Telestream Wirecast

有一个古老的好莱坞笑话，其中有一句妙语:“但我真的想当导演。." I'm not sure what the actual joke is, 或者它是否有趣, 但我提出这个问题的原因是，如果你和作家交谈, 大多数人会说, "but I really want to be on TV." Certainly the web and websites such as Livestream and Ustream have made that possible to some degree. 但大多数产品都缺乏DVR回放等功能, 活绿屏, and other effects and capabilities. 对所有想当播音员的人，我有一个好消息和一个坏消息.

The good news is that you can get most of the relevant functionality used by your local TV station by purchasing Telestream Wirecast, 它可以在Mac和Windows电脑上运行，售价449美元. 坏消息是? 好吧, judging from my own experience, you may not look as good on camera as you 虽然t, 还有那些可爱的, grubby days of getting to your desk without shaving and/or doing your makeup are definitely over-at least on broadcast days.

作为概述, Telestream Wirecast is a software-only live (or live to disk) video production tool that mixes multiple inputs; adds transitions, 标题, and other effects; and produces a stream that you can have delivered by CDNs such as Limelight and Akamai and live streaming service providers such as Livestream, Ustream, 贾斯汀.tv和WebCast-TV. 配置Wowza Media Server 2 Advanced时, Wirecast can serve multiprotocol streams to the iPhone and the iPod touch; to Flash, Silverlight, and QuickTime web players; and to IPTV set-top boxes.

功能
To put Wirecast's capabilities in perspective, think back to the last newscast that you watched. 新闻广播在演播室的主播和现场的记者之间切换, added 标题 over the video, played canned clips from other sources, and showed a live green-screen shot of the weatherperson (doubtless he or she was predicting more snow and cold for the freakish winter of 2010). 好吧, Wirecast does all of that and more, and you can run it on a Mac or Windows notebook.
具体地说, Wirecast可以接受大多数设备的输入，这些设备可以连接到您的计算机上, 包括网络摄像头, DV /丁肝病毒摄像机, and other cameras via hardware analog inputs. 在我的测试中, which were done primarily on a MacBook Pro, I configured two live feeds, the iSight web cam and a Canon ZR500 Camcorder. I also configured in multiple additional sources that you can see on the shot list contained on the bottom row of 图1.

图1 shows the basic Wirecast interface. On the top right is the "live" stream, 左上角是排队等待下一个出现的流, or the Preview window, 这就解释了屏幕左上角的P了吗. You can switch feeds one of two ways. 如果单击界面底部的自动实时复选框, 只需点击不同的场景切换到它使用配置的过渡, which defaults to a 1-second cross dissolve. 当你既是天才又是运营者时，这种方法会很有效, since it only takes one click to switch.

Or, if you uncheck the check box, click on a scene to load it into the preview window and then press the Go button beneath the live window to switch over, 再一次。, via the selected transition. 如果你是切换到其他演示者的操作员, this is probably the mode you'll use because you can preview the next scene to make sure the configuration is correct before going live.

Wirecast's (Initially Hidden) Layers
从概念上讲, think of Wirecast as having four visual layers, which are shown on the bottom left of 图1. Titles have an obvious function, while the Foreground is for logos and other overlay graphics. Normal is the most used layer. It contains shots such as your live cameras, disk-based content, full-screen graphics, and the like. The Background layer is for backgrounds that appear when foreground elements don't fill the screen. 还有一个音频层，你可以在其中配置来自音频源的输入.

所有的视频层都是单独工作的，你可以在它们之间单独切换. This allows you, 例如, to turn a title on or off without impacting the live video beneath it. To control what's being seen on a certain layer, 点击左边图层的标题来显示可用的内容, and click the shot that you want to include. 例如，在图2中，我选择了Title层.

To make a shot disappear, click the Blank Shot button on the extreme left, 或者划掉预览窗口或实时窗口下面的图层. Though the Jan Title shot in 图2 is selected in the Title panel, 我已经把它划掉了在右边的活动窗口下面, so it's gone from the frame. If I clicked the Foreground layer, you would see a button labeled SMC logo, which contains the StreamingMedia.com logo you see in the frame. To get rid of the logo, 我将单击划掉的Title按钮右边的按钮, 或单击前景拍摄列表中的空白拍摄按钮.
最初使操作复杂化的是一个如此简化的默认视图, it doesn't even show the layers on the lower left. 当然，这是一个Mac程序，所以杂乱是不好的，“少即是多”是今天的原则. 第一步应该是通过菜单命令显示图层. 但是，更改演示文稿仍然需要两次点击, one to access the layer, the next to choose the content. +, you can't see what's in (or more importantly, what's not in) the layer until you click it, which can get awkward. 幸运的是, 您还可以为每个图层打开单独的小窗口, which gets cluttered, but it makes your content much more accessible.

Pulling Together Your Show
The basic working unit for Wirecast is a "shot,它由一个输入组成，可以配置多种方式. 例如，在 图3，我有一个新的镜头，它将在普通图层的镜头列表中结束. 尽管它使用了与图1中左侧所示相同的两个组件, 这是一个不同的观点，我可以在演示过程中切换. So if I have five different slides that I want to show with five different picture-in-picture locations, I set each slide up as a shot using the desired configuration and then switch between them during the presentation.

