In Uncategorizedby tfwm

TFWM’s video editor Jay Delp helps you smoothly sail through the potentially rough waters of understanding switchers and scalers.

Today we have an increasing number of technologies generating or “feeding” the mostly-digital visual content of our ministries. Currently, the top three suspects, in no particular order, include 1) DVD players, 2) video cameras, and 3) computers (both laptop and desktop varieties). Additional technologies include dedicated media presentation systems, portable media players (think video iPods), and the 1,271 VHS players that are still in use within North America. Ok, perhaps a FEW more remain. Just make sure YOUR ministry isn’t contributing to the count.

As ministries of all sizes continue to grow in their desire and ability to incorporate media into their worship services, special events and video productions, the need for finding an adequate (and affordable!) solution for seamlessly integrating this visual content being “fed” from all of these sources becomes priority #1. Enter the video switcher and video scaler. Specifically designed for (hopefully!) seamless selection and switching between multiple video sources, and signal types, today’s video switcher and scalers provide solutions for just about any media ministry regardless of its sophistication, complexity, or lack thereof. Understanding the basic differences between video switchers and video scalers then determining how you can “seek and find” the solution right for you and your ministry (read: budget) is the focus of this article.

At the outset it is vital to understand the primary, not-so-trivial, difference between the basic natures of video switchers (also referred to as video mixers) vs. video scalers. A video switcher is designed for inputting and outputting video sources (composite, S-Video, DV, component, etc.). Video scalers are designed for inputting both video and computer (RGB/VGA, etc.) signals while outputting (usually) 15-pin RBG, in a variety of native resolutions.

I want to note that this basic difference primarily applies to the current low-to-midrange ($500-$5,000) switcher/scaler market. Higher priced (but getting cheaper) true two-in-one switcher/scalers eliminate this primary distinction by providing both types of input and outputs (video and RGB). An example of such a unit will be identified later in this article.

Although a computer can output different video signal types (DVI, RGB, etc.) for purposes of clarity in this article I will simply refer to PC-generated video as “RGB”. In order to process a computer-generated video signal using a video mixer, the RGB signal must first be converted to a video signal. This process is known as “down-scaling” or “down converting” since the superior quality (higher resolution) computer signal is dropped down to the lower resolution video signal. This is most commonly accomplished with components unsurprisingly termed “scan converters” which are available with a wide array of feature lists, resolutions and price tags.

As is true when preparing for any technology purchase, when it comes to scan converters, a little research goes a long way. The short story is-you get what you pay for in terms of features, ease of use and picture quality.

A video scaler, on the other hand, performs the reverse, “up-scaling” video signals to a user selectable output resolution (VGA, SVGA, XGA, etc.). Scalers maintain the pristine quality of computer-generated images (PowerPoint, MediaShout, Easy Worship,etc.) in all their native resolution glory resulting in dramatically improved image color and clarity in the projected output.

Let’s take a look at a few general features and functions of video switchers vs. scalers, the strengths and limitations of each and, how you can decide which is right for you.

There are basically two types of video switchers: frame sync and genlock. Both provide “glitch-free” selection and transition between multiple video sources. A frame sync switcher accomplished this through built-in technology, usually in the form of internal time-base correctors or proprietary digital frame sync circuitry. Genlock switchers accomplish seamless switching by “locking” video signals to an external sync source such as a black burst generator with each signal source (cameras, playback units, etc.) needing connection to (locking to) the same black burst signal. Higher end industrial and broadcast grade cameras include a genlock connection (usually BNC type) for just this purpose. Generally genlock switchers are more expensive (and require a more complex setup) than their frame sync counterparts.

Examples of frame sync switchers include Panasonics 8-input component MX-70 switcher (www.panasonic.com), Newtek’s VT4 (www.newtek.com), Edirol’s 4-input V-4 and 8-input V-440 HD (www.edirol.com), and Panasonic’s line of AVE switchers such as the AVE-5, AVE-7, AVE-55 (www.panasonic.com), and the 4-input Datavideo SE-800AV (www.datavideo.us).

