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post #6901 of 14496
7/9/05 at 12:06am
Quote:
Originally Posted by TPeterson View Post

But as a practical matter I really doubt that anyone can actually see a real difference between the two (on less than a 100" screen, anyway) that doesn't have to do with the 30-Hz flicker of interlacing.

On my 1920x1080 Sharp 45" using internal QAM tuner, there is a clear difference between 720p and 1080i from Comcast. On mostly static frames, 1080i is sharper and more detailed. On motion frames, 720p has more solid edges. On this particular display there is no flicker as 1080i is deinterlaced before display. It is possible with excellent scaler, 720p and 1080i would look nearly identical, but I'm just reporting on the stock equipment.

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post #6902 of 14496
7/9/05 at 7:15am
sfhub--

Thanks for confirming that on a genuine 1080p display it's a tossup.
post #6903 of 14496
7/9/05 at 10:53pm
Quote:
Originally Posted by keenan View Post

While 1080i has more pixels there are caveats that come with it. Since the only source that can come close to, or actually does in some cases, send that resolution is OTA, in most cases less, it can be argued that while 1080i has better spatial resolution the lack of full resolution actually being sent, or even resolved at the display, makes the tradeoff of 720p having better temporal resolution a more logical choice when looking for detail and lack of motion artifacting. For fast motion, close captured sports, such as basketball, boxing, most Olympic events, 720p makes more sense because of it's lack of motion artifacting. Football, being that most shots are from a distance can and do look excellent in 1080i, primarily because of increased detail, but also because with long shots the motion issue is much lower than it is with something like basketball.

Not to mention there are only a few displays even capable of displaying, or even coming close, to actual 1920x1080i resolution.

I should add, that to the best of my knowledge, these STBs from Comcast output about a maximum of 1350 lines of resolution anyway, so full 1920x1080 is not available to be utilized, even if you had a display that could resolve it. Hooking the cable feed directly to the display should give you the best chance at receiving whatever the original broadcast was sent at, if it's at a higher resolution than 1350.

Anyway, when the heck is Comcast-bay area going to get TNT-HD..


Best example of that is tonight's Battlestar Galactica on NBC-HD. 1080i is not the format for that show at all. Everytime they had a big fast paced space battle, artifacting was a mess. Crashes become pixelated for a split second...terrible really. Every network should go to 720p, for action shows at least.

EDIT: Here are links to some really nice 720p trailers. I love playing these on my laptop. Watch the Serenity trailer for a good example of why 720p is GREAT for fast motion scenes.

http://download.microsoft.com/downlo...ailer_720p.exe
http://www.serenitymovie.com/media/s...bit_LTR_NR.zip
http://download.microsoft.com/downlo...ights_720p.exe
http://download.microsoft.com/downlo...e/Ray_720p.exe
http://www.thebournesupremacy.com/tr...RD_NR_bt-1.zip
http://www.theskeletonkeymovie.com/m...it_LTRT_NR.zip
http://www.kickingandscreamingmovie....it_LTRT_NR.zip
http://www.theinterpretermovie.com/m...it_LTRT_NR.zip
post #6904 of 14496
7/10/05 at 1:03am
Quote:
Originally Posted by neoufo51 View Post

Best example of that is tonight's Battlestar Galactica on NBC-HD. 1080i is not the format for that show at all. Everytime they had a big fast paced space battle, artifacting was a mess. Crashes become pixelated for a split second...terrible really. Every network should go to 720p, for action shows at least.

Yes, the scene where Baltar was hesitating getting out of the ship with all the fire around him was a particularly bad pixelated mess. Even some close captured stuff like the scene with the President, her assistant and the Oracle character, when the camera moved from one face to the other, there was tiling. You don't see any of this crap on the DVD set.

The transitions from commercials back to the show were horrendous, with popping audio and scattered lines all over the screen.

Simply put, KNTV sucks, I would love to have seen what CBS could have done with this, even though they are 1080i as well, KPIX does not multicast and I have a strong suspicion it would not have looked like KNTV's broadcast.

