’t work when it came to the optimisation of screen size, connectivity, or when it came time to improve your live stream. 

Thus *enter* Adaptive Bitrate Streaming. Content distributors began to encode streams into many different bitrates and broke them into fragments. They would then be indexed in a manifest file, and delivered to the player. The result? Very little buffering, fast start time, and a good experience for both high and low-end connections. All meaning just one thing – adaptive bitrate streaming is on the rise (and sometimes, experiencing a bit of a blurry stream is actually for the greater good!).

Looking for more ways to improve your virtual experience? Check out more over on our blog or follow us on LinkedIn.

If you’re planning in-person, hybrid or virtual events… we’re your guys and can help with our end to end solutions so get in touch today.