2010年12月31日
By 1月时特约编辑
专题文章

流媒体焦点:彼得·斯科特，特纳体育

Every year or so I have a chance to talk tech with Peter Scott, 谁, 特纳体育新兴媒体副总裁, oversees digital operations 和 technology for 特纳's current portfolio which includes TNT加班在NBA.com, TNT RaceBuddy, 和 PGA锦标赛生活. As a journalist 和 consultant, I live in a bit of a theoretical glass tower. 与此形成鲜明对比的是, 彼得住在马路与橡胶相遇的地方, delivering streams to customers that advertisers have to pay for. I value his experience, perspective 和 knowledge, 和 appreciate the opportunity to chat. 以下是我们今年的报道.

流媒体:跟我说说今年的PGA锦标赛吧.

彼得·斯科特: 有趣的比赛，特纳取得了巨大的成功. 提供一些观点, 去年我们向台式机提供了两种流媒体, 一个是通过Flash, the other a higher quality (HQ) stream that required the viewers to download a plug-in, 并且稍微延迟了. 去年, 70-80%的观众观看了Flash流, 我们在640x360@800 KBPS配置的, 20 - 30%的人选择了总部流, 也就是2.2 mbps. We felt that the plug-in 和 delay presented a barrier that dissuaded many potential viewers from the higher quality, 我们想鼓励的是什么.

所以今年, 我们切换到Akamai HTTP HD Network播放器, 以从500 KBPS到2的六种不同比特率进行编码.5mbps，并自适应传输流. 除了Flash之外，不需要任何插件, 当然, 事实上，所有的观众都有这种感觉, 我们发现75%的观众使用1连接.5mbps高清流. Because it was delivered via HTTP, there were also no firewall issues.

流媒体: What did you do to complement the higher quality video?

几件事情. 首先，我们在智能DVR中展示了视频. 当观众连接时, 他们看了直播, 但是可以向后滚动, with markers at significant events in the stream (see figure). 我们在现场有一个记录器，通过XML记录这些时刻. 观众可以将鼠标悬停在各种标记上, 看看那个地方发生了什么, 点击重播视频. Viewers liked that feature, with over 40% clicking back at one time or another.

Ozer 特纳图1

特纳's Smart DVR, with markers at key events, scorecards, leaderboards 和 fan chat.

我们还添加了一个排行榜，观众可以在屏幕上显示, 记分卡和聊天, 我们再次发现很多人参与了这些特征. Overall, traffic numbers were off the charts, 和 the bitrate average is 1.5 kbps.

流媒体:成本是多少?

好吧, that's the downside, served a lot more bits through our CDNs 和 had to pay more. Balancing that was a great user experience, which we were able to monetize with advertising. Our advertisers loved the quality of the experience 和 the extensive viewer exposure.

流媒体: You seem pretty bullish on HTTP-bases streaming; why is that?

根据我们的经验, HTTP在提供视频服务方面比RTMP更有效, 和 we feel that we've mastered the ability to deliver in HTTP. HTTP允许我们以块的形式提供视频, which we can manage more efficiently than sending one or more continuous high bitrate streams. We also think it's more efficient on the infrastructure side due to caching, 并且完全避免了防火墙的问题.

流媒体: What about Zeri (Adobe's HTTP-based streaming technology)?

好吧, because of the nature of some of our episodic projects - think PGA锦标赛, or March Madness - we can try new technologies 和 see how they work. We had a great experience with Akamai, but if Zeri is available 和 proven by March, we may try it.

最终由观众决定. 作为出版商, we can test different technologies to see which delivers the most feature rich, 具有成本效益的流, but the user experience is paramount to our viewers 和 advertisers. All that said, we had a great experience with Akamai's technology, 和 now it's proven.

(For more on adaptive streaming technologies in practice, see "自适应流在现场.")

流媒体:你们是如何为ipad服务的?

All of our sites—whether it's the NBA, PGA or NASCAR—all support iDevices. Our web site detects the device 和 uses Apple's HTTP 在线直播 to adaptively deliver the appropriate stream.

From a technical perspective, we encode these inhouse 和 upload them to Akamai for delivery. 我们编码了四种不同的流，范围为1.iPad的速度是2mbps，我们看到了很多基于iPad的流量.

流媒体: What's your sense of whether you were competing against the television broadcast or enhancing it?

有趣的问题. I think your strategy there depends upon whether your typical viewer has access to a live TV feed or not. 如果不是, a high quality adaptive bitrate stream can be very effective, 即使有二三十秒的延迟.

与此形成鲜明对比的是, 如果观众可以在电视上观看的话, 他们当然可以在PGA锦标赛上做到这一点, you have to attach relevance 和 personalization to complement HD/HQ experience. Clearly, TV can't personalize the experience, which viewers seem to really appreciate. 例如, one huge turning point in the PGA锦标赛 was when Dustin Johnson grounded his club in the bunker on 18, 但当时没有人意识到这一点. 一旦它变得明显, you had to depend on the network to replay those streams - but our viewers could click the marker 和 see it as many times as they wanted.

The other thing TV can't do is monitor what the viewer is doing, 和 our log files give us instant feedback as to what features the viewers appreciate 和 use. 你马上就知道什么可行，什么不可行, 和 can quickly iterate players 和 make them more interesting. That's a huge benefit that allows you to serve the viewer - 和 ultimately your advertisers - more effectively.

流媒体:特纳对HTML5做了什么?

让我们面对现实吧:这个世界, 特纳包括, 支持Flash，因为它很简单, 但最终, we think Steve Jobs has a point—HTML5 is more accessible in the long term. Right after the introduction of the iPad, we started encoding all videos to H.264格式，这样我们就可以将相同的流传输到Flash, iDevices 和 other HTM5-compatible browsers that support HTHL5. Obviously, we're not ab和oning Flash, but we're monitoring the situation closely.