Macs are well-known to be excellent at working with graphics and video and are especially well-suited to live broadcasting due to their overall stability and graphics capabilities. In this tutorial I'll show you how to live-stream an event, using Wirecast on a Mac, and I'll show you some of the hardware, software, and service providers that are needed for a successful live video stream.
The first thing you should consider is how many viewers you'll have and how to distribute the stream to your viewers. If you have 200 people watching and they were to connect directly to your Mac, your internet connection would probably choke and die.
A much better solution is to use a streaming host or CDN (content delivery network—a set of servers tuned to efficiently deliver content to viewers across the globe) to distribute your video feed. Basically, you send one copy of the stream up to the streaming host server, and they handle all 200 viewer connections, ensuring that everyone gets a good quality signal without choking your bandwidth.
If you feel like geeking out and building your own streaming server, you certainly can. But if that's you, you're probably not reading this post anyway! A few user-friendly options include justin.tv, Youtube (if you have at least 100 subscribers to your channel), and Ustream.tv. These three options are ad-supported and have some other limitations for the free version, but offer paid plans without ads, along with other options such as HD, password protection, etc. Sermon.net is another option geared specifically towards churches and houses of worship and is quite affordable.
Hardware really makes a difference; after all, you're asking your computer to resize a live video feed, possibly add overlays and special effects, scale, recompress, and upload—all at the same time without delay. Though you don’t need the latest-and-greatest top-of-the-line equipment, at least a recent mid-range computer would be good. At the very least, you'll need 2GB of RAM, but the more, the better. Your CPU should be at least a 2.0GHz Core 2 Duo, but an i3, i5, i7, or better would be good.
A high-quality audio stream can make jerky video more bearable, but terrible or distant-sounding audio can’t make up for great video quality. If at all possible, use a lapel or headset microphone for a moving source or a good quality mic close to a stationary source.
If you’re in a venue with a soundboard, connecting directly into the soundboard would give you the best audio possible. In this case, take a look at the soundboard to see what output options it has. If you’re lucky enough to have a digital soundboard with digital audio, USB, or Firewire output, by all means use that.
Otherwise, connect your Mac's audio input port to the soundboard using one of the analog options pictured below. An electronics supply store can find any combination of these cables that you may need to connect to your soundboard.
When deciding on a camera, the optics make all the difference. A built-in or add-on webcam could work but likely won’t be very clear, especially if the subject is more than a few feet away. A consumer-grade camera with a Firewire or HDMI output would work; better yet, get a professional camera like the Canon Vixia HV40 or Sony HVR-V1U. If your camera doesn’t provide a USB or Firewire feed, you’ll need a converter box like the Blackmagic Intensity to convert the video feed to a format your computer will handle.
If you want to provide an HD stream, you'll definitely need a professional, or higher specification, camera and a input converter—Firewire just won't handle that much data at once.
Your bandwidth may also be a limiting factor—start with your streaming host’s recommendation for quality settings. Test and tweak the export settings as needed. In general, you'll need at least a high-speed DSL for a small (640x480) framesize. For any HD video, you'll want at least 2MBps upload, and you'll want to keep other people from using it as much as possible during the event.
Now for the fun part. Wirecast is a wonderful piece of software; although it’s somewhat expensive (starts at $495), it’s worth every penny if you’re producing live-streams often. If you want HD video, you can pay $99 more; Wirecast Pro also provides 3D virtual sets, scoreboards, and more, for $995.
“What makes it so good?” Glad you asked!
It can handle a number of live audio and video sources:
- Multiple cameras and audio sources
- Live shots of another computer’s desktops (great for slideshows and Skype calls)
- Pre-recorded audio/video files
- And much more!
Wirecast can also add motion and still title overlays on top of live video and let you edit the live stream on the fly with a number of color correction filters and other effects. If you don’t like any of the the built-in overlays, you can build your own with image editing software and import them as photos.
In addition to all the input, overlay, and editing features, Wirecast comes with a dizzying array of encoder presets, covering a range of video frame sizes, bitrates, and other options. You can send the audio/video stream to a number of streaming hosts any of the presets, or customize to fit your exact needs. Some streaming hosts use Flash-formatted video and some use H.264, which is more friendly for mobile devices. Others accept Flash and transcosde it to H.264 on-the-fly for mobile devices.
More than just providing a live stream, Wirecast can record the entire event straight to your hard drive as a MPEG-4 or Flash video file, for easy archival or post-production work. (Note: you'll want to record in the same format that you stream or you'll double the workload on your computer.)
When setting up Wirecast for the first time, try some of the built-in encoder presets. If possible, watch the stream on several different devices to see how it looks both large and small; check it in a range of settings from full-screen on a large desktop monitor to a mobile device. Then tweak the encoder settings a bit to fit your needs.
Keep in mind that every additional output may require a lot of processing horsepower, so you don’t want to get too crazy with options. However, it is nice to provide the option of a high- and low-bandwidth stream, and some “viewers” like an audio-only stream, especially if they’re watching on a smartphone with a limited data plan.
During the event
In my opinion, it’s nice to have a intro slide and background music broadcasting at least 5 minutes before the live event to give people a time buffer to tune in, rather than trying to start the stream exactly when you start broadcasting.
Event intro slide
During your live event, keep an eye on the audio meter to make sure that your audience can hear. If possible, tune in to the livestream on another device to check the audio and video quality.
In this tutorial, I looked at a lot information about live-streaming: how to distribute the final stream, how to get the video and audio feeds into your Mac, and how Wirecast can handle the video. As you can see, Wirecast is a powerful program with plenty of features to help you produce a high-quality, interesting live-stream. If this has whet your appetite to try live-streaming, leave your thoughts, tips and questions in the comments below.