Skip to main content

Netflix Dynamically Adjusts Bitrates to Match 4K Content

(Image credit: Netflix)

LOS GATOS, Calif.—Netflix has developed algorithms that dynamically adjust the bitrate to match the content being streamed by viewers.

The idea is that if a viewer watches 4K or HDR content, the bitrate drops. The company describes this process as “optimized shot-based encodes” for 4K.

The blog gives an example of a 4K animation title episode, where a 640×480 encoding resolution is paired with a 4:3 PAR to achieve 16:9 DAR.

According to Netflix, the new process will enable it to reduce the average bitrate by 50% with no loss in image quality. It adds that viewers who have a limited bandwidth will also get a better image quality.

It also adds that the number of rebuffers per hour is expected to reduce by over 65%; while the reduced bitrate together with some Digital Rights Management (DRM) system improvements result in reducing the initial play delay by about 10%.

Netflix said it has started re-encoding the 4K titles in its catalog in order to generate the optimized streams and expects to complete the process in a couple of months. The streamer continues to work on applying similar optimizations to its HDR streams.

The blog goes into the process in much more detail.