[opendtv] Re: Samsung Rep admits HDMI won't support 1080p until v.1.3
- From: Craig Birkmaier <craig@xxxxxxxxx>
- To: opendtv@xxxxxxxxxxxxx
- Date: Tue, 8 Nov 2005 07:43:01 -0500
At 10:09 AM -0800 11/7/05, dan.grimes@xxxxxxxx wrote:
>"What we need is HD source that has not been trashed by excessive
>compression in the distribution chain." --Craig Birkmaier
>
>Amen!
>
>But don't you think that it would be good to have 1080@30p production? I
>realize that this requires more bits, but interlacing is also a big
>problem. Or do you think that 720@30p is good enough? While I hope for
>1080@30p production, I would rather have only 720p production if it removed
>most of the artifacts.
30P production is certainly possible today, but it is rarely used.
Like 24P it presents problems with rapid motion, and one must be very
careful with camera moves and zooms. Generally speaking, if a
producer is looking for that "look" they will choose 24P.
That being said, a great deal of streaming media content that is
available via the web is limited to 30P, even if the original source
was 24P. The need to conserve bits for web streaming may lead to
greater use of 30P, but for now, it seems that 24P and 60P are the
most common HD acquisition formats for the U.S. - whoops, I almost
forgot 1080@30i.
>I want to mention (though beating a dead horse) that I was so frustrated
>with the compression artifacts watching NASCAR yesterday that I went to my
>old NTSC TV. But the artifacts were so bad, even the low resolution
>picture looked bad! The distribution chain needs fixin'!
Yup. ANY 60P format with high motion is still difficult to compress
into 18 Mbps for an ATSC channel, and if that channel is being shared
for a multicast or other services (like USDTV channels) then it is
likely that all of the programs will be compromised. H.264 can help a
great deal, but it is not an available tool for OTA broadcasts.
This is one of the reasons that we pushed for lower spatial / higher
temporal rate formats for DTV broadcasting. You can distribute
spectacular pictures by encoding about 1/2 million pixels - e.g. 1024
x 576@ 60P. You can still acquire the source at 1280 x 720@60P, then
simply re-sample prior to compression for emission.
Unfortunately, most broadcasters are still hopelessly hooked on
"FORMATS;" they have a very difficult time with the concept that they
are just delivering bits that can represent pictures of any size or
frame rate. In this, the web video folks are light years ahead.
The folks with plenty of bandwidth abuse what they've got and deliver
crap, while the folks trying to build a business with a distribution
network that is very constrained, are the ones working hard to
improve delivered video quality.
Go figure.
Regards
Craig
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
Other related posts:
