Buyer's Guide: 在线直播 Services

So, you've decided to stream a live event, and you're considering your options. You definitely need a streaming server to reach your target viewers. You could buy and install your own server (or rent a cloud instance), 但你必须自己创建播放器，配置和管理服务器, which requires lots of technical expertise that you may or may not have. Or, you can use a service provider to supply this functionality.

There are multiple classes of service providers that can get the job done. 例如, if you're currently using an online video platform (OVP), it's likely that it has support for live streaming (or soon will). 如果是这样的话, 你可以使用播放器和你为你的点播视频和现有的分析创建的所有其他功能, 你的实时事件被转换成点播流，并在事件发生后立即添加到你的库中. This level of convenience is tough to beat.

如果你没有OVP, 另一类被称为流媒体直播的服务可能是最好的选择. You can start streaming live at no cost, with various trade-offs in terms of resolution (HD or SD), 第三方广告, 品牌, and scalability that vary among the service providers. As your live streaming activities flourish, 您可以选择不同级别的服务，以消除这些限制，并提供对安全性的更多控制, 货币化, 和品牌. Since 大多数 of these services, which include popular sites such as 转播画面, Ustream, 贾斯汀.tv, 还有最近的YouTube, are popular sites with many viewers looking for content, 如果你只在自己的网站上展示视频，这些网站可能也会提供一些你无法接触到的观众.

Though 大多数 of these companies are only about 6 years old, 这个市场相当成熟, and you'll find more similarities than disparities among the contenders. 例如, they all work similarly. You use a live encoder to send a stream (or streams) to the service provider, who displays the video on a dedicated page in the service, which I'll call the channel page. Depending upon the vendor and the plan you've selected, you may also be able to embed the live stream into a page on your own website. 事后, you can usually trim frames from the start or finish (if necessary), 创建了, and download the video so you can deploy it elsewhere. 您还可以查看观看分析，以查看有多少观众收看和收看了多长时间.

到这里为止, 大多数 services are very social media-aware, with easy links so viewers can tweet and like and otherwise spread the word. They also recognize that viewer interactivity is key, so 大多数 enable comments and chat to some degree. 否则，在所有这些相似之处，您如何为您的现场活动选择最好的服务? 通过关注这里确定的主题，从您最想从服务中得到什么开始.

寻找眼球?

如果你想吸引眼球，你肯定想知道哪些网站流量最大. According to Compete (using November 2013 data), among the non-YouTube participants in the group, 转播画面 has the 大多数 traffic, though there is one potentially significant asterisk. 具体地说, Twitch, a 贾斯汀.tv sister-site dedicated to live gamers, recorded about 2.23 million unique visitors in November 2013, though unless you're attempting to reach these gamers, it's not relevant from an eyeballs perspective.

然而, it is relevant from a scale perspective, meaning that the combined viewership from Twitch and 贾斯汀.tv is the largest (non-YouTube) of the group, 因此，合并后的实体应该有更低的交付成本和更多的用户来分摊开发成本. I'll also point out that according to comScore statistics 贾斯汀.(但我无法从comScore独立证实这一点).tv had more viewers than both 转播画面 and Ustream, 在每个观看者的分钟数和每个观看者的视频数等指标上，收视率也要高得多.

当然, 如果这些网站吸引的浏览者不太可能是你的内容的理想浏览者，那么这些数字都无关紧要. 如果你的目标是吸引眼球, 最好花点时间看看网站上现有的内容，评估现有的浏览者是否适合浏览你的内容.

YouTube怎么样?? 好吧, YouTube is obviously the largest, but that's combined on-demand video and live, and we know the former dwarfs the latter at this stage, which might make your live content harder to find. 这将在后面讨论, 从直播的角度来看，YouTube也缺少一些重要的功能. Just because it's the largest, that doesn't mean it's the best.

White Label: How White and at What Price Level?

除了YouTube之外，所有的直播服务提供商都提供没有服务品牌的“白标签”版本. The question is, how much does it cost to lose the label? 例如, 通过转播画面和Ustream, you have to commit to the $999 plan to remove the respective company's 品牌. 贾斯汀.tv's plan costs $399, while Stockholm's Bambuser 每月599美元.

Beyond removing the service's 品牌, you may also want the ability to add your own 品牌, 其中可能包括选择播放器的背景颜色、在页面上添加徽标或在视频上添加bug等选项. 同样的道理, 你可能还想禁用频道页面(这样观众只能观看你网站上的嵌入式播放器), password-protect or restrict the embedding of your videos, or even geo-block viewers in some geographic locations. Not all services offer these features, so get them on the table early if they're important to your intended use.

Which Site Delivers the Best User Experience?

This one is definitely subjective and content-specific, and there are two extremes: one represented by 转播画面, 另一个是Ustream. 具体地说, 转播画面 presents each event on a separate page, with extensive live blogging capabilities to add videos, 图片, and comments to the experience. 当你试图呈现一个完整的体验而不是简单的直播时，这是很好的.

另一个极端的例子是Ustream，它也被大多数其他服务所使用. 在这个范例中, 每个发布者都有一个单独的页面，在该页面上的窗口中显示实时视频(或以前的实时视频)，并有一个定义的聊天区域, usually to the right of the video. Surrounding the live video are other videos from the same publisher, which is a great way to retain a viewer once you have them on your page.

When researching the various options, 访问所有候选服务上的一些现场活动，并评估每个服务的通道页面. Though this is my subjective opinion, 在一般情况下, 转播画面 optimizes the event, perhaps at the expense of the channel page, 而其他服务优化了事件库，但没有为每个事件提供丰富的体验.

