[opendtv] Re: Case for 720p60
- From: Craig Birkmaier <craig@xxxxxxxxx>
- To: opendtv@xxxxxxxxxxxxx
- Date: Thu, 22 Apr 2010 11:32:38 -0400
At 10:30 PM -0400 4/21/10, Tom Barry wrote:
Well, let's let everyone be the judge, on whatever displays they have
available. I've posted 3 images on my web site. The first is a fairly
detailed 1920x1080p image. See:
...
Anyway, apart from that, what does everyone think? Would you pay much
extra for 856 vs 704 wide?
Thanks for taking the time to put these images together Tom.
A few observations.
First, we don't look at still image much on TVs, at least in terms of
video streams. It is much more difficult to see fine details in
moving video because the information our eyes see is constantly being
updated. My guess is that many observers would not be able to tell
the difference in resolution of any of these images on a 1920 x 1080
display, at least until the display size exceeded 70 to 100 inches.
Second, the discussion was not about multiple conversions, although
clearly there will be a wide range of displays in use. The real issue
here is how good can 480p be as a bandwidth conservation tool,
especially for multi-channel broadcasting and/or as a means to
deliver more channels in less bandwidth as the FCC is proposing. From
these images it is clear that good 480P can hold up very well and is
quite watchable on large 1080P displays.
It might be more helpful to directly compare the downsampled 480P
images. Again I think the differences would be minimal, but visible.
And there is also the issue of the quality of scaling used in most TV
receivers. It is well known that scaling by small factors typically
does not produce quality as good as when the scaling factors are
large. In the case of 720 versus 854 samples per line the difference
is about 16% which should be large enough to minimize this issue. But
it is always best to NOT scale when possible, which makes square
pixel 480P a better choice for smaller displays, especially
handhelds, and computers that do not have the ability to display 1280
x 720 directly (i.e. many Netbooks).
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:
