How To Optimize RTMP Streaming For Low Latency

Real-time media streaming is a process of transmitting video and audio content in a near-real-time manner. RTMP (Real Time Messaging Protocol) has become the most popular protocol for streaming real-time media over the internet. Since the latency of this protocol is very low and usually around 5 seconds, it’s popular in applications where low latency is important, such as live streaming and gaming.

RTMP streaming helps for better audience engagement since there is no significant delay, as can be calculated using this streaming calculator, between the broadcaster and the viewer. Also, this protocol offers the streamer more flexibility and quality control options.

So it’s important to optimize RTMP streaming for low latency to get the best results. This blog post will show you how to do that. Before diving into the topic, let’s see what RTMP streaming is and how latency impact streaming quality.

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What Is RTMP Streaming?

The acronym RTMP stands for Real-Time Messaging Protocol. It’s a real-time protocol designed for streaming audio, video, and data over the internet. RTMP was initially developed by Macromedia (now Adobe) and is widely used by many popular streaming platforms such as YouTube, Facebook, and Twitch.

Streaming software like Castr offers RTMP server and client functionality that you can use to stream live video content to a global audience with ultra-low latency.

What Is Latency, & Why Does It Matter?

Latency is the most common term in the streaming industry. It’s the delay time between the moment something is captured by the camera and when it’s displayed on the screen. The lower the latency, the less time the viewer waits to see the content.

Latency is measured in seconds or milliseconds. Any latency over 5 seconds for live streaming is too high and will cause choppy video, out-of-sync audio, and buffer issues.

That’s why optimizing RTMP for ultra-low latency video streaming is important to ensure a better streaming experience for your audience.

Why Should You Optimize RTMP Streaming For Low Latency?

There are many reasons why you should optimize RTMP streaming for low latency. The main reason is to improve the viewer’s experience. Low-latency streaming is important for live events, gaming, and other time-sensitive content where every second matters.

Other benefits of low-latency streaming include:

Reduced buffering: Low latency streams have less chance of buffering since the data is sent in real-time.
Improved engagement: Low latency stream helps to keep viewers engaged since they can see and interact with the content in near-real-time.
Reduced costs: Optimizing RTMP streaming for low latency can reduce the cost of streaming since you don’t need to use extra hardware or software to achieve it.

How To Optimize RTMP Streaming For Low Latency?

There are a few things that you can do to optimize RTMP streaming for low latency. Let’s take a look at each of them.

Use A CDN

A content delivery network (CDN) is a global network of servers that helps deliver content faster by caching it at multiple locations worldwide. A CDN is one of the best ways to reduce latency and improve streaming quality.

When a viewer requests a stream, the CDN will serve the content from the server that’s closest to them. This reduces the distance the data has to travel and hence decreases latency. Most streaming platforms and services, such as Castr, offer CDN capabilities that you can use to deliver low-latency streams to a global audience.

Use Lower Resolution And Bitrate

Another way to reduce latency is to use lower resolution and bitrate for your live stream. This will reduce the amount of data that needs to be transmitted in real-time, decreasing latency. Of course, this will also result in a lower-quality stream. So, it’s important to strike a balance between quality and latency.

You can experiment with different resolutions and bitrates to find the sweet spot for your live stream.

Use Hardware Encoders

If you’re using software to encode your live stream, that’s another potential source of latency. Software encoders are slower than hardware since they’re not designed for real-time encoding. So, if you want to reduce latency, it’s best to use a hardware encoder. Hardware encoders are purpose-built for live streaming and can encode video in real-time with very low latency.

Use An Optimized Playback Player

The playback player can also add latency to a live stream. If you’re using a generic playback player, it’s likely not optimized for low-latency streaming. You can use an optimized playback player designed for low-latency streaming to reduce latency further. These playback players are usually part of a streaming platform or service.

Use A WebSocket Connection

WebSocket is a computer communications protocol that provides full-duplex communication channels over a single TCP connection. It’s designed for real-time applications and is much faster than the traditional HTTP protocol.

Using a WebSocket connection can help reduce latency since it’s designed for real-time data transfer. Most live streaming platforms and services use WebSocket to deliver low-latency streams. You can use the WebSocket protocol to reduce latency further and deliver your viewers the best possible streaming experience.

Final Thoughts

Low-latency streaming is important for live events, gaming, and other time-sensitive content where every second matters. There are a few things that you can do to reduce latency and deliver a better streaming experience for your viewers.

A CDN, lower resolution and bitrate, hardware encoder, and an optimized playback player can all help reduce latency. You can also use the WebSocket protocol to reduce latency further.

Do you have any tips on reducing latency for live streaming? Let us know in the comments below.