The Ultimate Guide to Live Encoding
In today's competitive online video market—where quality of experience is table stakes—ensuring your team has the right encoder for your unique needs is key. Streaming data must be compressed for efficient delivery without sacrificing quality. While most encoders deliver on this requirement, they vary in terms of performance and feature set.
Posted on August 16, 2023
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Consumers expect quality video experiences at the touch of a button. Without live streaming encoders, though, this wouldn’t be possible.
Streaming encoders are an essential tool for transporting live video across the internet. Their utility is twofold: Content distributors use encoders to digitize video (changing from analog to digital), while simultaneously shrinking gigabytes of data down to megabytes.
In today’s competitive online video market—where quality of experience is table stakes—ensuring your team has the right encoder for your unique needs is key. Streaming data must be compressed for efficient delivery without sacrificing quality. While most encoders deliver on this requirement, they vary in terms of performance and feature set.
What Is a Live Streaming Encoder?
A live streaming encoder is a solution used to convert RAW video data and compress it for distribution across the internet. Sometimes encoders are built into the camera, as with IP surveillance systems. But more often, broadcasters rely on software and hardware live streaming encoders to get the job done.
Milliseconds after a stream is captured, an encoder uses video compression algorithms called codecs to condense the data. Live encoders employ lossy compression, tossing out unnecessary data to ensure the greatest reduction in file size possible without degrading perceptual video quality.
The encoder then packages the stream for delivery across the internet. This involves putting the components of the stream into a commonly accepted contribution format such as Real-Time Messaging Protocol (RTMP) or Secure Reliable Transport (SRT). RTMP and SRT describe streaming protocols that transport content between the encoder and the online video host.
In most cases, these streams are repackaged at the next step of the workflow for delivery to the end user. Protocols like HTTP Live Streaming (HLS) and Dynamic Adaptive Streaming over HTTP (DASH) come into play here. These protocols make the content more scalable and adaptable for delivery to viewers with varying internet speeds.
Once the stream reaches viewers, a video decoder built into the player software or set-top box will decompress the data for playback. At this point, the video content has often been encoded, transcoded, delivered globally, and decompressed. Thanks to the efficiency afforded by the encoding solution used, viewers are none the wiser. All they know is that the video content is streaming live and in high quality.
Transcoding vs. Encoding: What’s the Difference?
The terms transcoding and encoding are often used interchangeably. We’ve even been known to combine the two here at Bitmovin. For the sake of clarity, let’s define each term:
What Is Encoding?
Encoding describes the process of converting RAW video into a compressed digital format directly after the video source is captured. Video encoding always occurs early in the streaming workflow. It’s also a must for every broadcast scenario because video content can’t be transmitted across the internet without being shrunk into a more manageable size.
Sometimes the encoder is built into the capture device itself. Other times, it requires a secondary software or hardware encoder for live streaming. With contribution encoding, content distributors generally convert the stream for delivery via RTMP, RTSP, SRT, or another ingest protocol.
What Is Transcoding?
Transcoding involves taking an encoded stream, decompressing and altering the content in some way, and then compressing it for delivery to end users. Transcoding isn’t always required, but when it is, it occurs after the video source has been encoded.
Transcoding can be done using a live video streaming solution like Bitmovin, a live stream platform like Facebook Live that has transcoding technology built into its infrastructure, or an on-premises streaming server. In common streaming workflows, RTMP-encoded streams are ingested by the transcoder and then repackaged for adaptive bitrate delivery via HLS and DASH. This ensures that the content reaches more users, plays back on more devices, and adapts to viewers’ connectivity constraints.
A Simple Analogy for Transcoding and Encoding
Let’s use the gasoline supply chain to better demonstrate the difference between these two live streaming processes.
- First, crude oil is extracted from underground reservoirs. This crude oil can be thought of as the RAW video source itself.
- Next, the crude oil is refined into gasoline for bulk transport via pipelines and barges. This is the encoding stage, where the video source is distilled to its essence for efficient transmission.
