It is estimated that half of all Internet traffic is now video, putting significant pressure on existing infrastructure. The proliferation of mobile devices and the rise of 4K technology point to an even more complex future, so besides improving hardware, it is also necessary to optimize software. With that in mind, YouTube has decided to accelerate video encoding under the open source VP9 codec, which cuts bandwidth usage in half without losing quality... in theory.
The Context
A couple of years ago we were convinced that 4K resolution was a true madness. Today we are passing the first third of 2015, and the truth is that the price of 4K screens keeps falling. Mobile devices have adopted staggering resolution parameters, to the point that any high-end smartphone offers more pixels than the screen I am looking at while writing these lines. Of course, the availability of 4K content is another story... but its encounter with the Internet and streaming services is inevitable. The problem is that video already generates half of the traffic, including Netflix and YouTube. The number of users keeps growing, and infrastructure upgrades are slower than we would like. The masterminds at YouTube are sure that a more efficient use of bandwidth should help, and that is where the VP9 codec comes in.
The Announcement
At the beginning of this week, YouTube's official blog announced that the video portal will begin encoding content under VP9. In reality, what starts is an acceleration in the adoption of the codec, as YouTube has delivered billions of hours of VP9 video. The two main advantages of VP9 are that it is an open source codec free of royalties, and it manages to preserve the same quality as other competing codecs with half the bandwidth. The official publication makes a comparison between VP9 and H.264 on a 600 kilobits per second connection. While the VP9 video could be described as "standard definition", the H.264 video ranks much lower. YouTube highlights that users most affected by low speeds and buffer interruptions will now be able to raise the video quality one notch, enjoying (for example) 720p video when previously they could only see 480p.
A Dose of Skepticism
Obviously, YouTube's announcement errs on the optimistic side for a few reasons. First, if a 720p video with VP9 consumes half the bandwidth, what YouTube will achieve is to offer 720p video to two users instead of one (thus doubling the amount of advertising), or let a single user access higher quality video, which will keep bandwidth consumption at similar levels. And second, the company does not mention specific bitrates, which is the real concern here. The user's interest is in getting better video quality without pauses or jumps. Codecs are not magic, and when YouTube talks about the "50 percent of the bandwidth", one cannot help but think of some loss. Once 4K streaming does its thing, we will know the truth.
