Switches, in many ways, work like a translator device. They basically help devices to speak the same language so that they can 'talk to' and understand each other. On the other hand, interface is the language itself. It helps devices communicate to each other. Together, they connect and control a wide range of AV systems. If you've been into computers and stuff all these times, both of them must be familiar sights although not necessarily good acquaintances. More often than not, people will recognize it visually but not by their names. An easy example, you may have no idea when Analog RGB or D-Sub is mentioned but you certainly do know where to plug in your cables in PC or notebooks when using a projector. They are called interfaces. Next, you want to view images with certain resolution from PC up in a bigger screen such as a TV. You cannot just go and connecting cables. You will need switches, in this case a scan converter, to convert the image to match the native resolution of the TV. With different switches, you can easily convert and set different input and output for your contents. You can scale up, scale down, divide source or route input signal. All you need is getting the right switches.
While there are dozens of switches out there to choose from, you will have to first know your own needs. Never do something like randomly buying switches because they look alike or look similar to what you remember. You have to understand the specification of each item and their applications. Some switches offers up to more than five inputs and outputs while some others comes with integrated multi-format switcher. When combined, you can easily control numberous devices at single time. Up next, you will also need to take a close look at compatibility aspects. Will the switches be compatible with other electronic devices you usually use? Do they have the required support for universal input and output formats? Miss a thing and it will cost you dearly. Performance also comes into consideration as the goal of using these devices in the first place is to optimize content quality when viewed in displays other than native sources.
Scaler vs Scan Converter
Converting contents from one source to display in different devices is probably the most frequent setting for you to deal with switches in daily life. You may want to either scale it up or scale it down, depending on the needs. To scale up or known as upscaling, you need scaler whereas scan converter helps with downscaling task. They are different separated, if not opposite switcher. But nowadays you can actually find a universal or multifunction switcher that integrates both scaler and scan converter in one place.
Scaler, in its most basic application, serves to convert video signal or content into higher resolution in order to be played in different audio visual systems such as TV, home theater, projector and alike. In audio visual scene, the process of converting contents into higher resolution is commonly known as upscaling and thus scaler is sometimes called upscaler. It can either be embedded in the systems or comes as standalone attribute in a separate box. Its general use are mainly for digital consumer electronics devices where image quality are to kept for different outputs. As such, it is important that you ensure the output resolution of the scaler is the same as the display. By matching the output resolution, you will also be able to make the most of the area of the display to view contents. Mind that scale up contents is not the same as getting it stretched. You does not simply pull contents to fit the screen. the Aside of keeping images and videos at its peak quality, scaler also reduce needs to install various different attributes and cabling. To synchronize video signal in display, you only need analog RGB connection. However, other standard such as DisplayPort, Digital Visual Interface (DVI), and High Definition Multimedia Interface (HDMI) slowly outdo analog RGB both in terms of popularity and common use in modern digital electronic devices these days. By reducing the needs to switch between inputs, users also save time and thus increase productivity. Practically, you can scale up contents to several kind of resolution to match different purposes. The most recent standard even allows you to do upscaling up to 3840 x 2160 pixel, or widely known as 4K which is four times higher of full high definition.
While scalers offer apparent advantage to AV systems, you may want to look out for possible imaging issues such as banding, scaler ringing, and double scaling. Artifacts or banding is the most common issues you encounter when doing video upscaling. It happens when the color tone output degrade from original source due to the insufficient color depth supported by the output device. The scale up only increases the number of pixel but have no effect on color depth and tone. The color changes are often abrupt that it creates a totally different impression like posters. But in some recent models such as the one from Extron, the issues can be minimized or even eliminated with enhanced scaling technology. Sometimes, they even combine switcher and scaler to keep ultimate image fidelity .
The opposite of scaler, scan converter downscale video, which is to convert video into lower resolution. The conversion itself can be done through both analog and digital methods with difference in image quality. While the process of downscaling do decrease the resolution, digital conversion retain a significant level of image quality. A lot of scan converter is used to convert computer-based video for displaying on television. Other applications including teleconferencing and video taping. To scale up is a choice but it’s not the case with downscaling. Considering the lower quality of image produced, one should really consider if they really need to use converter and for what kind of applications. And even if you are aware of these things, the next challenge is to choose the right scan converter for you out there.
Speaking generally, there are at least three type of scan converter based on the usage scenario. The first being the consumer grade which include scan converters that costs around $200 to $800 and rely on software to do the conversion. Although it is the most afforadble of the three, you will also have to do a lot of compromise on image quality aspect. That aside, consumers must also be aware of limited compatibility and features it offers. As with the professional grade converter, you got better image quality thanks to the real time interpolation technology. Its prices range between $1300 and $2400 and is generally capable of handling various kind of inputs. To top things off is the professional broadcast grade which retains highest image quality. It uses the same interpolation technology as professional grade converters do but runs faster with greater precision. The best ones can cost you very dearly up to $8000. If you are willing to break the bank, then go ahead. Only make sure that you really cannot afford any compromise.
All in all, switcher and interface are primarily tailored to allow seamless communication between devices if you choose it right. There are many of categories of switcher available, each with different function on their own. Aside of scaler and scan converter, there are also matrix switchers, distribution amplifiers, and multi format signal processors. Just make sure they fit for your requirements and applications while still reasonably priced.