Originally Posted by RikasAngel
Let's say for the sake of argument that an ATSC II standard was adopted and implemented. Could stations broadcast multiple high quality 1080p signals using MPEG 4? If so, up to how many could they broadcast? I've read at least one person mention that a statation could have three 1080i channels using MPEG 4. I'm curious about the possibilities MPEG 4 could present.
In Norway, NRK run 3 x 720/50p channels and 2x576/50i channels using MPEG4 in a single 22Mbs DVB-T mux. Picture quality isn't too bad. They use 70kbs for HE-AAC 2.0 and 200kbs for HE-AAC 5.1 audio. (AC3 isn't used)
In the UK the BBC operate with 4-5 x 1080/50i channels using MPEG4 in a single 40Mbs DVB-T2 mux (they sub-let capacity to ITVHD and C4HD, and broadcast BBC One HD and BBC HD, and during the Olympics BBC Red Button HD). (Some of these channels switch dynamically between 1080/25p and 1080/50i based on programme content) Again, picture quality not too bad. Certainly a lot better than a lot of the US OTA MPEG2 stuff I've seen whilst on holiday in the States.
In both the Norwegian and British examples, statmuxing is used, where the pool of 22/40Mbs of data is shared dynamically between channels based on content.
When it comes to 1080p "proper" broadcasting, the only 1080/50p stuff I've seen has been on satellite. This was actually for 2160/50p broadcasts (aka 4k) which is being trialled by sending 4 quarter-screen 1920x1080/50p streams (Using H264 at Level 4.2 not the more usual Level 4.1 normally used OTA and for Blu-ray etc.) The broadcasts I've seen use 4 x 9.5Mbs H264 streams for reasonable, though not stellar, 1080/50p.Edited by sneals2000 - 3/12/13 at 10:11am