The HEVC Holding Pattern: Will '16 Be the Year for H.265年支持?

过去两年了, I’ve presented sessions at the 流媒体 East and West conferences comparing output from the x264 and x265 codecs to evaluate the health and readiness of HEVC/H.265作为下一代视频编解码器. 缓慢而坚定, X265稳步上涨, offering equivalent quality while saving on file sizes and encoding speeds. 我的大部分测试内容, I’ve seen x265 content encode at half the file size (or average bitrate) of x264-processed content. From an encoding point of view, the technology is ready.

然而，我们还远远没有准备好部署HEVC/H.265 content over the internet, because there’s no ubiquitous H.265解码器在桌面或移动浏览器中使用. The Flash haters out there may be loath to admit it, but Flash was the H.264网络视频革命的创可贴.264 playback was not available natively across all browsers. 因为H.264和H.265不是免版税的编解码器, Adobe等公司, 微软, 谷歌, and Apple have paid to use the codec in their products.

But there’s a problem: Adobe has not added HEVC/H.265解码能力到Flash, 而且只有一个浏览器插件, DivX网络播放器, 为H做广告.265解码能力. (Remember: HTML5 does not endorse specific video or audio codecs—it merely provides a mechanism by which to suggest various formats for playback on a given browser.) So we’re left in a holding pattern for web-based 4K video deployment. 超高清(UHD)播放与H.264 is possible over the internet in a web browser, but most content providers aren’t likely to dive into delivering at bitrates that could easily exceed 8Mbps.

In the world of OTT playback, we are starting to see HEVC decoding capabilities built into smart TVs. Everyone from Samsung to LG to Sony wants to maximize UHD content over the internet, and 4K resolution produces much larger file sizes than does 1080p. Any codec that can retain quality while reducing overall bitrate is going to keep the owner of a 4K TV happily viewing Netflix or Amazon content with greatly reduced risk of buffering or stalled playback.

即使管道已经到位, there is still the issue of subjective evaluation of Ultra HD and the best uses of that sharp resolution. I’m not alone in my “over definition” reaction to the hyper-real presentation of fictional narratives presented in Netflix and Amazon 4K series. I have to hand it to make-up artists who can hide their craft in the pore-magnifying close-ups of character’s faces. 刚刚过去的假期, I bought and then returned my first 4K television set for two reasons: LED light bleed emitting from corners of the display, and the unpleasant experience of watching the 4K content available on Netflix and Amazon. 我妻子找到了布景和灯光火星 so stage-like and unreal when viewed with all that extra detail, that I ended up applying “softening” filters from the TV’s effect menu to make the movie appear more atmospheric and cinematic.

到目前为止, the content that I find holds up best to higher resolution viewing experience is documentary or live events, 比如运动, 奖了, 也许还有电视真人秀. There’s less need for suspension of disbelief when you’re not watching fictional characters in soundstage landscapes. It’s hard to imagine how traditional stagecraft will live up to 8K expectations.

现在的问题是——围绕H.265在2016年成为现实? Will we see 微软, 谷歌, and Apple rally around H.265在他们的浏览器支持? Or will Flash be resurrected, once again, if Adobe adds H.265年支持? 只有时间能证明一切.

This article appears in the April/May 2016 issue of 流媒体杂志 作为“HEVC和UHD:我们(不)需要什么”."

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