Getting started with streaming media

Streaming media is the talk of the town - at NAB, in the news and on the Internet. There have been debates over whether streaming media will take over
Author:
Publish date:

Streaming media is the talk of the town - at NAB, in the news and on the Internet. There have been debates over whether streaming media will take over the television broadcast world. Most agree that it will be a long time coming. But it is also assumed that streaming media will be an integral part of content delivery and that it will see phenomenal growth over the next few years.

The question for content producers and broadcasters is how to follow the trend and stay ahead of the technology curve in this evolving industry.

The basic steps to delivering streaming media to your audience are as follows: produce, capture, encode, serve. Each of these steps requires a set of skills and technology applications based on where, how and when you are going to stream your content.

Producing content for the Web Professional broadcasting has a lot going for it in terms of producing or repurposing content for streaming delivery. Although today's modem users see small, low-quality images over the Internet, it is still important to start the production process with the highest-quality video and audio you can afford. As broadband delivery becomes more prevalent, the competition will heat up in terms of delivering the highest-quality productions. The good news is that MPEG-2, the standard for digital television, is a suitable format for beginning the media production process.

Broadcasters should also keep in mind that streaming media is not limited to video and audio content. When integrated into a webpage, these media elements can be combined with textual information, interactive elements and graphic overlays. Your production tools will need to include more applications to produce these immersive websites for your viewers.

One mindset that may need adjusting is the way motion graphics and effects are applied to your content. In fact, many producers may take straight video and audio and redo effects with more efficient technologies for delivery over the limited pipes of today's networks. These might include Flash and client-side rendering effects that can be accomplished in QuickTime.

With these thoughts in mind, you can produce a television show back to tape and move on to the capture phase of the production. Or you can keep these elements in mind as you produce a live show and webcast directly to your Internet audience as well.

Capturing and encoding content for streaming Generally speaking, video and audio capture and encoding are accomplished on a dedicated workstation or bank of encoders, depending on your delivery formats. If you are streaming live, this is a one-step process. For video-on-demand (VOD) applications, you can achieve better quality by capturing at very high resolution and then transcoding to the compressed formats for delivery over your network.

Input to the capture process can be analog or digital, composite or component, over firewire or SDI. It all depends on your budget and choice of capture cards and systems. Look for an upcoming article for more information on the latest technology in this field. We'll also discuss some pre-production issues you need to consider in the coming year.

Encoding is the process of compressing video and audio content and then packaging these streams for serving over a network. There are three major formats for delivery today: Apple's QuickTime, Real Network's RealSystem and Microsoft's Windows Media Technologies. These technologies include an underlying architecture used to produce content, a format description and server applications for delivery over networks.

Your choice of a format and data rates for delivery boils down to your target audience and the scope of your enterprise. Modem users can receive streaming media at data rates up to 53Kb/s. Broadband connections vary from 128Kb/s to 1.5Mb/s and above. A sample of connection speeds and technologies is given in Table 1. All of the delivery formats are designed to deliver across the entire range of network bandwidths.

Encoding is a time-consuming, CPU intensive operation. There are systems today capable of encoding four to six simultaneous streams. In addition, each of the delivery formats have methods for packaging different bit rates into one stream for more efficient delivery. If you choose to encode your content, expect a large capital outlay.

Another option for encoding is to rely on the multitude of streaming media service providers in existence. Most will accept taped content and satellite feeds, as well as MPEG-2 transport streams for live or VOD encoding and delivery. (See "Streaming" in BE's June 2000 issue for coverage of these providers.) If you are encoding live you might also want to consider archiving the material for viewing on demand. In addition to encoding, these service providers will also have the capabilities or partnerships in place to serve your content.

Serving your streaming media Today's streaming media can be delivered using several different methods. True streaming media requires a specialized server such as RealServer, WindowsMedia Server or the QuickTime Streaming Server (QTSS). Your content is then delivered and viewed in real time, whether it originates from a live event or an archived media file. The caveat to true streaming is that the bit rate of the movie must match the bandwidth of the connection or buffering will occur and playback will be interrupted.

Without the specialized server application residing on a web server, media can be delivered by using progressive download. This is sometimes referred to as HTTP streaming because the media is delivered from a basic HTTP server - any server set up to deliver webpages as well. HTTP serving is designed to be an error-free delivery process using error correction mechanisms that will retransmit lost data. This process is not conducive to streaming media because it interrupts the playback of such files on the client's computer. With many simultaneous clients, this can also drain the resources of the server.

Longer programs are more conducive to true streaming, since then they are not saved on the client's computer. There will be a short delay on the client side as the streaming server buffers the content. On steady network connections, no further interruptions will occur during the delivery.

The number of simultaneous streams you wish to serve is a function of your total network capacity and your server capacity. Aggregate bandwidth adds up quickly, and infrastructure for a large network is costly. Again, many service providers are ramping up their networks for streaming media delivery and it may be in broadcasters' best interest to seek out these providers. This aspect of the industry will be covered in a later issue as well.

Converging on your target audience Today, streaming media is primarily viewed on computers using standard browser applications, so the audience is still limited. Broadband delivery via cable modems and DSL is building out, but to reach more eyes and ears many providers are keeping the modem user in mind when they produce and serve their content.

The industry is still building the infrastructure to deliver much more content at higher connection speeds for increased quality and business revenue sources. Convergence may come in other flavors as well. There have been experiments with interactive television and developments for viewing websites on a television in the past. Datacasting, or using some of the television broadcast spectrum for digital data, is another delivery mechanism that may take off as digital transmission standards are implemented around the world.

No matter how it is delivered, once the technology is in place it will be the content producers - the broadcasters - who will benefit from these increased markets and new applications. Stay tuned for further details on how you can begin the process of implementing streaming media in your productions and facilities.