Intel's AV1 Encoder Is An Ace For Arc In Game Streaming Versus NVIDIA And AMD

Intel Arc Laptops Hero
If you've ever done any livestreaming on the internet, then you already know that one of the most important technical aspects of doing so is properly configuring your stream settings. Your selection of video encoder and its bitrate can have a particular influence. Most folks streaming these days are using the open-source Open Broadcaster Software (OBS) and its built-in x264 software encoder. This CPU-based software encoder is generally considered to give better results at the same bitrate compared to GPU-based hardware encoders.

In reality, given that you're almost-assuredly not using the highest-quality presets for x264, the difference is probably pretty small. Certainly, the difference between x264 and a hardware AVC encoder is much smaller than the difference between AVC itself and the free-and-open-source AV1 codec. AV1 is a next-generation video codec that provides improved compression ratios compared to H.264 and even H.265. That means superior video quality at the same bitrate.

intel arc av1 vs h264 comparison
AV1 vs. H.264 comparison image from Intel.

Nobody is using AV1 for livestreaming yet, and there are two reasons for that. One is simply that it is too complex for all but the fastest CPUs to encode in "real-time." That means continuously encoding the video stream at its full frame rate, something that is obviously necessary for live streaming. We can work around that problem by using a hardware encoder, but neither NVIDIA nor AMD can encode AV1 video with their GPUs. There are video cards that can, though, and those are Intel's fledgling Arc GPUs.

YouTuber EposVox, the self-described "Stream Professor," has done a great many videos dissecting the differences between video encoders and their settings. If you're an aspiring livestreamer, you would do well to check out his content, but particularly this latest video, where he got ahold of a Gunnir Arc A380 Photon card and tested Intel's AV1 encoder.

For folks who don't feel like finishing the 16-minute video, we'll lay it out for you: In EposVox's testing, at higher bitrates like 6 Mbps and 8 Mbps, the Intel AV1 encoder in the Arc A380 produces similar quality to x264 in its "veryslow" preset. That's impressive, as x264 has had a decade of optimizations and tweaks while Arc is a brand-new product with self-admitted unripe drivers. The "veryslow" preset for x264 is too demanding for almost any PC to do in real-time, so this is pretty much a straight win for Intel.

eposvox vmaf intel arc av1
VMAF is a psychovisual video quality metric created by Netflix.

However, the results at 3.5 Mbps—a more realistic upload speed for a majority of the world—are even more impressive. At this low bitrate, encoding 1080p60 video usually results in a blocky, blurry mess. Intel's AV1 encoder produces a relatively clean video compared to x264—and both of these options utterly obliterate NVIDIA and AMD's GPU encoders, which seriously struggle with too-low bitrates.

These results are encouraging for Arc, as the AV1 codec is a real step up over the older H.264 and even the H.265 HEVC format. However, you may recall that we mentioned there are two reasons that nobody's using AV1 for livestreaming. The second reason is because there are no websites that support ingestion of AV1 video in real-time. In other words, even if you can encode it quickly, you can't use it for livestreaming.

4way eposvox codec comparison
Unfortunately, YouTube's transocding makes this comparison hard to appreciate.

Does that mean Arc's AV1 encoding ability is useless? No, not even close. AV1 video is still a preferable option for uploading to the internet, and YouTube in particular—YouTube uses the AV1 codec internally, so if you upload in AV1, your videos will complete the "conversion" process super-fast, meaning HD video is ready sooner. Plus, your actual uploads can be significantly smaller thanks to the superior compression ratios offered by AV1.

Besides, it's not likely to be much longer before someone figures out a way to use AV1 for livestreaming. The benefits, particularly at low bitrates, are too big to ignore for long. We expect AMD and NVIDIA to have AV1 encoding integrated in their GPUs sooner than later, but this is still a win for Arc in the interim.