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AV1 — Now Powering 30% of Netflix Streaming

Post Syndicated from Netflix Technology Blog original https://netflixtechblog.com/av1-now-powering-30-of-netflix-streaming-02f592242d80

AV1 — Now Powering 30% of Netflix Streaming

Liwei Guo, Zhi Li, Sheldon Radford, Jeff Watts

Streaming video has become an integral part of our daily lives. At Netflix, our top priority is delivering the best possible entertainment experience to our members, regardless of their devices or network conditions. One of the key technologies enabling this is AV1, a modern, open video codec that is rapidly transforming both how we stream content and how users experience it. Today, AV1 powers approximately 30% of all Netflix viewing, marking a major milestone in our efforts to bring more efficient and higher-quality streaming to our members.

In this post, we’ll revisit Netflix’s AV1 journey to date, highlight emerging use cases, and share adoption trends across the device ecosystem. Having witnessed AV1’s significant impact，and with AV2 on the horizon, we’re more excited than ever about how open codecs will continue to revolutionize streaming for everyone.

AV1: A Modern, Open Codec

Since entering the streaming business in 2007, Netflix has primarily relied on H.264/AVC as its streaming format. However, we quickly recognized that a modern, open codec would benefit not only Netflix, but the entire multimedia industry. In 2015, together with a group of like-minded industry leaders, Netflix co-founded the Alliance for Open Media (AOMedia) to develop and promote next generation, open source media technologies. The AV1 codec became the first major project of this collaboration, with ambitious goals: to deliver significant improvements in compression efficiency over state-of-the-art codecs, and to introduce rich features that enable new use cases. After three years of collaborative development, AV1 was officially released in 2018.

Netflix’s AV1 Journey: From Android to TVs and Beyond

Piloting on Android Mobile

When we first set out to bring AV1 streaming to Netflix members, Android was the ideal starting point. Android’s flexibility allowed us to quickly integrate a software AV1 decoder using the efficient dav1d library, which was already optimized for ARM chipsets in mobile devices.

AV1’s superior compression efficiency was especially valuable for mobile users, many of whom are mindful of their data usage and network conditions. By adopting AV1, we were able to deliver noticeably better video quality at lower bitrates. For members relying on cellular data, this meant crisper images with fewer compression artifacts, even when bandwidth was limited. Launching AV1 support on Android in 2020 marked a significant step forward for Netflix on mobile, making high-quality streaming more accessible and enjoyable for members everywhere.

Front-and-Center for Netflix VOD Streaming

The success of our AV1 launch on Android proved its value for Netflix streaming, motivating us to expand support to smart TVs and other large-screen devices, where most of our members watch their favorite shows.

Smart TVs depend on hardware decoders for efficient high-quality playback. We worked closely with device manufacturers and SoC vendors to certify these devices, ensuring they are both conformant and performant. This collaborative effort enabled our AV1 streaming to TV devices in late 2021. Shortly thereafter, we expanded AV1 streaming to web browsers (in 2022) and continued to broaden device support. In 2023, this included Apple devices with the introduction of AV1 hardware support in the new M3 and A17 Pro chips.

As more devices began shipping with AV1 hardware support, a rapidly growing share of our members could enjoy the benefits of this advanced codec. Combined with our investment in adding AV1 streams across the entire catalog, AV1 viewing share has been consistently increasing in recent years. Today, AV1 accounts for approximately 30% of all Netflix streaming, making it our second most-used codec — and it’s on track to become number one very soon. The payoff has been substantial.

