HLS (HTTP Live Streaming) Adaptive Bitrate Streaming (Part 1)

For the past weeks, I have been involved in developing HLS system using AWS services. Before I present the full pledge of the project I have worked on, I thought it would be quite better to sum up the topic comprehensively.

HLS (HTTP Live Streaming) Adaptive Bitrate (ABR) streaming is a technique used to deliver video content efficiently over the internet by adjusting the quality of the video stream in real-time based on the viewer's network conditions. To put it simply, it is a technique for improving streaming over HTTP networks. It is what exactly the Video Streaming gaint, YouTube uses to play the video auto-playing into different quality.

Key Terms:

• Bitrate: The amount of data transmitted per second. Higher bitrates result in better quality but require more bandwidth.

• Segmentation: Dividing the video into smaller segments allows for more flexible streaming and easier adaptation to changing network conditions.

• Adaptive Algorithm: The algorithm used to determine the optimal bitrate based on network conditions and player performance.

How It Works In Brief:

Adaptive bitrate streaming works by dynamically adjusting the video quality based on the viewer's internet connection. First, the video is encoded into multiple versions, each with different bitrates and resolutions. These versions are then split into small segments, typically a few seconds long, allowing the video to be delivered in parts rather than as a whole file. When playback begins, the video player initially requests the lowest bitrate to ensure smooth streaming. At the end of each segment, the player assesses the network conditions and adjusts the bitrate accordingly. If the connection is strong, it switches to a higher-quality version; if the connection weakens, it shifts to a lower bitrate to avoid buffering. The player dynamically switches between different bitrate variants depending on the user’s bandwidth and device capabilities.

Benefits:

• Seamless Streaming: Reduces buffering and provides a smooth viewing experience even with changing network conditions.

• Device Optimization: Different devices (e.g., mobile, tablet, desktop) can be served video at resolutions optimized for their screens and performance capabilities.

• Efficient Bandwidth Usage: It ensures that users with lower bandwidth aren't overloaded with high-quality streams, saving data usage.

Use Cases:

• Video-On-Demand: Platforms like Netflix or YouTube utilize ABR to provide seamless viewing experiences across various devices.

• Live Streaming: Sports events, webinars, or other live broadcasts rely on HLS with ABR to ensure viewers get the best quality stream based on their current network.

Coming to an end, in future blogs I’ll be discussing the behind hood algorithm and talk about my system design for creating HLS adaptive bitrate streaming from scratch using AWS services.

Till Then, See You !!!

Keep Learning !!!