The importance of scaling in a “not exactly perfect” video world
In a perfect video world, scaling is not required. For example, broadcast-quality video has exactly the right resolution, correct number of lines, and a refresh rate of precisely 59.94 or 29.97 Hz. Everything in the video chain conforms to broadcast standards, so system integration and video processing works seamlessly by design.
However, in the AV Integration world, “not exactly perfect” video has to be expected, fixed and sent on to its destination. Apple’s 1080p is not the same as Windows 1080p. The refresh rate of a PC is rarely a straightforward 60 Hz, usually wandering somewhere between 57 to 63Hz, and the aspect ratio is often 16:10.
HD encoders, and their ability to accept non-standard HD video, have evolved over the years. Early encoders had no video adjustments – if the video was not broadcast-standard (1080i/720p 29.97/59.94 Hz) - it could not be encoded. The next option, common for consumer encoders, was a “dropbox” solution where most video could be “dropped” into a 1920 x 1080 or 1280 x 720 frame. Non-standard video could be cropped or off-center. The idea was the homeowner could tweak the size and placement if they had a high-level graphics card to handle the scaling.
QMOD Encoder-Modulators use a full hardware scaler for both encoders. In most cases, the video is automatically fitted to the screen, and the installer can zoom, shrink and position the video if needed. In addition, the video can be fully up- or down-scaled. Video for 720p-only TVs can be fixed at 720p, or IPTV video could be upscaled to 1080p or reduced to 480p for smaller streams.
When we created the new QMOD and QIP dual-channel Encoder/Modulators, we made sure that each program has full scaling – hardware scalers, so that scaling doesn’t put a stress on our software. The process is more intuitive and intelligent, with little image tweaking required. Not only are most VGA resolutions supported, but the scalers can handle 1080p, 60/59.94, 30/29.97 and PAL formats as well.
The ability to downscale is a great feature for IPTV streaming from QMOD and QIP encoders, dropping 1080p video down to 720p or 480p streams saves a lot of network bandwidth.
We added scaling because we’re an integration-centric company, and we want installation to be simplified and hassle-free. Getting rid of video “gotchas” is a big part of that goal.