  • Elevating Streaming Experience Across the Board: Large-screen TVs and other devices demand higher bitrates to deliver stunning 4K, high frame rate (HFR) experiences. AV1’s superior compression efficiency has allowed us to provide these experiences using less data, making high-quality streaming more accessible and reliable. On average, AV1 streaming sessions achieve VMAF scores¹ that are 4.3 points higher than AVC and 0.9 points higher than HEVC sessions. At the same time, AV1 sessions use one-third less bandwidth than both AVC and HEVC, resulting in 45% fewer buffering interruptions. Moreover, Netflix’s diverse content catalog benefits universally from AV1, with improvements across all content types.
  • Driving Network Efficiency Worldwide: Netflix streams are delivered through our own content delivery network (Open Connect), in partnership with local ISPs around the globe. With more than 300 million members, Netflix streaming constitutes a non-trivial portion of global internet traffic. Because AV1 is a more efficient codec, its streams are smaller in size (while providing even better visual quality). By shifting a substantial share of our streaming to AV1, we reduce overall internet bandwidth consumption, and lessen system and network load for both Netflix and our partners.

Unlocking Advanced Experiences

In addition to its superior compression efficiency, AV1 was designed to support a rich set of features. Once we established a robust framework for the continuous expansion of AV1 streaming, we quickly shifted our focus towards exploring AV1’s unique features to unlock even more advanced and immersive experiences for our members.

High-Dynamic-Range(HDR)
HDR brings enhanced detail, vivid colors, and greater clarity to images. As a premium streaming service, Netflix has been a pioneer in adopting HDR, offering HDR streaming since 2016. In March 2025, we launched AV1 HDR streaming. We chose HDR10+ as the HDR format for its use of dynamic metadata, which enabled us to adapt the tone mapping per device in a scene-dependent manner.

As anticipated, the combination of AV1 and HDR10+ allows us to deliver images with greater detail, more vibrant colors, and an overall heightened sense of immersion for our members. At the moment, 85% of our HDR catalog (from the perspective of view-hours) has AV1-HDR10+ coverage, and this number is expected to reach 100% in the next couple of months.

Photographs of devices displaying the same (cropped) frame with HDR10 metadata (left) and HDR10+ metadata (right). Notice the preservation of the flashlight detail in the HDR10+ capture, and the over-exposure of the region under the flashlight in the HDR10 one.

Cinematic Film Grain
Film grain is a hallmark of the cinematic experience, widely used in the movie industry to enhance a film’s depth, texture, and realism. However, because film grain is inherently random, faithfully representing it in digital video requires a significant amount of data. This presents a unique challenge for streaming: restricting the bitrate can result in grain that appears unnatural or distorted, while increasing the bitrate to accurately preserve cinematic grain almost inevitably leads to elevated rebuffering. The AV1 specification incorporates a unique solution called Film Grain Synthesis (FGS). Instead of encoding grain as part of every frame, the grain is stripped out before encoding and then resynthesized at the decoder using parameters sent in the bitstream, delivering a realistic cinematic film grain experience without the usual data costs.

This approach represents a significant shift from traditional compression and streaming techniques. Our team invested substantial effort in fine-tuning the media processing pipeline, ensuring FGS delivers robust performance at scale. In July 2025, we successfully productized AV1 FGS, and the results were astonishing: AV1 with FGS could deliver videos with cinematic film grain at a bitrate well within the capabilities of typical household internet connections. For non-FGS AV1 encodings, even at much higher bitrate, they may not be able to achieve comparable quality.

The same (cropped) frame from source (left), regular AV1 stream encoded at 8274kbps (middle) and AV1 FGS stream encoded at 2804 kbps (right). The AV1 FGS stream reduces the bitrate by 66% while delivering clearly better quality.

Beyond VOD Streaming

So far, our AV1 journey has been mainly on VOD, but we see significant opportunities for AV1 beyond traditional VOD streaming. On a mission to entertain the world, Netflix has constantly explored and established other ways to bring joy to our members, and we believe AV1 could contribute to the success of these new products.