当然, if your goal is to embed the video on your own website and attract viewers there, you care more about the embedded player than the channel page. While 大多数 services deliver roughly the same experience in both places, YouTube Live则不然, 特别是不允许你在自己的网站中嵌入带有评论或其他内容播放列表的播放器. 如果你想在自己的网站上吸引和留住浏览者，这肯定是消极的.

Looking to Mo网ize Your Video?

There are multiple ways to mo网ize your video, 包括插入预-, 在播放中或播放后插入广告，或收取按次付费或订阅费. Services differ significantly here, so if you have a 货币化 model in mind, check early to ensure that your candidate services support it. If you plan to push viewers to your own website, 确保盈利模式既适用于嵌入页面，也适用于服务本身的渠道页面.

Looking to Maximize Your Video?

Most producers are truly live only a few hours a week, 但是有些服务, 比如Ustream, allow you to create a continuous channel feel with their Live Playlists feature. Ustream also allows you to upload videos to your Ustream channel, 填满你的频道, and to syndicate your live content to YouTube, 最大化你的眼球. 虽然你可以从其他服务下载视频并上传到YouTube或其他地方, Ustream's integration saves a couple of time-consuming steps.

Where Do You Want the Video to Play?

这是一个大问题. 此时此刻, 大多数 corporate video producers want their videos to play on computers, as well as iOS and Android mobile devices. 评估服务时, make sure both the channel page and the embedded page plays on all these devices, and note whether your viewers will have to download and app to make this happen.

If you're streaming to consumers, OTT and similar platforms are a plus. 在这里, 转播画面 plays on Roku devices, while Ustream has apps for smart TVs from Samsung and other vendors. Beyond embedding in your own website, 你也可能希望视频在Facebook或Twitter等环境中播放, which not all services support.

寻找免费服务?

If you're looking for a free service, 确保您了解每个供应商对其服务所做的不同权衡. 与Ustream, 例如, the free service is advertising-supported and has a limit of 480p SD video, while Bambuser limits its free service to 50 viewing hours a month. 与此形成鲜明对比的是, 转播画面 goes in a completely different direction, requiring viewers of free content to log in with their free 转播画面 accounts. There are never any advertisements, restrictions on video quality, or viewing limits on 转播画面, 但如果你担心你的观众可能不想注册一个转播画面账户, this may be a significant limitation.

你的预算很紧吗?

The unique curse of streaming video is that if your live event truly goes viral, 它可能会倾家荡产, leaving you with a huge invoice for additional viewing hours and no means to pay. 在这方面, it's significant to note that all 转播画面 plans are totally inclusive; the various plans are differentiated with features, 不考虑观看时间, and there are never any overages. 与此形成鲜明对比的是, 实际上，所有其他服务都将其收费计划与功能和观看时间限制区分开来, with overages when you exceed the plan limits. 当然，关键的例外是YouTube Live，使用它你永远不会产生任何费用.

Are You Broadcasting Out of Tight Spaces?

到这里为止, 大多数, 但并非全部, services support adaptive streaming, 在哪里为观众提供多个流以匹配他们的播放平台和连接速度. 这是一个非常理想的功能，特别是在向移动观众传递信息时. 然而, one major difference is how the service produces these streams.

贾斯汀.tv, Ustream, 和YouTube Live都可以将传入的高质量流转码为多个文件, 减少现场活动的出站带宽需求并简化现场编码. 与此形成鲜明对比的是, 转播画面 producers must encode all streams at the event, 这意味着您需要一个足够强大的编码器来生成流，并需要足够的出站带宽来将流从现场事件位置传输到服务.

Walled Garden or Open Toolset?

All live streams start with an encoder. Most services offer a browser-based encoder, which typically uses the encoder in the Adobe Flash Player, which is easy to use but produces inferior results. Many services also offer their own free desktop encoder, 比如转播画面, 或免费, limited-feature versions of Telestream Wirecast (Ustream, YouTube), which simplify connecting the encoder to the service. 相比之下，犹斯丁.tv doesn't offer its own encoder, which makes getting started a touch more complicated, though not rocket science by any means. There are also several free live encoders available, including Adobe's Flash Media Live Encoder (FMLE), 所以贾斯汀.tv's approach won't cost you any more.

除了这些免费工具, 转播画面 has created its own mixer/encoder program (转播画面 Studio), and on-camera encoder (转播画面 Broadcaster), and a plug-in for the NewTek TriCaster, while refusing to extend support to tools such as Wirecast and FMLE. This has created somewhat of a walled garden around 转播画面 service. According to company officials, 转播画面 pursued this strategy to simplify integration with the service, 并确保他们的技术支持人员能够在编码阶段有效地支持他们的生产者. 当然, 如果Wirecast, FMLE or a similarly unsupported tool is your encoder of choice, 你运气不好.

Ustream has taken a different tack, 提供免费的, 紧密集成的桌面编码器，并追求与其他工具的紧密集成, which is similar to the approach taken by YouTube, 而其他服务, 比如Bambuser和贾斯汀.tv, should work well with any encoder. While on the subject of encoders, if you think you'll be broadcasting from tablets and smartphones, be sure to check if your candidate services supply these encoders.

When Does Live Support Start?

When things go wrong with a live event, you have a short time to get things right, which makes telephone support essential. 没有任何服务为其免费服务提供免费的支持，但它取决于哪些计划获得免费服务. 比如犹斯丁.tv's phone support kicks in with its entry-level $39-per-month plan, and Ustream's phone support starts with its $99-per-month Silver service. 与此形成鲜明对比的是, you'll have to choose 转播画面's Premium service, 每月399美元, 电话支持, and Bambuser's standard service ($329 per month). 此时此刻, there's no mention of phone support in the YouTube Live help offering, which may be the single largest disadvantage of YouTube Live.

本文发表在 2014 流媒体源手册.

Jan Ozer's article first appeared on OnlineVideo.网