Online video on demand Netflix has reached the end of a four-year project to add intelligence to its video encoding and reduce file sizes by around 20 percent. According to Variety, Netflix engineers realized in 2011 that the adaptive encoding presets it used were wasteful, as they encoded simple animated programs and big-budget action movies in the same way. That meant that watching a cartoon in HD carried the same bandwidth demands as a Hollywood blockbuster.
Netflix has rigorously tested newly encoded files to ensure that viewers get an identical image. The company should complete re-encoding its vast video library by the end of Q1 2016. After that, it may dive into an even larger encoding project: re-encoding movies and shows on a scene-by-scene basis, since even within a title some scenes are more visually demanding than others.
Source : Streaming Media