It's a shame one of our 4 major networks apparently does not care about the quality of their signal.
post #6905 of 14496
7/10/05 at 1:24am
Quote:
Originally Posted by keenan View Post

Yes, the scene where Baltar was hesitating getting out of the ship with all the fire around him was a particularly bad pixelated mess. Even some close captured stuff like the scene with the President, her assistant and the Oracle character, when the camera moved from one face to the other, there was tiling. You don't see any of this crap on the DVD set.

The transitions from commercials back to the show were horrendous, with popping audio and scattered lines all over the screen.

Simply put, KNTV sucks, I would love to have seen what CBS could have done with this, even though they are 1080i as well, KPIX does not multicast and I have a strong suspicion it would not have looked like KNTV's broadcast.

It's a shame one of our 4 major networks apparently does not care about the quality of their signal.

Yep. I hated it. It was the first time I saw BSG in HD and I was annoyed everytime I saw massive tiling. The audio pops...oh man, that really ticked me off since I wanted to hear it on my system and nothing worse then hearing every speaker pop, considering that commercials were more frequent than usual on that show. I wish sci-fi went HD. I'm sure they would care very much about the signal...especially since us Sci-Fi geeks will raise hell the second we cant see a space battle in its pristine glory.

Yep, definitely sucks. I mean, even LENO looks bad. The background on stage has so much detail going on that one camera pan and its a mess.

One question...Its obvious KNTV looks horrible, but have people complained enough to them? This is just shameful PQ.
post #6906 of 14496
7/10/05 at 1:39am
Quote:
Originally Posted by neoufo51 View Post


One question...Its obvious KNTV looks horrible, but have people complained enough to them? This is just shameful PQ.

Yes, and we were told it was fine.. It was in response to some Olympic complaints in the Yahoo SF forum. I'm going to search back and find the quote, but essentially, KNTV doesn't really care too much about their HD signal at this point because it's not making them any money.

BTW, that Serenity clip is fantastic, and I'm only using a 1.5G machine..

I think I would have a heart attack if KNTV even came close to that quality...
post #6907 of 14496
7/10/05 at 2:19am
Quote:
Originally Posted by keenan View Post

Yes, and we were told it was fine.. It was in response to some Olympic complaints in the Yahoo SF forum. I'm going to search back and find the quote, but essentially, KNTV doesn't really care too much about their HD signal at this point because it's not making them any money.

BTW, that Serenity clip is fantastic, and I'm only using a 1.5G machine..

I think I would have a heart attack if KNTV even came close to that quality...

Jerks...oh well. I dont watch much NBC cept Leno if somebody really pretty is on the show.

Yeah, that Serenity trailer rocks. When the rockets go off or when there is a fly-by zoom, it holds up perfectly.
post #6908 of 14496
7/10/05 at 6:22pm
Anybody getting any audio-drops tonight on the ESPN HD Sunday night game (Giants & Cards)?
post #6909 of 14496
7/10/05 at 6:40pm
I haven't noticed any...
post #6910 of 14496
7/10/05 at 6:51pm
Yep, I've had some. Also seen some fly ball drops as well, but can't blame Comcast for those.
post #6911 of 14496
7/10/05 at 6:58pm
I've noticed audio-drops on ESPN HD for a couple of days now, but I didn't think much about them until tonight. Hope they get it fixed before the All Star HR Derby tomorrow night.
post #6912 of 14496
7/11/05 at 10:17am
Quote:
Originally Posted by TPeterson View Post

BZZZT! Wrong...thank you for playing. The data rate includes the fact that 1080i is 30 fps while 720p is 60 fps, so the ratio is far less than 2:1. Your statement would be correct if you were talking about 1080p, but there are no 1080p broadcasts (and, without much better bandwidth management strategies than we're seeing in OTA broadcasts today, using 1080p format would result in major macroblocking on a 19 Mbps ATSC channel).

Wrong? I'm not wrong. Those are the specs of those 2 formats, you can go look it up. Actually if you want to split hairs it's you who is wrong - 1080i is 60hz (60 fields per second).

720p only looks better if the same thing on 1080i gets compressed all to ****. Well.. duh. Believe me 1080i looks a HELL of a lot sharper. Of course you need a display that can actually show 1080i and not downconvert it to 720p like most of the digital displays do. Have you ever actually seen a real 1080i signal in full resolution? Sure 720p looks nice, but 1080i has much, much more detail. Of course it also has higher bandwidth requirements and if broadcasters are intent on multicasting 72 channels of weather satellite images instead.... but that's their problem. Take a look at any of the movies/etc shown on INHD if you get those channels (and if you have a real 1080 display) they don't over-compress and it looks fantastic, even the sports games.