Live Streaming
Debuting in 2023, live streaming has experienced rapid growth at Netflix, becoming a key part of our streaming offerings in just two short years. We are actively evaluating the use of AV1 in live streaming, as we believe it could help further scale Netflix’s live programming:

  • Hyper-scale concurrent viewership: Live streaming at Netflix means delivering content to tens of millions of viewers simultaneously. AV1’s superior compression efficiency could significantly reduce the required bandwidth, enabling us to deliver high-quality live experiences to large audiences without compromising video quality.
  • Customizable graphics overlay: for live sport events such as football, tennis and boxing, graphics overlays have become an integral part of the member experience — from embedding game statistics to delivering sponsorships. AV1 offers an opportunity to make the graphics highly customizable: layered coding is supported in AV1’s main profile, allowing encoding the main content in the base layer, and graphics in the enhancement layer, and easily swapping out one version of the enhancement layer with another. We envision that the use of AV1’s layered coding can greatly simplify the live streaming workflow and reduce delivery costs.

Cloud Gaming
Cloud gaming is a new Netflix offering that is currently in the beta phase and is available to members in select countries. The game engines run on cloud servers, while the rendered graphics are streamed directly to members’ devices. By removing barriers and transforming every Netflix-enabled device into a game console, Cloud gaming aims to deliver a seamless, “play anywhere” experience for our members. For a glimpse of this in action, watch as Co-CEO Greg Peters and CTO Elizabeth Stone play a round of Boggle Party — powered entirely by Netflix’s cloud gaming platform!

Unlike traditional video streaming, cloud gaming requires that every player action is reflected instantly on the screen to ensure a responsive and immersive experience. This makes delivering high-quality video frames with extremely low latency, despite fluctuating network conditions, one of the biggest challenges in cloud gaming.

Our team is actively working on productizing AV1 for cloud gaming. Given AV1’s high compression efficiency, we can reduce frame sizes, helping video frames get through even when network conditions become challenging. This positions AV1 as a promising technology for enabling a high-quality, low-latency gaming experience across a wide range of devices.

A Device Ecosystem United for AV1

Netflix is a streaming company, and we have worked diligently to create highly efficient and standards-conformant AV1 streams for our catalog. However, an equally, if not more, important factor in AV1’s success is the widespread support from device manufacturers. Throughout our AV1 journey, we have been impressed by the unprecedented pace at which the device ecosystem has embraced AV1.

Just six months after the AV1 specification was finalized, the open-source AV1 decoder library sponsored by AOM, dav1d, was released. Small, performant, and highly resource-efficient, dav1d bridged the gap for early adopters like Netflix while hardware solutions were still in development. Continuous improvements to its performance and compatibility have made dav1d the preferred choice for a wide range of platforms and practical applications. Today, it serves as Android’s default software decoder. Additionally, it plays a key role in web browsers — for Netflix, it powers approximately 40% of our browser playback. This broad adoption has significantly expanded access to high-quality AV1 streaming, even in the absence of dedicated hardware decoders.

Netflix maintains a close working relationship with device manufacturers and SoC vendors, and we have witnessed first-hand their enthusiasm for adopting AV1. To ensure optimal streaming performance, Netflix has a rigorous certification process to verify proper support for our streaming formats on devices. AV1 was added to this certification process in 2019, and since then, we have seen a steady increase in the number of devices with full AV1 decoding capabilities. Over the past five years (2021–2025), 88% of large-screen devices, including TVs, set-top boxes, and streaming sticks, submitted for Netflix certification have supported AV1, with the vast majority offering full 4K@60fps capability. Notably, since 2023, almost all devices we have received for certification are AV1-capable.

We have also been impressed by the robustness of AV1 implementations across these devices. As mentioned earlier, FGS is an innovative tool that departs from traditional codec architectures and was not included in our initial full-scale AV1 streaming rollout. When we launched FGS this July, we worked closely with our partners to ensure broad device compatibility. We are pleased with the successful progress made, and AV1 with FGS is now supported across a significant and growing number of in-field devices.

Looking Ahead: AV1 Today, AV2 Tomorrow

As we reflect on our AV1 journey, it’s clear that the codec has already transformed the streaming experience for hundreds of millions of Netflix members worldwide. Thanks to industry-wide collaboration and rapid device adoption, AV1 is delivering higher quality, greater efficiency, and new cinematic features to more screens than ever before.

Looking ahead, we are excited about the forthcoming release of AV2, announced by the Alliance for Open Media for the end of 2025. AV2 is poised to set a new benchmark for compression efficiency and streaming capabilities, building on the solid foundation laid by AV1. At Netflix, we remain committed to adopting the best open technologies to delight our members around the globe. While AV2 represents the future of streaming, AV1 is very much the present — serving as the backbone of our platform and powering exceptional entertainment experiences across a vast and ever-expanding ecosystem of devices.

Acknowledgement

The success of AV1 at Netflix is the result of the dedication, expertise, and collaboration of many teams across the company — including Encoding, Clients, Device Certification, Partner Engineering, Data Science & Engineering, Infra, Platform, etc.

We would also like to thank Artem Danylenko, Aditya Mavlankar, Anne Aaron, Cyril Concolato, Allan Zhou and Anush Moorthy for their valuable comments and feedback on earlier drafts of this post.

Footnotes

  1. These numbers represent a snapshot of data from November 13, 2025. Actual values may vary slightly from day to day and across different regions, depending on the mix of content, devices, and internet connectivity.

AV1 — Now Powering 30% of Netflix Streaming was originally published in Netflix TechBlog on Medium, where people are continuing the conversation by highlighting and responding to this story.

HDR10+ Now Streaming on Netflix

Post Syndicated from Netflix Technology Blog original https://netflixtechblog.com/hdr10-now-streaming-on-netflix-c9ab1f4bd72b

Roger Quero, Liwei Guo, Jeff Watts, Joseph McCormick, Agata Opalach, Anush Moorthy

We are excited to announce that we are now streaming HDR10+ content on our service for AV1-enabled devices, enhancing the viewing experience for certified HDR10+ devices, which previously only received HDR10 content. The dynamic metadata included in our HDR10+ content improves the quality and accuracy of the picture when viewed on these devices.

Delighting Members with Even Better Picture Quality

Nearly a decade ago, we made a bold move to be a pioneering adopter of High Dynamic Range (HDR) technology. HDR enables images to have more details, vivid colors, and improved realism. We began producing our shows and movies in HDR, encoding them in HDR, and streaming them in HDR for our members. We were confident that it would greatly enhance our members’ viewing experience, and unlock new creative visions — and we were right! In the last five years, HDR streaming has increased by more than 300%, while the number of HDR-configured devices watching Netflix has more than doubled. Since launching HDR with season one of Marco Polo, Netflix now has over 11,000 hours of HDR titles for members to immerse themselves in.

We continue to enhance member joy while maintaining creative vision by adding support for HDR10+. This will further augment Netflix’s growing HDR ecosystem, preserve creative intent on even more devices, and provide a more immersive viewing experience.

We enabled HDR10+ on Netflix using the AV1 video codec that was standardized by the Alliance for Open Media (AOM) in 2018. AV1 is one of the most efficient codecs available today. We previously enabled AV1 encoding for SDR content, and saw tremendous value for our members, including higher and more consistent visual quality, lower play delay and increased streaming at the highest resolution. AV1-SDR is already the second most streamed codec at Netflix, behind H.264/AVC, which has been around for over 20 years! With the addition of HDR10+ streams to AV1, we expect the day is not far when AV1 will be the most streamed codec at Netflix.

To enhance our offering, we have been adding HDR10+ streams to both new releases and existing popular HDR titles. AV1-HDR10+ now accounts for 50% of all eligible viewing hours. We will continue expanding our HDR10+ offerings with the goal of providing an HDR10+ experience for all HDR titles by the end of this year¹.

Industry Adopted Formats

Today, the industry recognizes three prevalent HDR formats: Dolby Vision, HDR10, and HDR10+. For all three HDR Formats, metadata is embedded in the content, serving as instructions to guide the playback device — whether it’s a TV, mobile device, or computer — on how to display the image.

HDR10 is the most widely adopted HDR format, supported by all HDR devices. HDR10 uses static metadata that is defined once for the entire content detailing aspects such as the maximum content light level (MaxCLL), maximum frame average light level (MaxFALL), as well as characteristics of the mastering display used for color grading. This metadata only allows for a one-size-fits-all tone mapping of the content for display devices. It cannot account for dynamic contrast across scenes, which most content contains.

HDR10+ and Dolby Vision improve on this with dynamic metadata that provides content image statistics on a per-frame basis, enabling optimized tone mapping adjustments for each scene. This achieves greater perceptual fidelity to the original, preserving creative intent.

HDR10 vs. HDR10+

The figure below shows screen grabs of two AV1-encoded frames of the same content displayed using HDR10 (top) and HDR10+ (bottom).

Photographs of devices displaying the same frame with HDR10 metadata (top) and HDR10+ metadata (bottom). Notice the preservation of the flashlight detail in the HDR10+ capture, and the over-exposure of the region under the flashlight in the HDR10 one².

As seen in the flashlight on the table, the highlight details are clipped in the HDR10 content, but are recovered in HDR10+. Further, the region under the flashlight is overexposed in the HDR10 content, while HDR10+ renders that region with greater fidelity to the source. The reason HDR10+, with its dynamic metadata, shines in this example is that the scenes preceding and following the scene with this frame have markedly different luminance statistics. The static HDR10 metadata is unable to account for the change in the content. While this is a simple example, the dynamic metadata in HDR10+ demonstrates such value across any set of scenes. This consistency allows our members to stay immersed in the content, and better preserves creative intent.

Receiving HDR10+

At the time of launch, these requirements must be satisfied to receive HDR10+:

1.Member must have a Netflix Premium plan subscription

2. Title must be available in HDR10+ format

3. Member device must support AV1 & HDR10+. Here are some examples of compatible devices:

  • SmartTVs, mobile phones, and tablets that meet Netflix certification for HDR10+
  • Source device (such as set-top boxes, streaming devices, MVPDs, etc.) that meets Netflix certification for HDR10+, connected to an HDR10+ compliant display via HDMI

4. For TV or streaming devices, ensure that the HDR toggle is enabled in our Netflix application settings: https://help.netflix.com/en/node/100220

Additional guidance: https://help.netflix.com/en/node/13444

Summary

More HDR content is watched every day on Netflix. Expanding the Netflix HDR ecosystem to include HDR10+ increases the accessibility of HDR content with dynamic metadata to more members, improves the viewing experience, and preserves the creative intent of our content creators. The commitment to innovation and quality underscores our dedication to delivering an immersive and authentic viewing experience for all our members.

Acknowledgements

Launching HDR10+ was a collaborative effort involving multiple teams at Netflix, and we are grateful to everyone who contributed to making this idea a reality. We would like to extend our thanks to the following teams for their crucial roles in this launch:

  • The various Client and Partner Engineering teams at Netflix that manage the Netflix experience across different device platforms.
    Special acknowledgments: Akshay Garg, Dasha Polyakova, Vivian Li, Ben Toofer, Allan Zhou, Artem Danylenko
  • The Encoding Technologies team that is responsible for producing optimized encodings to enable high-quality experiences for our members. Special acknowledgments: Adithya Prakash, Vinicius Carvalho
  • The Content Operations & Innovation teams responsible for producing and delivering HDR content to Netflix, maintaining the intent of creative vision from production to streaming. Special acknowledgements: Michael Keegan

Footnotes

  1. While we have enabled HDR10+ for distribution i.e., for what our members consume on their devices, we continue to accept only Dolby Vision masters on the ingest side, i.e., for all content delivery to Netflix as per our delivery specification. In addition to HDR10+, we continue to serve HDR10 and DolbyVision. Our encoding pipeline is designed with flexibility and extensibility where all these HDR formats could be derived from a single DolbyVision deliverable efficiently at scale.
  2. We recognize that it is hard to convey visual improvements in HDR video using still photographs converted to SDR. We encourage the reader to stream Netflix content in HDR10+ and check for yourself!

HDR10+ Now Streaming on Netflix was originally published in Netflix TechBlog on Medium, where people are continuing the conversation by highlighting and responding to this story.

Bringing AV1 Streaming to Netflix Members’ TVs

Post Syndicated from Netflix Technology Blog original https://netflixtechblog.com/bringing-av1-streaming-to-netflix-members-tvs-b7fc88e42320

by Liwei Guo, Ashwin Kumar Gopi Valliammal, Raymond Tam, Chris Pham, Agata Opalach, Weibo Ni

AV1 is the first high-efficiency video codec format with a royalty-free license from Alliance of Open Media (AOMedia), made possible by wide-ranging industry commitment of expertise and resources. Netflix is proud to be a founding member of AOMedia and a key contributor to the development of AV1. The specification of AV1 was published in 2018. Since then, we have been working hard to bring AV1 streaming to Netflix members.

In February 2020, Netflix started streaming AV1 to the Android mobile app. The Android launch leveraged the open-source software decoder dav1d built by the VideoLAN, VLC, and FFmpeg communities and sponsored by AOMedia. We were very pleased to see that AV1 streaming improved members’ viewing experience, particularly under challenging network conditions.

While software decoders enable AV1 playback for more powerful devices, a majority of Netflix members enjoy their favorite shows on TVs. AV1 playback on TV platforms relies on hardware solutions, which generally take longer to be deployed.

Throughout 2020 the industry made impressive progress on AV1 hardware solutions. Semiconductor companies announced decoder SoCs for a range of consumer electronics applications. TV manufacturers released TVs ready for AV1 streaming. Netflix has also partnered with YouTube to develop an open-source solution for an AV1 decoder on game consoles that utilizes the additional power of GPUs. It is amazing to witness the rapid growth of the ecosystem in such a short time.

Today we are excited to announce that Netflix has started streaming AV1 to TVs. With this advanced encoding format, we are confident that Netflix can deliver an even more amazing experience to our members. In this techblog, we share some details about our efforts for this launch as well as the benefits we foresee for our members.

Enabling Netflix AV1 Streaming on TVs

Launching a new streaming format on TV platforms is not an easy job. In this section, we list a number of challenges we faced for this launch and share how they have been solved. As you will see, our “highly aligned, loosely coupled” culture played a key role in the success of this cross-functional project. The high alignment guides all teams to work towards the same goals, while the loose coupling keeps each team agile and fast paced.

Challenge 1: What is the best AV1 encoding recipe for Netflix streaming?

AV1 targets a wide range of applications with numerous encoding tools defined in the specification. This leads to unlimited possibilities of encoding recipes and we needed to find the one that works best for Netflix streaming.

Netflix serves movies and TV shows. Production teams spend tremendous effort creating this art, and it is critical that we faithfully preserve the original creative intent when streaming to our members. To achieve this goal, the Encoding Technologies team made the following design decisions about AV1 encoding recipes:

  • We always encode at the highest available source resolution and frame rate. For example, for titles where the source is 4K and high frame rate (HFR) such as “Formula 1: Drive to Survive”, we produce AV1 streams in 4K and HFR. This allows us to present the content exactly as creatively envisioned on devices and plans which support such high resolution and frame-rate playback.
  • All AV1 streams are encoded with 10 bit-depth even if AV1 Main Profile allows both 8 and 10 bit-depth. Almost all movies and TV shows are delivered to Netflix at 10 or higher bit-depth. Using 10-bit encoding can better preserve the creative intent and reduce the chances of artifacts (e.g., banding).
  • Dynamic optimization is used to adapt the recipe at the shot level and intelligently allocate bits. Streams on the Netflix service can easily be watched millions of times, and thus the optimization on the encoding side goes a long way in improving member experience. With dynamic optimization, we allocate more bits to more complex shots to meet Netflix’s high bar of visual quality, while encoding simple shots at the same high quality but with much fewer bits.

Challenge 2: How do we guarantee smooth AV1 playback on TVs?

We have a stream analyzer embedded in our encoding pipeline which ensures that all deployed Netflix AV1 streams are spec-compliant. TVs with an AV1 decoder also need to have decoding capabilities that meet the spec requirement to guarantee smooth playback of AV1 streams.

To evaluate decoder capabilities on these devices, the Encoding Technologies team crafted a set of special certification streams. These streams use the same production encoding recipes so they are representative of production streams, but have the addition of extreme cases to stress test the decoder. For example, some streams have a peak bitrate close to the upper limit allowed by the spec. The Client and UI Engineering team built a certification test with these streams to analyze both the device logs as well as the pictures rendered on the screen. Any issues observed in the test are flagged on a report, and if a gap in the decoding capability was identified, we worked with vendors to bring the decoder up to specification.

Challenge 3: How do we roll out AV1 encoding at Netflix scale?

Video encoding is essentially a search problem — the encoder searches the parameter space allowed by all encoding tools and finds the one that yields the best result. With a larger encoding tool set than previous codecs, it was no surprise that AV1 encoding takes more CPU hours. At the scale that Netflix operates, it is imperative that we use our computational resources efficiently; maximizing the impact of the CPU usage is a key part of AV1 encoding, as is the case with every other codec format.

The Encoding Technologies team took a first stab at this problem by fine-tuning the encoding recipe. To do so, the team evaluated different tools provided by the encoder, with the goal of optimizing the tradeoff between compression efficiency and computational efficiency. With multiple iterations, the team arrived at a recipe that significantly speeds up the encoding with negligible compression efficiency changes.

Besides speeding up the encoder, the total CPU hours could also be reduced if we can use compute resources more efficiently. The Performance Engineering team specializes in optimizing resource utilization at Netflix. Encoding Technologies teamed up with Performance Engineering to analyze the CPU usage pattern of AV1 encoding and based on our findings, Performance Engineering recommended an improved CPU scheduling strategy. This strategy improves encoding throughput by right-sizing jobs based on instance types.

Even with the above improvements, encoding the entire catalog still takes time. One aspect of the Netflix catalog is that not all titles are equally popular. Some titles (e.g., La Casa de Papel) have more viewing than others, and thus AV1 streams of these titles can reach more members. To maximize the impact of AV1 encoding while minimizing associated costs, the Data Science and Engineering team devised a catalog rollout strategy for AV1 that took into consideration title popularity and a number of other factors.

Challenge 4: How do we continuously monitor AV1 streaming?

With this launch, AV1 streaming reaches tens of millions of Netflix members. Having a suite of tools that can provide summarized metrics for these streaming sessions is critical to the success of Netflix AV1 streaming.

The Data Science and Engineering team built a number of dashboards for AV1 streaming, covering a wide range of metrics from streaming quality of experience (“QoE”) to device performance. These dashboards allow us to monitor and analyze trends over time as members stream AV1. Additionally, the Data Science and Engineering team built a dedicated AV1 alerting system which detects early signs of issues in key metrics and automatically sends alerts to teams for further investigation. Given AV1 streaming is at a relatively early stage, these tools help us be extra careful to avoid any negative member experience.

Quality of Experience Improvements

We compared AV1 to other codecs over thousands of Netflix titles, and saw significant compression efficiency improvements from AV1. While the result of this offline analysis was very exciting, what really matters to us is our members’ streaming experience.

To evaluate how the improved compression efficiency from AV1 impacts the quality of experience (QoE) of member streaming, A/B testing was conducted before the launch. Netflix encodes content into multiple formats and selects the best format for a given streaming session by considering factors such as device capabilities and content selection. Therefore, multiple A/B tests were created to compare AV1 with each of the applicable codec formats. In each of these tests, members with eligible TVs were randomly allocated to one of two cells, “control” and “treatment”. Those allocated to the “treatment” cell received AV1 streams while those allocated to the “control” cell received streams of the same codec format as before.

In all of these A/B tests, we observed improvements across many metrics for members in the “treatment” cell, in-line with our expectations:

Higher VMAF scores across the full spectrum of streaming sessions

  • VMAF is a video quality metric developed and open-sourced by Netflix, and is highly correlated to visual quality. Being more efficient, AV1 delivers videos with improved visual quality at the same bitrate, and thus higher VMAF scores.
  • The improvement is particularly significant among sessions that experience serious network congestion and the lowest visual quality. For these sessions, AV1 streaming improves quality by up to 10 VMAF without impacting the rebuffer rate.

More streaming at the highest resolution

  • With higher compression efficiency, the bandwidth needed for streaming is reduced and thus it is easier for playback to reach the highest resolution for that session.
  • For 4K eligible sessions, on average, the duration of 4K videos being streamed increased by about 5%.

Fewer noticeable drops in quality during playback

  • We want our members to have brilliant playback experiences, and our players are designed to adapt to the changing network conditions. When the current condition cannot sustain the current video quality, our players can switch to a lower bitrate stream to reduce the chance of a playback interruption. Given AV1 consumes less bandwidth for any given quality level, our players are able to sustain the video quality for a longer period of time and do not need to switch to a lower bitrate stream as much as before.
  • On some TVs, noticeable drops in quality were reduced by as much as 38%.

Reduced start play delay

  • On some TVs, with the reduced bitrate, the player can reach the target buffer level sooner to start the playback.
  • On average, we observed a 2% reduction in play delay with AV1 streaming.

Next Steps

Our initial launch includes a number of AV1 capable TVs as well as TVs connected with PS4 Pro. We are working with external partners to enable more and more devices for AV1 streaming. Another exciting direction we are exploring is AV1 with HDR. Again, the teams at Netflix are committed to delivering the best picture quality possible to our members. Stay tuned!

Acknowledgments

This is a collective effort with contributions from many of our colleagues at Netflix. We would like to thank

  • Andrey Norkin and Cyril Concolato for providing their insights about AV1 specifications.
  • Kyle Swanson for the work on reducing AV1 encoding complexity.
  • Anush Moorthy and Aditya Mavlankar for fruitful discussions about encoding recipes.
  • Frederic Turmel and his team for managing AV1 certification tests and building tools to automate device verification.
  • Susie Xia for helping improve resource utilization of AV1 encoding.
  • Client teams for integrating AV1 playback support and optimizing the experience.
  • The Partner Engineering team for coordinating with device vendors and investigating playback issues.
  • The Media Cloud Engineering team for accommodating the computing resources for the AV1 rollout.
  • The Media Content Playback team for providing tools for AV1 rollout management.
  • The Data Science and Engineering team for A/B test analysis, and for providing data to help us continuously monitor AV1.

If you are passionate about video technologies and interested in what we are doing at Netflix, come and chat with us! The Encoding Technologies team currently has a number of openings, and we can’t wait to have more stunning engineers joining us.

Senior Software Engineer, Encoding Technologies

Senior Software Engineer, Video & Image Encoding

Senior Software Engineer, Media Systems

Bringing AV1 Streaming to Netflix Members’ TVs was originally published in Netflix TechBlog on Medium, where people are continuing the conversation by highlighting and responding to this story.