- Finally, the gasoline is blended with ethanol and distributed to multiple destinations via tanker trucks. This represents the transcoding step, where the content is altered and packaged for end-user delivery.
Why Do I Need a Live Streaming Encoder?
The ability to fit more data into less space has changed the way video is stored and distributed. What once required renting VHS tapes or purchasing DVDs can now be accomplished by simply streaming video content over the top (OTT) or storing it in the cloud. Video encoders make this possible by compressing streaming data into a manageable size.
No matter the industry or use case, encoding is a key step in the video delivery chain. Looking to build immersive online fitness experiences like ClassPass? You’ll need an encoder. Hoping to distribute breaking news online by swapping out expensive satellite trucks for a remote streaming setup? Your live encoder will play a vital role. Simulcasting to multiple online video platforms (OVPs) like YouTube and Facebook? Great! Here are instructions for connecting an encoder to each platform:
• Create a YouTube Live stream with an encoder
• Connect streaming software to Facebook Live
What About Simple Broadcasts That Don’t Require Additional Software or Hardware?
Encoding may seem like an unnecessary step given that anyone can go live using their smartphone. But it’s always taking place in the background. And even when you have the option to stream directly to a site without using an encoder, doing so sacrifices quality and control. That’s why most social media sites offer live encoding software integrations like Instagram Live Producer.
Above anything else, implementing one of the recommended encoders below paves the way for more professional live broadcasts. Most encoders allow you to manage complex productions by switching among cameras, microphones, and media assets. What’s more, advanced solutions allow you to add special effects and graphics for a more polished end-user experience.
Luckily, free software encoders and low-cost hardware encoders exist. That means there’s no need to break the bank when designing your live streaming setup. It’s up to you to decide whether you need all the bells and whistles or if free software encoding does the trick. Let’s look at some of the considerations that might sway you in either direction.
The 5 stages of live streaming delivery
How Important Is Low Latency?
How important is low latency? It depends on what you’re streaming. For standard live streams like online news, your viewers won’t likely notice a 10-second lag. On the other hand, if you’re building interactive video experiences for online gaming or ecommerce, even five seconds of latency could ruin the entire event.
In our 2022/2023 Video Developer Report, live low latency ranked as the second-biggest challenge that content distributors are experiencing with video technology. It’s also the area where survey participants see the most opportunity for innovation in their service. Despite this, 47% of those surveyed indicated that they weren’t using low-latency streaming technology.
What Gives?
Why would latency rank as a top concern when almost half of the developers participating in our report aren’t leveraging technologies designed to reduce video lag?
As it turns out, “low latency” is a relative term. For some, sub-five seconds is the ultimate goal. But for truly interactive video applications (like online betting, live auctions, and multi-player quizzes), playback delay often needs to be in the hundreds of milliseconds.
There’s also the issue of perceived need. In conversations with customers, we’ve found that video distributors fall into one of three camps:
- They absolutely need low-latency or real-time streaming to ensure that the viewer experience is high quality and competitive in their market.
- They think they need to decrease latency because there is so much buzz surrounding the topic, but in reality, reducing lag has minimal impact on how well the content is received.
- They’re well aware that quality and scalability are more important factors for their audience, and as a result, aren’t investing resources in driving down latency.
How Does Live Encoding Impact Latency?
For use cases where reducing latency is a must, there are multiple opportunities to decrease the broadcast delay across the video supply chain. The live encoder, packager, CDN, and player must all be optimized accordingly. Things that can impact the speed of video encoding include the encoder itself, which codec and protocols you use, and configurations like the bitrate and resolution.
Broadcasters committed to lightning-speed delivery should look for contribution encoders that support:
- Low-latency protocols like SRT and Zixi
- Ethernet connectivity
Additionally, you might have to compromise on quality by decreasing frame rate and resolution if low latency is essential.
When Would I Need a 4K Live Streaming Encoder?
