At 11:09 AM -0500 4/19/10, Manfredi, Albert E wrote:
Craig Birkmaier wrote:What is lacking here is any discussion of the fact that most folks are still watching, and most stations are still broadcasting interlaced SDTV...In ATSC-land, where there are no MPEG-2 MP at ML restrictions, in principle at least, broadcasters could begin to transmit SDTV as 480p24 or 480p60. So why don't they?
The only 480p format that could be used is square pixel 640 x 480 with a 4:3 aspect ratio. The ATSC does not support 854 x 480p or 704/720x480p. These formats are supported by MPEG-2 at various levels, but there is no guarantee that all ATSC receivers will display them, so broadcasters do not use them.
One of the NBC4 subchannels is Universal Sports, now using 480i. It probably doesn't make sense to try using 480p24 for sports, so they would have to use 480p60. If it's true that MPEG-2 compression is so much more efficient in progressive mode, are the advocates of progressive saying that the US subchannel could be transmitted as 480p60 over the same ~2.5 Mb/s channel now used for 480i?
Sure, but only using ATSC approved formats as described above. Regards Craig ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways:- Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org
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