and bandwidth limiting methods that were required for analog broadcasting, as well as for the signal normalization techniques used in recording and mastering.
Audio codecs on the other hand are moving targets - each codec algorithm has its own set of artifacts. So not only does the sonic quality vary depending on the algorithm and bitrate used, but more importantly they vary in their ability to mask their own coding action. This is why we call it a ‘moving target’, and is why conventional audio processors fall short in a coded audio environment and can actually make coding artifacts worse due to their inability to adapt appropriately to the changing operation of the codec as the program content changes.
Prior art in audio dynamics processing could only address some of the challenges of provisioning audio for coding. This hurdle existed because the codec adapts to the incoming program (so as to generate the least amount of output data representing the input audio) causing the sonic artifacts generated by the process to continually change. Unless the audio processor can predict these changing characteristics of the codec, it can’t possibly create output audio that is perfectly tailored for the coding process.
Conventional processors utilize rather simplistic high frequency limiters and fixed low pass filtering that does not change with the program material. When these less intelligent processors feed a codec the audio might sound acceptable one moment and offensive the next. Because they cannot “know” what the codec will do next, the result is
OmniaONE Multicast and HD→ Radio
The advent of HD RadioR has introduced the capability to transmit multiple program streams, or “Multicast”, within a single 96kbps digital broadcast data channel. To facilitate this, multicast relies on the use of codecs with comparatively low bitrates. A broadcaster can choose to transmit a number of multicast channels and select the bitrate for each one. However, the more multicast channels there are, the lower the bitrate each channel must have in order for them to all fit within the total available bandwidth.
In the very near future, many low bitrate multicast audio channels might exist. To achieve maximum sound quality, the kind that attracts and holds listeners, those channels will need specialized dynamics processing capable of creating great sound regardless of program content and bitrate. They will need Sensus→.
OmniaONE Multicast was designed from the ground up for provisioning audio for codecs operating at these low bitrates. With Sensus→, the innovative algorithm inside OmniaONE Multicast, it is now possible to have consistently high audio quality with a minimum of
OmniaONE Multicast creates highly listenable audio lacking the dull, muffled, ‘swirley’ sound usually associated with codecs operated at extremely low bitrates.
OmniaONE Multicast - Use and Operation Manual – Version 0.90
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