How to Choose a Video Capture Card
Once all content is edited and ready for output, the majority of the nonlinear editing systems are adequate for output to high-end formats such as DVD MPEG-2 content as well as streaming formats. Apple Compressor, an add-on to Final Cut Pro software, as well as Adobe Media Encoder, which comes bundled with the Adobe Creative Suite, provide dozens of formats and hundreds of settings for customized content delivery formats.
For those who might need an additional tool to do the heavy lifting of converting files from one format to many formats, or to encode complex scenes that are causing the output file to choke on high-bandwidth data spikes, several other tools do the trick, including Sorenson Squeeze, Grass Valley ProCoder, and Autodesk Cleaner. All of these offer three features that make life easier for the content creator: profiles that can be saved and applied to multiple video files; batch processing which allows tens or hundreds of files to be transcoded with no need to manually start encoding each file; and automated watch folders, which automatically begin to apply encoding profiles to any file that appears in a particular folder. Additional tools from Digital Rapids and Inlet, noted above, perform similar functions to Cleaner and contain additional tools to tweak particular parts of a file—rather than having to completely re-encode an entire file—plus include the added benefit of rapid transcoding thanks to hardware accelerators sold by both companies.
In conclusion, the industry continues its shift in two directions. On the standard-definition front, the move is away from add-on video cards and toward software-only solutions that use internal FireWire or USB ports or small outboard capture devices and a power central processing unit (CPU) to perform streaming encoding and delivery chores. While these software-based solutions perform admirably in many circumstances, the pre-processing of video and audio signals provided on capture cards made by NewTek, Digital Rapids, Inlet, ViewCast, and others will ensure a market for those products for at least the next year.
On the high-definition front, software-only solutions are adequate for encoding on-demand content, but will not suffice for capturing high-definition content live and simultaneously streaming it. Even complex hardware solutions are just approaching the ability to transcode content into other high-definition formats or down to standard-definition formats, a trend that will continue throughout 2007 as a significant amount of content begins to be captured in high-definition formats. Software-based high-definition capture is possible for previously compressed video formats such as HDV, which use the same 25Mbps capture rate as their standard-definition MiniDV predecessor (or, for 720-line acquisition, as low as 19Mbps), but this content must be cached first on the capture computer and then transcoded—typically over a time of 2 to 3 times the length of the initial video and at 90-95% CPU load—before being available in bandwidths low enough to be streamed on the internet.