In my previous post, we discussed two new image formats: High-Efficiency Image File (HEIF) and AV1 Image File (AVIF). In this article, we'll take a closer look at two emerging video formats built on the same foundations.
Akamai Image & Video Manager (IVM) already supports the key video codecs H.264, H.265, VP8, and VP9, as well as containers mp4, mov, and WebM. Let's examine two emerging video formats that are gaining momentum: High-Efficiency Video Codec (HEVC) and AOMedia Video 1 (AV1) formats.
As with new image types, the creation of new video types is driven by three main objectives:
- Better compression that requires fewer bytes delivered for the same quality video
- Enhanced features to support a wider range of use cases within a single video format
- Increased browser support for compatibility with the highest percentage of users
Here's a look at both HEVC and AV1 formats through the lens of these objectives.
The HEVC, also known as H.265, compression standard is a video compression format intended to succeed H.264.
In comparison with H.264, HEVC offers from 25% to 50% better data compression at the same level of video quality or substantially improved video quality at the same bit rate.
HEVC provides a robust set of advanced features among video formats, including:
- Support for resolutions up to 8192x4320, including 8K UHD
- Much less risk of artifacts (other than blur)
- Better picture quality in terms of noise level, color spaces, and dynamic range
- Improved parallel processing methods
One limitation of this format is that support is limited to Apple devices. Almost only Safari and iOS apps will be able to use it. If you have many iPhone or Mac users, you can include it with a fallback to H264. The experience for Apple users will be better.
Even with hardware acceleration -- available almost only in Apple devices -- the higher complexity of this format means that encoding is significantly slower, so producing the variants for delivery takes more compute cycles and more time. Since HEVC usage incurs royalties, and other formats (such as AV1) are gaining significant momentum, we recommend being careful about investing significant resources into this video format.
AV1 is a royalty-free video format by the Alliance for Open Media (AOM) meant to succeed its predecessor VP9 and to compete with the HEVC/H.265 format.
The partners involved in the AOM that created the format make the case for widespread support in the near future:
As you can see, Apple quietly and surprisingly joined the AOM in early 2018, so it will be interesting to see what this means for HEVC. In addition, HEVC requires licensing fees, but AV1 does not -- which makes it even more likely that AV1 will come out as the long-term winner.
AV1 delivers similar or slightly higher gains in compression efficiency compared with H265, while being license-free. The following benchmark shows a comparison of AV1 versus its main competitors:
Source: MSU Video Group
Some of the AV1 advanced features include:
- No royalties
- Scales to any modern device at any bandwidth
- Developed for the internet and related applications and services -- from browsers and streaming to video conferencing services
- Designed with a low computational footprint and optimized for hardware
A limitation of this format is its current lack of support for MacOS and iOS, however, as stated above, Apple joined the AOM in early 2018. AV1 provides support for Chrome, Firefox, Edge, and Opera.
In a significant recent development, Netflix announced in February 2020 that it has started to stream titles in AV1 on Android in what could significantly help the two-year-old media codec gain wider adoption. Netflix claims that by switching from Google's VP9 -- which it previously used on Android -- to AV1, its compression efficiency has increased by 20%.
Continue to Innovate
As with images, video optimization is an ever-changing and evolving science. To stay current, it's important to be educated about emerging trends to ensure that you're making informed technology decisions. We also recommend that you ensure your video provider will support these formats sooner than later.