What is an HEVC H.265 Encoder, and What Does it Do?
You’re here to learn what an HEVC/H.265 encoder is, and what it does. Maybe you’d also like to know when you’d need one, and why.
Let’s jump right into it then. You’ll learn what HEVC/H.265 is, when you’d need a hardware version of an HEVC encoder, and why you’d use one.
What is HEVC/H.265?
For quite a few years now, H.264 encoding has been the standard for video transport over the internet. But as resolutions get bigger, bandwidth becomes more available, and the demand for higher-quality video increased, a new level of compression was needed.
Building on the concepts behind H.264 compression, a team was assembled to develop a new standard, which was first published in June of 2013, and was called High Efficiency Video Encoding (HEVC) or H.265.
In essence, HEVC takes the same quality video that you’d compress with H.264 and compresses it even further.
The danger in further compression is that you can end up with lower-quality video being viewed at the receiving end, so in order to meet the needs of high-quality video, HEVC had to take the original concepts of H.264 and build on them by making better decisions about what to compress, and how. HEVC is more demanding, both on the encoding side, and on the decoding side, from a computing point of view, but is a much more intelligent way of encoding video.
It looks for spatial repetition within frames, and seeks out opportunities to not have to send the same information over a series of frames. Instead of sending every single image in a sequence, it can send the first full frame, and if there are repetitions within spaces in that frame, they don’t need to be sent again, lowering the total size of the file being sent.
Basically, the more the compression algorithm searches, the more accurate it can be. The more frames you can reference, the more accurate you can be, as well. It’s a matter of increasing the level of complexity of how you estimate motion, spatial resolutions, and other information that can be repeated without having to send that information with every frame.
By not having to send all of the raw data, the decoder translates the messages and files it receives from the encoder, and resolves the video to give you the same high quality stream as the original.
When do I need a hardware encoder?
The average video streamer using a live streaming service can often get away with using software encoding. Software encoders can compress video, however, hardware encoders are turnkey devices dedicated solely to the fast and efficient encoding of your video stream. They’ll have better processing power, use high-quality video inputs like SDI and HDMI, and will allow you to stream higher-quality video at lowered bandwidth rates.
For the most part, HEVC hardware encoders are used by professionals. For example, a broadcaster may employ the use of an encoder in a remote location in order to conduct an interview in real time for broadcast on television.
Another example would be a big business like LinkedIn using an encoder to be able to conduct town hall meetings with participants in different geographical locations, all joining the live stream in near real time (it’s essentially real time, with delays of ~250ms), and with high-quality video contribution that can be produced from one location.
Taking encoding to the next level
One of the tools that broadcasters and enterprise video pros alike are using in their workflows to increase quality and lower bandwidth is Secure Reliable Transport (SRT). SRT is open-source software that optimizes streaming performance even in a situation where you might be streaming over an unpredictable or unknown network.
Despite clever compression tools like HEVC/H.265, unreliable networks can increase video latency, and cause jitter and packet loss, lowering the quality of the video at the receiving end. As an open-source project with no licensing fees, its goal is to help everyone reduce latency and increase quality, no matter the network they’re sending video over.
A new compression standard is already being developed, with a target of reducing HEVC’s current bitrate by half, that has a target date of October, 2020. Other compression standards are emerging, and the race is on to ensure that anyone consuming video, no matter what device they’re using, will be able to get the highest quality with the lowest impact on bandwidth requirements.
You can learn more about hardware encoders in our white paper, “What to Consider Before Buying an HEVC Encoder”. Download it for free here!