A Buyer's Guide to Video Production Switchers
Spend a little or spend a lot -- there's a tremendous price range -- but be sure to ask these questions before you buy a production switcher.
The video production switcher is operated by a technical director who selects or mixes a program output from the available video inputs. Switcher hardware ranges considerably from inexpensive two-input models that lack any features other than a two-button video input selector to large studio consoles that cost more than a Porsche 911.
The video quality from the previous generation of analog video switchers varied greatly, but the current breed of digital video mixers theoretically output an identical video signal as the input signal when effects or mixing aren't used.
So what features are important for a video switcher purchased for use in a streaming video workflow?
All-in-one hardware solutions integrate the control panel and the video switcher while others separate the two components. The video switcher component is housed in either a rackmount case or in a computer, and the control panel can either be a software computer interface or a hardware control panel. The two components are connected, typically by an Ethernet cable.
All-in-one hardware solutions are more portable than individual components, but this also means that all of the cables converge on the video switcher and aren't easily concealed, and the footprint on the tech table can be much larger.
Input Types and Number
HD-SDI is the gold standard for video switcher input connectors because this single cable can run longer than the equivalent consumer HDMI standard and requires one-third as many cables as the analog component video standard. HD-SDI cable, otherwise known as BNC cable, has a bayonet connector and locks securely while the other standards easily can be pulled out accidentally.
Consumer cameras often lack HD-SDI outputs and computers use HDMI, DVI, DisplayPort, or VGA, so having a native computer input on the video switcher is a consideration. Alternatively, a video converter can be used to convert and/or scale a video camera or computer signal to a compliant video switcher input.
When you're choosing a switcher you should also consider the number of video inputs by type and total active inputs. Some video switcher models have more than one available connector type for a given single input, so the number of effective video inputs can be lower than the number of available input connectors.
Output Types and Number
In order to preview each video input, a switcher needs to have a preview output for each video input or a multiview output. While HD-SDI might be the gold standard for running cable on the video input side, HDMI for the preview monitors is widely used, largely because of the cost and availability of large HDTVs and computer monitors that have HDMI inputs. In addition to preview or multi-view outputs, the webcast encoder needs to have a program output unless the video switcher is housed in a computer.
Some video switchers offer additional outputs for SD outputs on an HD switcher, as well as auxiliary outputs that can be programmed to duplicate any of the inputs, the preview, the program output, or additional program outputs for archive recording.
Some video switchers have built-in, full-fledged audio mixing consoles with multiple audio inputs. Others allow a pair of audio inputs from a soundboard or single source, while others don't even pass on embedded HDMI or HD-SDI audio and require the use of an external audio soundboard.
Now featuring a new interview from NAB 2013 on the Sound Devices Pix240i, this article looks at a handful of portable and rackmount external video recorders for live HD production, specifically in the role of recording the master program feed from a live switch.