[opendtv] Re: Case for 720p60
- From: Tom Barry <trbarry@xxxxxxxxxxx>
- To: opendtv@xxxxxxxxxxxxx
- Date: Thu, 22 Apr 2010 11:45:30 -0400
Morning Bert -
I purposely used the least jpg compression available for these since I
wanted to show just the differences in resolution, not compression
artifacts. My own thesis is that if 704x480 was degraded by compression
the 856x480 would be even more so.
480i would be the worst. On a modern display you have to first
deinterlace it and then scale it up to the native display resolution.
That way the upscaling tends to amplify all the deinterlacing
artifacts. The people that write deinterlacers know that so they try
to hide them by filtering a bit, further destroying detail.
And of course I'm still a fan of higher resolutions. I just wanted to
get some samples out there so we would all have a better idea of some
off the trade-offs we are talking about.
- Tom
Manfredi, Albert E wrote:
> Tom Barry wrote:
>
>
>> The first is a fairly detailed 1920x1080p image. See:
>>
>> <www.trbarry.com/spring_2008_1920x1080.jpg>
>>
>> The second image is the result of using Irfanview to scale
>> this down to 856x480 and then scaling back up again to
>> 1920x1080 to match what your 1080p TV might display.
>>
>> <www.trbarry.com/spring_2008_1920x1080_from_856x480.jpg>
>>
>> It of course has visibly less detail than the 1080p image.
>>
>> The third image is the result of scaling the first 1080p
>> image all the way down to 704x480 and then scaling back up
>> again to 1920x1080. See:
>>
>> <www.trbarry.com/spring_2008_1920x1080f_from_704x480.jpg>
>>
>
>
>> Anyway, apart from that, what does everyone think? Would
>> you pay much extra for 856 vs 704 wide?
>>
>
> Nice! I'm toggling between among the three pictures, on a 1680 X 1050
> display, set to 1680 X 1050 in my display setup, and viewed up close. The
> three images are exactly superimposed, using three tabs on IE8, so there's no
> shifting of eyes between images. And I'm focusing on whatever it's called in
> the middle of the central flower, with little tentacles and black dots on the
> tips.
>
> Since my display is only 1680 X 1050, the goodness of the 1920 X 1080 image
> will obviously be muted somewhat. I'd say subjectively, though, that the 1920
> X 1080 image is still more of an improvement on the second image than is the
> difference between the lesser two images.
>
> But let's get back to reality here. The 704 X 480 SD stream, in a typical
> ATSC multicast, would be bit starved, as most SD subchannels are. So you
> wouldn't expect to see the ultimate quality anyway. I'm still wondering
> whether 704 X 480 at 60p can be sent at the same low bitrates that are now
> being used for 480 at 60i. And you would need to use 60i or 60p for sports,
> anyway.
>
> Sure would be nice if broadcasters started transmitting their SD multicasts
> as 16:9 anamorphic, though. I know that some of that material was shot
> widescreen, certainly in the US and the ThisTV multicasts.
>
> Bert
>
>
> ----------------------------------------------------------------------
> 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.
>
>
>
----------------------------------------------------------------------
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: