Netflix is taking steps aimed at upgrading the viewer experience, rolling out AV1 Film Grain Synthesis (FGS) streams to the majority of its subscribers. While FGS has been part of the AV1 standard since the Alliance for Open Media introduced the format in 2018, Netflix began to apply it to a limited number of titles in 2021 and is is now enabling it at scale. The streamer says the open-source FGS compression system “revolutionizes video streaming” and will “preserve the artistic integrity of film grain” — a feature generally considered essential to achieving a cinematic look — while also optimizing data efficiency.

The AV1 Film Grain Synthesis tool uses an auto-regressive (AR) model to preserve the look of film grain for digital streaming. Grain is removed during encoding, reducing the file size for a more efficient transmission at lower bit rates.

The transmission includes metadata with a statistical analysis of the grain, taking into account characteristics like intensity, size, direction and pattern. The technique “handily improves playback stability, while reducing errors and rebuffering,” writes TechRadar.

Netflix explains the process in a technical blog post, describing the “scaling function” employed to control the grain’s appearance under varying lighting conditions and includes visual examples showing improved quality at reduced bitrates using a demo frame from the Netflix title “They Cloned Tyrone.”

TechRadar points out that FGS is an improvement because “movies filmed on digital cameras can appear too clean and perfect, and even digitized versions of analog films can struggle to properly retain the grain.” This is especially true of material shot for Netflix, due to the compression required to stream at volume.

TV Technology reports Netflix’s A/B testing with FGS technology revealed “a smoother and more reliable Quality of Experience (QoE), including lower and average bitrate, decreased playback errors, 10 percent fewer rebuffers, 10 percent fewer noticeable bitrate drops and a 10 percent reduction in the time users spend adjusting their playback position during video playback, likely influenced by reduced bitrate and rebuffering.”

“The subtle dance of film grain adds a layer of authenticity and nostalgia to every scene,” Netflix suggests, calling the granular signature “a key role in storytelling” that enhances depth and reinforces realism.

Netflix recommends “The Hot Spot,” “Kung Fu Cult Master,” “Initial D” and “Dept. Q” among the titles that benefit from FGS capabilities.