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Netflix Uses AI in Its New Codec To Compress Video Scene By Scene (qz.com)
An anonymous reader shares a Quartz report: Annoying pauses in your streaming movies are going to become less common, thanks to a new trick Netflix is rolling out. It's using artificial intelligence techniques to analyze each shot in a video and compress it without affecting the image quality, thus reducing the amount of data it uses. The new encoding method is aimed at the growing contingent of viewers in emerging economies who watch video on phones and tablets. "We're allergic to rebuffering," said Todd Yellin, a vice president of innovation at Netflix. "No one wants to be interrupted in the middle of Bojack Horseman or Stranger Things." Yellin hopes the new system, called Dynamic Optimizer, will keep those Netflix binges free of interruption when it's introduced sometime in the next "couple of months." He was demonstrating the system's results at "Netflix House," a mansion in the hills overlooking Barcelona that the company has outfitted for the Mobile World Congress trade show. In one case, the image quality from a 555 kilobits per second (kbps) stream looked identical to one on a data link with half the bandwidth.
What I think is that they devised an algorithm, probably based on neural networks, that is particularly good as estimating the perceived quality of the picture.
This data is then used to adjust the level of compression of each part of the picture, so that the least important parts of the picture get compressed more aggressively to save bitrate for the more important parts.
This is nothing new really, the idea of using AI techniques and perceived quality to help with compression is decades old. The interesting part here is that it is done on a commercial scale.
Bear in mind that while they may be using a new codec - that is, a piece of code designed to convert a video from one format to another - they're not using a new format, if they did, then they could no longer use the hardware acceleration they pretty much rely upon to ensure devices can play their content in real time, and without destroying the battery.
So insofar as they're doing the above, they're not doing it any more than any other codec does, because only compressing changes is what every current codec does well, and pretty much a fundamental assumption behind each mainstream format, from MPEG-1 and H.261 onwards.
You are not alone. This is not normal. None of this is normal.
Netflix does use AI in developing the video compression algorithm. The problem with encoding videos with lossy algorithms is that video quality is a subjective thing. You need a person to watch it and tell you how good the video quality looks. This makes it rather slow and difficult to do A/B testing, not to mention how boring it is watching the same clips over and over with different encoding.
Netflix got around the problem by using machine learning to teach a computer when video quality looked good. They had a bunch of people watch videos with different compression and rate the quality, then told the AI that their ratings were gospel. It then analyzed the different videos and decided for itself which features were associated with good quality. Once the computer was generating the video ratings as people, they had a rapid way to do A/B testing. That allowed them to optimize their compression algorithm in much less time than with using humans to rate video quality.
I'm not sure why Summary links to some popular news article which talks in general about Netflix using AI, instead of linking to the actual Netflix page describing exactly what they did. This used to be the sort of technical detail you'd expect from slashdot submissions.
I hate these things, they never work as stated. All it means is they can save money by buffering ahead even less. Days past if you had a poor connection you could load a video and pause it and it would buffer through. Now if you pause it buffers what it seems to think is all you actually need. It never is.