The only reason I mentioned H.264 is because we know TVs decode H.264 from DVB-T broadcasts.
Except that very few DVB-T TVs CAN decode H264 internally. AFAIK all DVB-T IDTVs sold in the UK and Western Europe are MPEG2 SD only. They decode the MPEG2 SD in hardware (often using the same chipsets as STBs) - and this hardware doesn't support HD MPEG2 or H264 in either HD or SD. It is engineered down to a price - and SD MPEG2 is cheaper to implement - if you take these sets to Australia they don't decode their HD MPEG2 DVB-T broadcasts, just the SD (if they are compatible at all - as there are a few differences in implementation)
Some countries ARE going H264 via DVB-T for Pay TV services (France), HD-only (Sweden is H264 via DVB-T for SVT HD, but MPEG2 for everything else) and all broadcasts (Latvia or Estonia?) - but AFAIK these require external set top boxes.
The BBC DVB-T HD trial was only received using set top boxes, no IDTVs received it.
Any OTA HD in the UK is likely to be DVB-T2 not DVB-T anyway - and this standard has yet to be officially ratified and finalised AIUI. (BBC Mux B is likely to switch from DVB-T to DVB-T2 at around 30Mbs after analogue switch-off, with BBC Mux 1 switching from 2k 16QAM 18Mbs to 8k 64QAM 24Mbs allowing - Ofcom hopes - BBC Parliament, BBC Four/CBeebies, and 301/302/303 video streams to all fit into the space freed up...)
And any H.264 decoder which could decode a 720x576@66fps stream, could just as easily decode a
[email protected] stream and a 1920x1080@13fps stream. Resolution is only one factor of the real limitation of a decoder, which is data rate ( H.264 "levels" ).
Yep - but MPEG2 decoding is usually implemented in hardware and limited to SD resolutions in European models. There are no DVB-T IDTVs that I am aware of with H264 decoding hardware.
Lots of current TVs are DVB-T
EN 300 744 compliant which seems to require accepting video streams up to 30MB/s... and a hi-quality 1080p stream only uses about 25MB/s with H.264 compression.
Yep - DVB-T requires a potential max of 30Mbs - though in the UK we max out at a 24Mbs transport stream. HOWEVER DVB-T doesn't mandate H264 - only SD MPEG2.
IDTVs sold in Europe are MPEG2 SD only...
Thegeby was just saying you can't buy a TV in Europe which could accept a terrestrial HD broadcast and display it ( in HD ). I don't know how anyone could say that's correct, because that's pretty hard to test, right now.
Not difficult at all if you were in London during the tests, or in Sweden right now. Both use(d) H264 via DVB-T - and although IDTVs often found the service, they couldn't decode it.
Any new TV which can accept a DVB-T broadcast might process a HD stream without any problems... I can't find anything excluding that possibility.
Lack of H264 decoding, or even HD MPEG2 decoding (outside Aus) would be the reason.
But yep, you're right. I was presuming a H.264 decoder would output directly to the same frame buffer as all other HD sources. If the DVB-T tuner had its own smaller buffer, it'd select a lower level stream. The DVB-T tuner might "
accept" a 30MB/s stream, but who knows if it'd "
process" it.
It wouldn't if - as is standard - only an MPEG2 SD decoder was implemented.