A Buyer's Guide to Nonlinear Editors

Everyone knows the second one, and it's part of the legacy that brought us online interactive content as well as more recent online video distribution. But you may not be as familiar with DASH, the new MPEG standard for dynamic adaptive streaming over HTTP. DASH is designed to allow content owners to deliver streaming content across a standard web server (HTTP) in multiple bitrates and resolutions, with the best resolution delivered dynamically based on the native screen resolution of the client device as well as currently available bandwidth.

The reason these two streaming delivery options enter into our NLE discussion is that the output formats often determine a large part of the workflow, which itself determines the proper tool. Just as we used to decide on an NLE based on whether it could generate output to a particular broadcast tape format, we also now need to determine whether the NLE and its suite-mates are able to output content in the proper formats.

DASH has an equivalent in three other formats: Apple's HTTP Live Streaming (HLS), Adobe HTTP Dynamic Streaming (HDS), and Microsoft Smooth Streaming. HLS uses MPEG-2 Transport Stream (M2TS), but all the others use a newer technology called fragmented MP4 (FMP4). M2TS requires that audio and video be multiplexed together, where FMP4 allows different audio and video files to be simultaneously segmented at the time of streaming -- allowing for one video stream to be delivered with any number of discrete audio streams -- lowering the overall bitrate required to deliver to any given user.

All rely on an MP4 elementary stream (audio or video or a combination of both) that can be segmented -- or fragmented, or chunked, or a few other names -- into small 2-10-second pieces at a number of bitrates. Until recently, HLS required this segmentation beforehand, resulting in a massive number of small files stored at the HTTP server ahead of time. The most recent draft specification of HLS, which we cover in "The State of Protocols," allows the MP4 files to remain intact, and segmentation occurs just before they are streamed.

Going back to the direct "DASH or Flash?" question, the good news is that prototype versions of the Flash Player have demonstrated DASH integration. The question isn't completely moot, however, as the use of RTMP or RTSP rather than HTTP still requires a dedicated streaming server for delivery.

I Can't Hear You!

One final area to consider is the audio capabilities of your chosen NLE. Those of us who cut our teeth on Pro Tools or other digital audio workstations may have no trouble handling multichannel audio software, but given the fact that we can now deliver surround sound (5.1 or 7.1) as part of a streaming video, the need for multichannel audio capabilities -- including spatial positioning -- should no longer fall on deaf ears when it comes to NLE software manufacturers.

Unfortunately, the average NLE lacks robust audio capabilities, so listen as well as watch when it comes to choosing the best NLE tool for your project. Some NLEs began life as -- or spun off from -- audio software, and their native audio capabilities are likely to be stronger than others as a result. Alternatively, consider choosing an NLE that ships en suite with a dedicated audio tool if you need more sophisticated audio features.

Conclusion

We've barely scratched the surface of NLEs, let alone the multiple layers of compositing or visual effects tools that are offered alongside today's NLE products. Remember to think through these decision points, but also consider the types of input formats (and subsequent requirements to transcode to a "native" NLE video format when considering which tool to use.

Above all, remember that workflows are the most critical aspect of choosing an NLE. Don't be afraid to try out a number of trial versions of tools, including robust asset management and pre-edit logging tools, before you settle on just one. After all, a toolbox is only as good as the wide variety of tools you store in it!

Five Key Questions to Ask When Choosing an Editing Solution or Suite

• Will you edit on a desktop? On a laptop? In a studio? Or in the field?
• Will you be doing a significant amount of compositing or applying multiple layers of video or effects?
• Will your project be edited locally or on a network? Will your project involve collaborative editing in the cloud?
• Which streaming formats will matter most in your outputs?
• Do you need sophisticated pro audio features for editing or sweetening your projects?