We've been having a lively debate about HD this week at Narrowstep. The question is, what is HD ? Or rather, what can pass as HD ?
Two of Narrowstep's channels (London TV and Single Malt TV, check them here on Vidzapper), already film most of their content in HD (and, boy, does it make a difference, even when encoded down to 800Kbps). But the maximum transmission on Narowstep's telvOS platform is currently 1.8Mbps. Still, if I flick between one of these channels and BBC HD, the difference is not huge, and when it comes to sporting events, the difference is less still.
I've heard on good authority that HD on existing broadcast platforms is put out at around 4Mbps (even this is compressed by a factor of 300:1 - a pure HD signal is 1,500 Mbps), although common consensus is that it should be 6 - 8 Mbps (which is what you get when there isn't much contention - ie viewers - on the service).
So, the technical specifications don't mean much here, but to avoid confusion I have suggested using the term 'HQIV' (high quality internet video) for video delivery that is technically not HD, but looks like it to the consumer.