Examples of genlock switchers include all video switchers from Grass Valley, the grand-daddy of genlock switchers, including their Indigo video switcher (www.grassvalley.com).
Unlike scalers, many video switchers include a “T-bar” allowing users to manually dissolve/transition between sources or even pause indefinitely mid-transition. Switchers generally have superior “keying” features for superimposing text and graphics over another video source, most commonly “live” camera images or graphic backgrounds (static or moving) used during worship. These two capabilities combine to provide a more “hands-on”, adaptive and creative aspect of seamless integration of media.

Although there is a wide price range among video switchers and switchers, generally, video switchers are more common in the ultra-tight budget range ($500-$1,000). This is especially true in the pre-owned market (think eBay.com).
Although not a primary consideration, it should be noted that using a video switcher as opposed to a video scaler will result in $ savings for cable runs since VGA cable is more expensive than composite video cable. The use of component or S-video cable with the video switcher will diminish or eliminate this price difference. Obviously, you want to output the highest picture quality possible which means investing in the higher quality component, S-video or other higher-than-composite-video signals depending on the video switcher you select.

Many video switchers offer multiple audio input/output signal routing along with their video routing capabilities. For example, the Panasonic MX-70 8-input component switcher mentioned above includes a built-in 4-channel stereo audio mixer featuring standard XLR inputs and outputs. Some scalers offer similar built-in audio ins and out, albeit usually with RCA-type connections. These types of audio mixing capabilities may come in handy during post-production or for small “live” event presentations and productions. Although a nice touch, rarely will you route your audio through the video switcher or scaler for week to week worship services. Perform audio routing/mixing where it belongs— through the main sound console.

I like to view video switchers as more “creative” primarily due to their ability to provide seamless video layering through the strength of their just-mentioning keying and manual transition capabilities. These strengths become especially essential in “live” concert, convention and other special events requiring fast and efficient blending of multiple media formats and elements.

Until recently (the past 5-8 years) video scalers were largely the domain of mega churches, large production companies, corporate video suites or big budget production studios. Today, the availability of easy to use, affordable video scalers are a very viable solution for churches looking for a seamless video integration solution.

As already mentioned, the primary strength of scalers over video switchers is their ability to output high-quality, multiple resolution VGA video signals. This is especially important (and noticeable) when displaying computer-generated (PowerPoint, etc.) images, text and graphic which remains the “killer app” within houses of worship.

Although many higher end scalers offer true overlapping video dissolves most of the scalers appropriate for the large majority of small to mid-sized church budgets accomplish seamless transitions between video sources by “dipping to black” as they transition from source to source. This is not entirely undesirable.

My biggest “beef” with the current crop of scalers is the speed (too fast!) at which they perform this “dip to black” transition. Even the “slow” setting is about twice as fast as I would like to see for achieving even less abrupt on-screen transitions.

Some scalers offer PIP (Picture-in-Picture) features with the ability to control PIP size and position. Built-in time base correction can improve the quality of sub-standard (read VHS and/or amateur) video sources. Wireless and RS-232 control are common among scalers as are the ability to select from a large number of output resolutions. The plan is to maximize picture quality by matching computer’s output resolution, the display devices resolution (video projector, LCD or Plasma panel) with the scalers resolution. Scalers can “rescale” unmatching source and destination resolutions but this is done at the cost of picture quality and is always “Plan B”.

Most scalers are designed for rack mounts and provide very easy to use one-button switching which is ideal in such a volunteer-intensive environment such as a churches media ministry. A “freeze” function is another helpful feature common among scalers which allows you to freeze the output in order to test or preview other scaler functions or sources without disrupting the projected image.

Earlier in this article I promised to highlight at least one unit which qualifies as a true switcher/scaler. Such qualifications include the ability to directly input and output both video and PC sources. Although not the only kid on the block, the Edirol V-440 HD is one such unit. Priced at approx. $11,000-$13,000 the V-440 HD is not what you would call an impulse buy but considering it’s capabilities it is one of the best values in video switching/scaling available today. The V-440 HD is capable of seamlessly processing and switching between 4 SD (standard definition) and 4 HD (High Definition) sources helping satisfy todays and tomorrows switching needs. This is especially notable during the current SD/HD transition period we find ourselves in. With powerful keying, 4:3 or 16:9 aspect ratios and multi-format capabilities it offer’s a high degree of flexibility. Although not unlike all switchers (and switcher operators) it’s not perfect. But it is a currently-available solution demonstrating the types of features and functions you’ll want to consider as you “kick the tires” while switcher/scaler shopping. (note: I’m NOT an Edirol dealer!)

