Europe: HD Ready? article

[drgagx]

I came across this article while browsing
http://www.videsignline.com/showArticle.jhtml;jsessionid=3OBKO2ABOUMSAQSNDBCCK HSCJUMEKJVN?articleID=163102011

It is a discussion of issues for the implementation of HDTV in Europe. Apologies if it has been referenced before.

Tho I do not pretend to understand most of the technicalities involved, two things caught my eye:

[1] the table revealing that MPEG4 Mbit rates are only about half those of MPEG2.
This prompts the question, when will we see this in practice? I recall reading recently that Quicktime is close to the final release of an MPEG4 version. A further question is what are the implications for future releases of HD/HDV camcorders? I see that Panasonic already use a low res version of MPEG4 in their low cost D-Snap range for recording to SD cards. Presumably HD versions wait on increased SD card capacity.

[2] under the section entitled HDTV and Terrestial Digital TV there is a reference to "hierarchical modulation...allowing the transmission of two separate transmission streams over the same transmitter". It states that "a possible application with HDTV is to broadcast the same content on both streams". This would enable both SDTV reception via simple antennas and HDTV with fixed rooftop antennas - provided, that is, everyone has a set top box.

[infocus]

I came across this article while browsing
[url][1] the table revealing that MPEG4 Mbit rates are only about half those of MPEG2.
This prompts the question, when will we see this in practice?.

AFAIK with the introduction of Skys HD service, so probably within a year. I believe France is starting DTT with SD and MPEG2, but with provision for future HD and MPEG4. I don't believe MPEG4 is all gain and no pain. Important within all coding systems are processing power needed to implement it, and latency. The formers pretty obvious, the latter represents (crudely) the delay to the signal involved in the coding. Listen to an analogue TV and a Freeview one at the same time to get an idea! It's not too important for Freeview, say, but think of the feeds to such as a news studio from a reporter from the field. Long pauses before the reporter answers are most definately not wanted! Quite simply, all else equal, MPEG4 may reduce bit rates, but need more powerful processing and increase latency.

[2] under the section entitled HDTV and Terrestial Digital TV there is a reference to "...allowing the transmission of two separate transmission streams over the same transmitter". It states that "a possible application with HDTV is to broadcast the same content on both streams". This would enable both SDTV reception via simple antennas and HDTV with fixed rooftop antennas - provided, that is, everyone has a set top box.

Yes, and I believe in Australia hierarchical modulation has been tried. I think the total data rate for the HD and SD services is the same as for an all SD multiplex in the same channel, with the same modulation system (ie 16QAM/64QAM), so I don't know how suitable it would be in the UK. Also interesting in the article are the references to DVB-H, and it competing for spectrum with HDTV. In a future world it would be nice to think of DVB-H catering (robustly) for phones/handhelds/small(14")tvs and HD for bigger - all for the way up to 50" and more. Current Freeview is not good enough for big screens, but too good/not robust enough for small.