December 16, 2015

Netflix to tweak compression algorithms in 2016

Am I the only one who is a little sceptical about compression advances? Despite Netflixes assurances that their tweaking of the bitrate won't be perceptible I'm more of the opinion that these changes can diminish the quality of picture and sound for the sake of economy.
Large patches of color, like the kind found in children's cartoons, don't actually need a very high bitrate to look really good. What Netflix will do in 2016 and beyond is create specific recipes on a per show basis that will enable some shows with less visual data to use lower bitrates but still come through at 1080p quality. That means going back through its entire backlog of shows and creating new rules for every individual show.
In an example provided by Netflix, the company said that in order to get a crystal-clear 1080p stream in the past might require a bitrate of 5800 kbps. Using the new algorithm, Netflix can achieve the same quality with around a 4640 kbps file, effectively reducing the overall bandwidth needed by 20%. 
[more details on TechRadar]

1 comment:

Dannysat said...

Sounds dubious to me. Having some expertise in this field I would normally say the requirements are set by the device you are watching on. A tablet requires less bit rate and output size than an LED TV.

Seems an odd move in the shadow of 4K TV unless they need extra bandwidth for that type of content.