We use Wasp 3D (developed by our company Beehive Systems) for broadcasting in real time. The data is stored in a templatized format as a .wsp file (A wasp template file basically). This template, when queued to be sent on air, is encoded in an MPEG-2 or MPEG-4 format or using H.264 compression format or an advanced profile in WMV Pro format. The compression algorithm chosen depends upon the channel really, rather than our decision because we produce the software and motion graphics for the clients with live video feed playback capabilities and stored video playback as well, all in realtime.
This encrypted data is then sent through RF, MW etc. depending upon the factors the specific client channel has available. When this signal reaches a television, it is decrypted and displayed on your screen. The result is a lossy format, of course.
Also, I am still not very sound conceptually with how all this works, but this is the rough sketch of things.
