Microsoft has announced that it will add hardware acceleration support for the Aomedia Video 1 (AV1) video codec to Windows 10 this fall. AV1 is an open, royalty-free codec intended to provide high-quality internet video at higher compression rates than those achieved by standards like H.264 and VP9. Typical quoted figures are a 50 percent compression improvement over H.264 and 20 percent over VP9.
There’s a caveat to this announcement, as our sister site PCMag notes: Very limited hardware support. Up until now, it hasn’t mattered that Windows 10 only implemented AV1 in software, because there were no AV1-supporting GPUs to handle decode in the first place. Hardware support for AV1 decode requires a GPU based on Intel’s Xe, an Nvidia RTX 30-series GPU, or an AMD Radeon RX 6000 GPU. All of these are very new, to the point that the 6000 series of cards hasn’t even been released yet.
Secondary requirements include that you be running Windows 1909 or later, have the AV1 video extension installed, and that your web browser has AV1 hardware support built-in.
AV1 is important because it substantially improves on the compression of older open-source, freely available codecs. The question of how it performs against HEVC (H.265) seems to be an open one — there are a handful of benchmarks available suggesting it’s roughly on par with HEVC, though different comparisons come to somewhat different results.
Codecs like HEVC are heavily encumbered by commercial patents and cannot be played in a browser like Firefox unless Firefox pays a licensing fee to the appropriate patent holders. AV1 was launched by Amazon, Cisco, Google, Intel, Microsoft, Mozilla, and Netflix with a specific focus on delivering high-quality web video. As the benchmark above shows, VVC (h.266) provides even better results than H.265 or AV1, but VVC is also patent-encumbered and requires royalty payments. AV1 is the replacement project that supplanted Google’s VP10 and is specifically designed for real-time applications and higher resolutions than those typically supported by H.264 or VP9. It’s the spiritual descendent of Theora — an open-source codec intended to provide a royalty-free web standard for handling online video.
With support integrated into Windows 10 and hardware support not far behind, Netflix and other streaming services will have a royalty-free method of distributing content that doesn’t carry the patent entanglements or problems of H.265. It’s not clear if any major services intend to switch to AV1 immediately, but the option to lower yearly license payments will surely be attracted to at least some companies.