What does 'image constrained HDTV' look like?

>> I tend to think this resolution is good enough for enjoying movies.


Huh? Who paid you off, Frank?!


I can "enjoy" a movie watching a poor 3rd generation VHS tape if the movie is worth

watching, but that doesn't mean that I am

happy to settle with "good enough".


If a full 1080i version is available I would

much prefer to watch that than some butchered

version that someone said is "good enough"

for me to watch.


Pan/Scan 4:3 NTSC is "good enough" to "enjoy"

most movies as well, but I still prefer

to see them in OAR if possible.


Are you the same Frank that has complained

that a movie with too much "open matte"

becomes unwatchable?

Quote:
I'm uncorruptable. So far.

I didn't say anything about aspect ratios.

I dare anyone to find any of my many posts that says anything positive about pan and scan.

Go ahead, make my day.


All I'm saying is that movie watching at home is already enjoyable via DVDs. Image constrained HDtV would be substantially better then that. That doesn't sound so bad to me.



Frank

Frank,



Interesting question,


I see from a recent post of yours you siad you fully beleive hbo hd is constrained. Are you not sure now? If you are. I guess you already know the answer.


btw which was better looking to you pbs 480p or the hbo hd?


YOu are consitant in the same post you siad why would this bother anyone if they enjoy the picture they are geting.


--tony


maybe someone can tell us how many pixels make up a dvd image and compare that to the number of pixels in a 980 x 540 image; for some mental reference.

Quote:
In a post on OpenDTV in about April of this year concerning the high quality of Ocean's Wild:


"Thanks for your comments, but PBS is not running any standard

definition in 480p at this time. What you saw was 16:9 480i. The

availability of 480p equipment within the public television

production chain is not to the level yet where programs can be

produced in 480p.


The difference you see is not only the wider screen, but the

quantifiable difference between 480i decimated by NTSC encoding to

Just for reference:


1080i: 1920x1080 (2,073,600=100%)

720p: 1280x720 (921,600=44%)

"constrained" 1080i: 960x540 (518,400=25%)

DVD: 720x480 (345,600=16.6%)


So DVD has only about 16% of the raw

"pixels" of 1080i HDTV


DVD has about 2/3 (66%) of the pixels of

"constrained 1080i".


==============================================


And yes, I think Frank is sounding like

an out of character "turncoat" in this topic!


If there were a valid technical reason why

we should be pushed into giving up 1920x1080

for 960x540 then maybe I could go along

with the idea of it being "enough for now",

but the fact of the matter is that

"constrained" HDTV is being pushed on us

as some sort of "sacrifice" to appease the

content providers. Personally I think

reduced res 1080i is not the answer when

the real concerns are with the digital

streams. If everyone has a HiPix card

or someone develops a "5C defeat" box then

who cares about a few people with W-VHS

recorders?

Quote:
There are no digitizers (now) but there are WVHS recorders of same, which posters here have stated produce very high quality copies. They're not worried about the average consumer digitizing the HD analog, but if they continue to output "high value" content in full HD over analog outputs, as though they don't care whether people copy and distribute it as they please, people will create highly accurate digital capture devices for it.


To address the main poster's question, "What does 'image constrained' HDTV look like?", I don't think that anyone can answer that as yet. Since the 520,000 pixels a frame can be made up of can be derived by crunching the original image any way you please, it could be much more beautiful than any line-doubled STD DVD has ever been, though never as pretty as the original. However, one has to ask what motive the manufacturer has to make it look pretty, since if they're making a recorder, player or STB with 1394/DTCP connectors and analog HD outputs, they're probably also making or planning to make televisions with protected Firewire connections too, and they'd prefer that you buy one of them than become satisfied watching "constrained images" on your old set with only analog inputs. Only Echostar has no such ulterior motive, unless they're taking kick-backs from the CE OEMs under the table .


gridleak has posted here about his experiences with the Japanese version of the HM-DH30000--he and other posters here have seen it constrain images. He talks a little bit about it in his last two posts at the bottom of this page. The down-rezzing seems to have been first discussed here and further hashed on here .



-- Mike Scott

Quote:
HiPix is a PCI-bus card that tunes ATSC for capture and display. It could possibly be used to make digital copies of HD stuff from the DISH 5000/Modulator combo, unless that, too, has been made sensitive to embedded CMGS CCI fields in the MPEG-2 stream, or something else in DISH's proprietary encoding. It will not help to record copy-protected stuff transmitted over 1394/DTCP or DVI/HDCP because it lacks either connection and is not licensed to speak either protocol.


I predict that a "5C defeat" box would take a huge, expensive effort to create (breaking "Full Authentication" will be extremely difficult--stealing authentication certificate signature keys from the manufacturers will be easier), be very expensive and will only work until the DTLA gets their hands on one and can put the keys its using on the Certificate Revocation List for distribution over DBS, cable and on new prerecorded media.


-- Mike Scott

Quote:
I don't believe this is very accurate. 1080i is 30 frames per second (fps) and 720p is 60 fps. So to redo your calcs:


1080i -- 1920x1080x30 = 62,208,000 pixels per second (pps) = 100%

720p -- 1280x720x60 = 55,296,000 pps = 88.8%

(You can extrapolate the rest)


I believe this is why most people see 720p as 'almost as good' as 1080i. In fact, it is about 90% as good. Your example assumes a static image (i.e.-computers) whereas most video is always moving somewhat. Even with little object motion there is usually panning and zooming changing objects screen position, so this just doesn't apply to sports.

Alot of displays (like DLP, LCD, dILA)

"buffer" the image and scan the image at

their own native display rate... So

30fps or 60fps doesn't really have the

same impact.


There is a valid point to consider

examining the actual full frame resolution

(in overall pixels) not just the

"pixel datarate".