Quote:
Originally Posted by jraisner View Post

Yep, I've had some. Also seen some fly ball drops as well, but can't blame Comcast for those.


FWIW I didn't see ... er.. hear.. any audio dropouts. Might be a local issue.
post #6913 of 14496
7/11/05 at 10:32am
Quote:
Originally Posted by walk View Post

Wrong? I'm not wrong. Those are the specs of those 2 formats, you can go look it up. Actually if you want to split hairs it's you who is wrong - 1080i is 60hz (60 fields per second).

I think there is some confusion in these replies. In on instance there is a reply to a set of posts discussing "bandwidth" saying 1080i is twice bandwidth of 720p, which clearly it is not. In the next reply the conversation has changed to pixels in a 1080p (deinterlaced 1080i) frame. These are apples and oranges.

I have a 1920x1080 display so I know what these things look like. 1080i is clearly sharper than 720p, but for fast motion scenes, the edges on 720p objects are sharper.
post #6914 of 14496
7/11/05 at 10:35am
walk--

Since when can "fps" not mean "frames per second"? Those 60 fields in a 1080i picture each have only 540 lines, which is why the ratio of data rates for 720p and 1080i transmissions, all else being equal, is about 1920x540/(1280x720) = 1.125 rather than the over 2 you quoted. Yes, static frames of 1080i can have much higher detail than frames of 720p, but the motion artifacts introduced by present compression strategies end up dominating subjective judgements of image quality in normal ATSC TV viewing.
post #6915 of 14496
7/11/05 at 10:44am
Quote:
Originally Posted by TPeterson View Post

Yes, static frames of 1080i can have much higher detail than frames of 720p, but the motion artifacts introduced by present compression strategies end up dominating subjective judgements of image quality in normal ATSC TV viewing.

There are many people on either side of the 720p vs 1080i debate. For my viewing content, even with sports, I think over 80% of any particular show I watch has slight motion, which looks great with 1080i. The fast motion only happens in bursts, so what dominates my memory of the picture is the overall sharper picture of the bulk of the frames vs the slightly more stable fast motion frames. Everyone will have their own opinion on this and it depends on your display and other factors.
post #6916 of 14496
7/11/05 at 11:01am
Yes but the fields are combined at viewing time (either by a de-interlacer if you're one of the lucky.. er... rich people to have a 1080p panel display, or by persistence of vision) so the effective resolution is 1920x1080. The horizontal resolution is higher regardless (1920 vs 1280) and even though my CRT probably only resolves about 1600 of those I can still tell a difference. It's not hard to see, watching the Giants games on FSN/InHD (1080i) vs ESPN (720p, well mastered, looks decent but a little softer) or FOX (720p, not well mastered, quite blurry actually). I mean they use the same cameras..
post #6917 of 14496
7/11/05 at 1:08pm
Quote:
Originally Posted by walk View Post

Yes but the fields are combined at viewing time (either by a de-interlacer if you're one of the lucky.. er... rich people to have a 1080p panel display, or by persistence of vision) so the effective resolution is 1920x1080.

The real issue it seems you wanted to point out is whether 1920x1080i (either through deinterlacing of phosphor persistence) is more appealing than 1280x720p. This is a classic 1080i vs 720p discussion and there are plenty of people in both camps.

The original claim that 1080i takes twice the transmission bandwidth of 720p is clearly not correct and that is what drew the strong responses.
post #6918 of 14496
7/11/05 at 2:32pm
Quote:
Originally Posted by walk View Post

Yes but the fields are combined at viewing time (either by a de-interlacer if you're one of the lucky.. er... rich people to have a 1080p panel display, or by persistence of vision) so the effective resolution is 1920x1080. The horizontal resolution is higher regardless (1920 vs 1280) and even though my CRT probably only resolves about 1600 of those I can still tell a difference. It's not hard to see, watching the Giants games on FSN/InHD (1080i) vs ESPN (720p, well mastered, looks decent but a little softer) or FOX (720p, not well mastered, quite blurry actually). I mean they use the same cameras..

