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Netflix Keeping Bandwidth Usage Low By Encoding Its Video With VP9 and H.264/AVC Codecs (slashgear.com)
Netflix announced last week that it is getting offline video downloads support. The company has since shared that it is using VP9 video compression codec to ensure that the file sizes don't weigh a lot. An anonymous reader shares an article on Slashgear (edited): For streaming content, Netflix largely relies on H.264/AVC to reduce the bandwidth, but for downloading content, it uses VP9 encoding. VP9 can allow better quality videos for the same amount of data needed to download. The challenge is that VP9 isn't supported by all streaming providers -- it is supported on Android devices and via the Chrome browser. So to get around that lack of support on iOS, Netflix is offering downloads in H.264/AVC High whereas streams are encoded in H.264/AVC Main on such devices. Netflix chooses the optimal encoding format for each title on its service after finding, for instance, that animated films are easier to encode than live-action. Netflix says that H.264 High encoding saves 19% bandwidth compared to other encoding standards while VP9 saves 36%.
Nobody wants to pay the licensing fees for it, so it's dead in the water.
I mean the newest devices support it in hardware, but it has to be a very new chip to have H.265 support. The vast majority of devices in use don't. For computers you could do it in software but that isn't ideal, since H.265 decoding is rather heavy so you'd hit the CPU pretty hard, whereas hardware accelerated H.264 would hit it almost not at all. For mobile/embedded devices though it just won't work. Too CPU intensive to do in software, so people need a new device.
Most modern mid-to-high end phones and tablets have hardware h.265 already. See the SnapDragon video specs.
Oh no... it's the future.
It's not just about money, either. The licensing situation for H.265 a cluster-fuck, with patent holders having split into 2 licensing pools and several other patent holders that aren't participating in either pool. So even if companies were content with paying the licensing fees (which are significantly higher than H.264), they don't have any easy way of doing so that will cover all the patent holders. Most big players would prefer to pay and use H.265, but the patent holders have gotten too greedy and too splintered.
Most of the major players have gotten fed up with this shit, and committed to pool their patents and expertise create a royalty free format AV1, in place of H.265. Alliance for Open Media includes: Microsoft, Google, Mozilla, Netfix, Amazon, BBC, ARM, Intel, AMD, nVidia, Broadcom, Cisco, Polycom, and more. The only companies that haven't signed on yet and are big enough to prevent wide adoption are Apple and Qualcomm, and Qualcomm has previously supported VP9, so I don't know why they wouldn't support AV1 once it is ready.
Codecs (such as H.264 or VP9) describe a bit stream, and how to decode the bit stream. They basically provide a kit of tools that can be be used by encoders.
The quality of video encoding is mainly due to the technical knowledge and artistry of the encoder manufacturer and how the use that took kit. I can show you great H.264 encoders and horrible H.264 encoders, but they both emit valid H.264 bit streams.
In particular, the biggest challenge is rate control. If you don't care about the details of a variable bit rate, almost anyone can write a great H.264 or VP9 encoder, with the bit rate jumping up and down all over the place. However if you expect a bit rate to be held within say +/- 100 kbps, only a few vendors have the expertise to make a more constant bit rate look good.
I'll also add that I've seen no good data that shows that VP9 encoders perform better over a wide range of content than H.264.
H.265 would have easily dominated the market already
But it hasn't and it won't. H.265 has no future in web video. AV1 from the Alliance for Open Media is the future of web video. Netflix will use VP9 for now and transition to AV1 when it's ready.