What are the main differences between MPEG-DASH and CMAF for live video streaming?

1 What is adaptive streaming?

Adaptive streaming is a technique that adjusts the quality and bitrate of a video stream according to the network conditions and device capabilities of the viewer. This way, the stream can adapt to changing bandwidth and avoid buffering or interruptions. Adaptive streaming also allows the viewer to choose their preferred quality level from a range of options.

2 What is MPEG-DASH?

MPEG-DASH stands for Dynamic Adaptive Streaming over HTTP. It is an international standard developed by the Moving Picture Experts Group (MPEG) that defines a common format and protocol for adaptive streaming. MPEG-DASH works by splitting the video into segments of different quality levels, each with its own URL. The segments are stored on a server and delivered over HTTP to the client. The client can request the segments that best suit its current conditions, and switch between them seamlessly.

3 What is CMAF?

CMAF stands for Common Media Application Format. It is another international standard developed by MPEG that aims to simplify and unify the delivery of adaptive streaming across different devices and platforms. CMAF works by defining a common media container format and segment structure that can be used by different streaming protocols, such as MPEG-DASH, HLS, or Smooth Streaming. CMAF also supports encryption, subtitles, captions, and metadata.

5 What are the benefits of CMAF for live video streaming?

CMAF offers some advantages over MPEG-DASH for live video streaming, especially in terms of latency and compatibility. CMAF can reduce the end-to-end latency of a live stream from 30 seconds or more to less than 5 seconds, by using shorter segments and chunked transfer encoding. This means that the stream can be delivered to the viewer faster and more synchronously. CMAF can also increase the compatibility of a live stream with different devices and platforms, by using a single media format and segment structure that can be played by different streaming protocols. This means that the stream can reach a wider audience and reduce the complexity and cost of encoding and storage.

6 How to choose between MPEG-DASH and CMAF for live video streaming?

The choice between MPEG-DASH and CMAF for live video streaming depends on your goals, requirements, and resources. If you need low latency, high compatibility, and simple delivery, CMAF might be a better option. If you need more flexibility, customization, and control, MPEG-DASH might be a better option. You can also use both standards together, by creating a CMAF-compatible stream and packaging it into MPEG-DASH segments. This way, you can leverage the benefits of both standards and optimize your live video streaming experience.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?