DOOR #1, or DOOR #2
It’s time to make a decision. Hopefully both the decision between scaler vs. switcher in general and which model in particular is one which you have the luxury of making apart from the pressure of a looming deadline. This will allow for adequate research and “shopping around” once a specific model has been selected. Here are a few primary considerations you’ll want to keep in mind as you pursue the perfect (ok, near-perfect) video switcher or scaler.

Whether you’re making an initial investment (leap!) or upgrading pay close attention to the reality of how many inputs you need. If you need 4 inputs immediately don’t buy a 4-input unit. Plan for expansion and growth (what a concept!) and think long-term by purchasing at least an 8-input unit. The number of outputs (regardless of signal type) is also important though somewhat less crucial since they can be multiplied via DA’s (distribution amplifiers).

Closely connected to quantity is quality. The type of signals you need to input and output can help determine they type of unit best suited. Are you majoring in displaying single or multiple computer sources with a “minor” in DVD playback, with nary a camera in sight? Then a low-to-midrange video scaler with 2-4 VGA inputs plus 2 video inputs (composite, S-video or component) may be just the ticket.

If you are mixing between multiple cameras, computers and DVD players, then a combination switcher/scaler should be considered. Output type is just as crucial. Remember, the goal is to feed your video projector(s) a single cable/signal such as RBG, component, composite, Y/C, etc.. Obviously you are running RGB cable to your projectors, so you do not want to invest a video switcher that does not have any RGB outputs.

If yours is a largely volunteer driven media ministry, and you are fairly certain that the video switcher operator will be a volunteer for the foreseeable future, then make sure whatever unit you purchase does not require a degree in computer or video technology engineering. Although training is a must no matter what technology you decide on, some units are more intuitive than others. When possible, renting a unit for a few weeks is a good way to lower the risk of investing in technology which doesn’t match your team or ministry.

You may not know the techno jargon (keying, matte wipes, frame sync, etc.) but everyone knows how to describe what it is they want to accomplish. (“We want to overlay text on top of a “live” camera image”, “We want to fade between two computers, two DVD players and satellite feed”, etc.). Decide what you want to do, or do better and pursue those technologies which allow you do that efficiently and elegantly. By using the web to research specific models (see sidebar) and manufacturers (see sidebar) you can quickly narrow down your options and discover a model matching your needs.

The proof is in the pudding. That is, putting the unit’s image output on the screen of the display device such as the video projection unit, LCD, TV or Plasma screen. If you want to compare the differences in quality between the different types of input and output signals of any particular unit, record short back-to-back test recordings on the same DVD or master tape using different connections. Look for units touting internal image-enhancing technologies such as noise reduction, image scaling engine, TBC, and ProcAmp.

Speaking with other ministries, individuals or organizations using the unit under consideration is one of the best ways to make an informed decision. Why did they buy that particular unit? Is it living up to their expectations? Has it required repairs?

This is a primary concern with any large ticket technology purchase. How difficult and expensive is it going to be should the unit need repairs or replacement? Is there a reasonable manufacturer’s warranty? Does the company selling me the unit have a reputation for fast, reliable, affordable service and support? Fortunately it has been my experience that although video switchers and scalers are highly sophisticated components they general have very few moving parts and tend to provide many years of reliable, maintenance free operation.

When dealing with technology obsolescence is not a question of “if” but “when”. By thinking ahead and making some basic media technology decisions, you can at least postpone obsolescence by investing in technology today which will at least have the ability to meet the needs of some of your media ministry “tomorrows”. Although I happen to believe that very few churches (and I do mean VERY few) will be needing/using HD video (shooting, editing projecting and/or broadcasting) within the next 5-8 years, if HD technology is part of your current system or future plans, by all means future-proof your media system by investing in an HD-capable switcher or scaler today.

Adding or upgrading your media ministry’s video switching and/or scaling capabilities is an important step in ensuring that your technology will enhance and not impede your ability to accomplish your unique ministry goals next week and next decade. Thankfully today’s video switching technologies offer a wide range of non budget-breaking solutions. No doubt there is one out there with your name on it.

Stand by camera #1…

…take 1!