One of Wirecast's strengths is the diversity of the types of media the product can input and switch to and from 实时地. One example is shown in 图4. It appears that Wirecast overlaid, 实时地, 这是一个基于磁盘的绿屏视频，在演示过程中播放ppt幻灯片. Though I didn't try this with live video, 在该网站上列出的推荐信中，至少有一篇溢于言表, "We love it because of the green screen feature,“所以我认为它已经完成了，而且效果很好.

When queuing disk-based video, 您可以完全控制视频的开始和停止点, which are 再一次。 encapsulated into a single shot. So, 例如, 如果要在演示过程中显示较长剪辑的三个片段, you would set each segment up as a shot and then click the shot during the presentation to display just that segment. You can see the playback controls in 图5, as I queue a segment of Eric Schumacher-Rasmussen's Reader's Choice awards presentation in London last year.

You can also broadcast the screen (or window) of any computer available on the local 网work via a free cross-platform applet called Desktop Presenter. Once you load this applet on the other computer, you can add it to the shot list by choosing Media > New Desktop Presenter. If Apple Bonjour is running on both computers, the host computer should find the other one automatically; if not, 可以手动输入IP地址进行定位, which Telestream simplifies by 虽然tfully listing the IP address on the Desktop Presenter applet running on the remote computer (图6).

桌面演示器可以证明在许多设置中非常有用. 例如, if your presentation involves multiple speakers, you can preconfigure each speaker's notebook before the shoot and then easily switch over during the presentation. In a single-person presentation, you can use one computer for Wirecast and then switch over to another computer to demonstrate an application.

Note that I ran Wirecast on the MacBook Pro and Desktop Presenter on a HP 8710p notebook, 所以似乎没有任何与平台相关的问题.

Note that the current version of Wirecast can also broadcast the screen of the computer running Wirecast, but it's full-screen only. 虽然您可以配置在镜头编辑屏幕中呈现的区域, most users will find it easier to use a different computer linked in via Desktop Presenter to demonstrate an application during the presentation.

不管是什么来源, all scenes are saved in a specific project file, 每次演讲你都要从零开始. 您可以在几个场景中看到这种操作模式. If you're the presenter/operator, you build a sequential list of shots that functions almost like a storyboard-some shots are live shots from one of the cameras, some are canned video, some are full-page graphics, 还有一些是通过桌面演示器访问的计算机屏幕. As you go through the show, you click from shot to shot, which should be simple enough for most users.

如果您是为其他演示者切换多个提要的操作员, you simply set up each camera view in the shot list and switch between them during the show as needed, pretty much like a live hardware switcher. 无论选择哪种模式，其功能都是直接且可访问的.

标志和头衔
当然, 你会想要添加标题和标志到你的镜头, 而Wirecast也让这个问题变得相对简单. The title tool is particularly useful, with a range of highly attractive lower-third templates. They're easy to select and to use; just click a template in the bin and type in the desired text; if you don't like the canned font/color combination, you can easily change it (图7). 令人惊讶的是，没有匹配的全屏标题. 当然, 您可以在任何图像编辑器中轻松创建自己的图像, 但如果能选择与低三分之一匹配的全屏游戏就更好了.

The logo tool was functional, 但不太直观, 需要翻翻手册才能弄清楚如何调整徽标的大小, 一个常用的操作，使用边界框会更容易. 而不是, you have to "Turn off Respect Aspect Ratio and hold the shift-command keys while moving the mouse in the Preview area.“一旦你得到了它, 虽然, 你懂的, and that particular keystroke sequence is used consistently for resizing content throughout the program.

Distributing Your Video
When you start your projects, you should configure your project aspect ratio and resolution and a matching encoding preset (图8). As with most video-related projects, 如果您看到黑条围绕您的视频输入, it's a sign that something isn't matching and you need to adjust either the aspect ratio or the encoding preset.

一旦你准备好了广播，选择一个目的地. If you're producing in the Flash format, you can use an RTMP Flash Server, use multiple service providers, 或记录到磁盘(图9). If producing in the QuickTime format, you can announce to a QuickTime Streaming Server, transmit to a Built-in Streaming Server, produce unicast or multicast streams, 或者记录到磁盘.

测试软件, 我录制了多个演示到磁盘上，然后在Livestream上创建了一个帐户, which took all of about 10 minutes.

Once you're all configured and directed, press the Broadcast icon on the top left of the Wirecast interface to start the broadcast. Livestream的整合工作得很顺利，我在瞬间就向全世界直播了。图10). My first 虽然t was, "Oh, cripes. 我需要刮胡子." Sure hope Mom doesn't see that one.

整体, Wirecast offers an exceptional blend of well-targeted functionality that's unique in the price range, and after you get settled into the interface, it's relatively simple to use. 如果你真的想放弃写作的琐事，把它放到网络电视上, or if you have a real job and just want to create some highly polished live or live-to-disk inter网 broadcasts, Wirecast should be on top of your purchasing list.

Jan Ozer's article first appeared on OnlineVideo.网