4K streaming (and even 8K) comes into play on the other end of the spectrum. Content distributors prioritizing ultra-high-definition video will need an HD live streaming encoder capable of producing source streams with a resolution of 3840 x 2160 pixels. While sharper than 1080p, these high-bitrate streams are resource-intensive and costly to distribute. For that reason, you’ll want to be sure that 4K UHD is a business need and not a nice-to-have feature that lacks any real ROI.
Beyond your 4K live streaming encoder, you’ll also need a 4K camera or higher, a transcoding service capable of ingesting and egressing 4K video, and an HTML5 player (go2sm.com/4khtml5) that supports 4K playback. Your viewers will also need 4K playback devices to benefit from these efforts. Finally, both broadcasters and end-users will require high-speed internet for these types of streams.
Video Developer Report 2022/23: Which technology do you use for low-latency streaming?
But back to the question at hand: What types of broadcasts warrant 4K HD video? We can’t provide clear-cut criteria. In general, though, the following video streams are best suited for 4K encoding:
- High-production value content like live sports events
- Immersive experiences like virtual reality (VR) and gaming
- Cinematic content for over-the-top (OTT) distribution
Check out our 4K streaming customer spotlight on the Brazilian broadcaster Globo.
Software vs. Hardware Encoders: Which Is Right for Me?
Once upon a time, dedicated hardware was the only choice for live video encoding. Computers are now powerful enough to handle such a strenuous task—but just because you can use software doesn’t mean you should.
Hardware encoders have the dedicated power to encode high-quality streams quickly. Software encoders, on the other hand, must make concessions to encode in real time. As a result, you’ll sacrifice quality for efficiency—or vice versa—when going with a software encoder.
That’s not to say that software encoding isn’t a viable option for professional broadcasting. Live streaming software like OBS, Wirecast, and vMix, are cost-effective and easy to use. For that reason, we’d recommend starting with one of these solutions if you’re new to broadcasting. Audio, video, and graphics are often stored on a computer anyways, so software encoding can streamline the process. One caveat, though: Make sure your computer is up to the task if you’re going this route.
With hardware encoding, alternatively, you’re able to free up resources and support more advanced configurations. Hardware can get pricey, though.
11 Considerations When Choosing a Live Streaming Encoder
Aside from the considerations above (whether or not your workflow will include encoding and transcoding, software vs. hardware solutions, 4K resolution, and low-latency encoding), here are 11 factors to mull over before selecting a live streaming encoder.
1. Cost and/or ability to trial: Price point will always be the deciding factor. If your budget is nonexistent, that makes things easy: Go with a free software option like OBS. Alternatively, you might be able to gain internal buy-in on a pricier option by creating a proof of concept first. In those cases, Telestream’s Wirecast production studio software and the vMix live video production software both offer free trials to get started. Hardware will always be the most expensive avenue. Even so, software options have hidden costs because they must be
deployed on a reasonably powerful computer. If you don’t have an adequate computer to start, hardware encoding might be right for you. Anyone dead set on hardware but lacking in budget should go with a low-cost option like the Videon EdgeCaster.
2. Support for your ingest protocol(s): All encoders covered below support RTMP output. This is the de facto standard for first-mile contribution. Most media servers can receive RTMP and all major social media players like Facebook, YouTube, and Twitch accept it. That said, there’s a growing list of RTMP alternatives today. These include SRT, Zixi, QUIC, Reliable Internet Stream Transport (RIST, rist.tv), and Web Real-Time Communications (WebRTC). Often, these new technologies are open source and more advanced. SRT and RIST, for example, promise better resilience to network issues like packet loss while ensuring low-latency delivery over public networks. If these protocols play a role in your workflow, you’ll want to find an encoder that can output them. OBS and vMix both support SRT on the software front; Ephiphan’s Pearl Nano and Haivision’s Makito X are great SRT options in the hardware world.
3. Integration with existing equipment and capture devices: Today’s encoders range from specialized component tools to out-of-the-box studio production kits. While hardware encoders help integrate all of your equipment into a fully functioning studio, they might not be compatible with your current gear. Confirm that your encoder supports the input types (HDMI vs. SDI), resolution (1080p vs. 4K), and frame rate (30 vs. 60 fps) of your camera or video source.
4. Compatibility and/or integration with your destination: Is your encoder compatible with the platform to which you’re streaming? Whether the next step in your workflow is a transcoding solution, social media service, or something else entirely, you’ll want to ensure that it connects with your destination(s) prior to settling on a live streaming encoder. Some encoders even offer custom integrations with common video workflow tools. OBS, for instance, integrates with a variety of video sources and transcoding solutions. These include integrations with Zoom and Bitmovin’s Streams product. Similarly, the Matrox suite of hardware encoders integrates with Facebook Live and YouTube.
To rehash the last three considerations in this list: It’s vital that you look at your entire streaming ecosystem and make sure the encoder you’re leaning toward fits with your tech stack.
5. Internet connection: In a perfect world, all live stream encoding would utilize a wired Ethernet connection to high-speed internet. That’s not always the case, though. Remote encoding has become increasingly common, which is why many encoders today offer the flexibility to use Wi-Fi, Ethernet, or both. If neither Wi-Fi nor Ethernet is available at your production location, you’ll need an encoder like LiveU that can connect via mobile networks. Regardless, we always suggest testing your internet strength to verify the stability of your broadcast signal. High-speed internet is also crucial for producing 4K streams, so try to go with an Ethernet-connected encoder when UHD resolution is the goal.
6. Use case: The perfect encoder for your application will be ill-suited for another’s. That’s why the specifics of your scenario should help determine which encoder makes the most sense. Are you streaming a high-action football match that switches between multiple cameras or a talking-head commentary with a single video and audio source? Do you need to encode from remote locations or are you always broadcasting from the same studio? All of these specifics will dictate which option’s best.
7. Feature set: Encoders vary drastically in terms of the feature set. Some broadcasters require preset configurations for different productions, while others are vlogging from their desk with minimal requirements. There’s a lot to think about in terms of encoding features—including recording, compositing, audio mixing, lower-thirds graphics, subtitles, analytics, and monitoring.
8. Simulcasting: It’s also worth pondering whether you require multi-encoding functionality, simulcasting capabilities, or both. Anyone simultaneously streaming to multiple destinations should prioritize these capabilities or use a streaming solution like Bitmovin to build custom video experiences—including distribution to any device or social media platform.
9. Redundancy: Depending on the criticality of your streaming content, you might require encoder and/or output redundancy. This helps ensure that your stream is resilient enough to survive a cable failure, loss of internet connectivity, or hardware (computer or encoder) failure. For anyone hosting live shopping experiences or news streams, redundancy is an important consideration.
10. How much noise can you handle (hardware)? Powerful hardware encoders often come with noisy built-in fans. If your encoder is stored away in a closet, this won’t impact your decision. But if your entire studio setup is constrained to the same closed space from which your stream is being broadcast, you’ll want to find a hardware encoder that keeps the sound to a minimum.
11. Operating system (software): Streaming software like vMix works only with Windows 7 and later. Likewise, Wirecast isn’t available for Linux operating systems. Make sure to verify that your live software encoder is supported by your operating system before making a purchase. The best encoder software for live streaming is always going to be one that runs on your OS!
Conclusion
So, what’s the best live streaming encoder? It all depends on your needs. For big production content and complex studio setups, a hardware encoder or even hybrid hardware + software solution is often the best route.
BITMOVIN is the Emmy award-winning category leader in video streaming infrastructure. The company has been at the forefront of industry innovation and all major developments in the online video streaming industry. Bitmovin built the world’s first commercial adaptive streaming player and deployed the first software-defined encoding service that runs on any cloud platform. Its cloud-native technology offers the most flexible and scalable media encoding, playback, and analytics solutions available, with unparalleled device reach, ease of integration, and world-class customer support. Today, the company’s solutions are used by over 400 customers worldwide, including the BBC, ClassPass, Discovery, fuboTV, Hulu and many more. For more information, visit www.bitmovin.com.
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