I agree that baseball games are a great example of 1080i looking much better than 720p. It was obvious on my sony wega HD-36" direct view set and on now on my 42" panny plasma display. The actual resolution on my panny is 1024x768 so you would think the 720p would like just as good but it's not even a contest. When a game is on ESPN and INHD at the same time, it looks much better on the INHD channel. When the games are on FOX they look terrible, even when they claim to be in "hd". On fox, unlike the other channels, I get to use my TV's internal tuner to watch them in true 720p. Still no dice. My best bet is that the frame sizes are not exactly what they claim to be.
post #6919 of 14496
7/11/05 at 2:54pm
Quote:
Originally Posted by Xaque View Post

When the games are on FOX they look terrible, even when they claim to be in "hd". On fox, unlike the other channels, I get to use my TV's internal tuner to watch them in true 720p. Still no dice.

When you say FOX, I assume you're talking about KTVU, as FOX network hasn't done any HD baseball games yet this year, AFAIK, the All Star game will be the first.
post #6920 of 14496
7/11/05 at 4:55pm
are all the digital channels encrypted now on comcast in the bay area...i was hoping to use my qam turner on my sony grand wega so i don't have to get another digital cable box from comcast.
post #6921 of 14496
7/11/05 at 5:15pm
Quote:
Originally Posted by junglyboy View Post

are all the digital channels encrypted now on comcast in the bay area...i was hoping to use my qam turner on my sony grand wega so i don't have to get another digital cable box from comcast.

No, the local HD channels are not encrypted or their digital sub-channels. In some areas Discovery-HD and ESPN-HD are not encrypted either.
post #6922 of 14496
7/11/05 at 5:25pm
I'm noticing that Phase 3 of the 64/264 QAM transition hasn't happened yet in Rohnert Park. They've got a couple of days to meet their deadline. I wonder if there is a problem.
post #6923 of 14496
7/11/05 at 9:38pm
Real bad breakup Monday night, around 9:30 PM, on all channels in Cupertino.

Audio stuttering, constant blocking. Unwatchable.

Not sure if it was a problem all night or just around the time I tuned in.
post #6924 of 14496
7/12/05 at 1:07am
I've been getting a lot of channel available shortly messages, and some of my recordings have been an unwatchable pixelated mess, the last 2 recordings of Six Feet Under were trashed. I haven't been too worried about it as there really hasn't been much to watch and I figured they were messing around with the system. It would seem as if it's a signal strength problem as I'm getting massive error counts.

Anyone else in Santa Rosa having these problems..? Comcast is usually at such a loss when trying to fix these sort of problems I was hoping it would just go away..but my annoyance level is about to trip a breaker...
post #6925 of 14496
7/12/05 at 3:25am
Well I hope Comcast resolves the problem quicker for you guys than they did for me. For once my area has good HD channels. With my problem it wasn't until the HSI users started complaing that they bumped the priority. Had 3 weeks of the pixelating audio dropping mess on all QAM256 channels except ABC/707. I naively thought if I just let it sit, it would fix itself, resulting in an extra week of pixelation. I suggest you call it in and complain, since there are so few HD users (relatively) that they probably have no idea it's affecting multiple people. They'll spend a week just to determine it isn't a problem local to your home (which is always there initial assumption) and that just adds delays to getting the real problem fixed.
post #6926 of 14496
7/12/05 at 10:08am
Quote:
Originally Posted by bobby94928 View Post

I'm noticing that Phase 3 of the 64/264 QAM transition hasn't happened yet in Rohnert Park. They've got a couple of days to meet their deadline. I wonder if there is a problem.

There was a message on my 6412 box this morning that Comcast was going to be working on the system on 7/14/2005. So if you experience any problems this is the reason. I assume this is phase 3.
post #6927 of 14496
7/12/05 at 10:43am
Quote:
Originally Posted by sfhub View Post

I suggest you call it in and complain, since there are so few HD users (relatively) that they probably have no idea it's affecting multiple people. They'll spend a week just to determine it isn't a problem local to your home (which is always there initial assumption) and that just adds delays to getting the real problem fixed.

I called this morning about the audio-drops & pixel-flickering on ESPN-HD 723. It's been happening for about a week here. Her 1st response was to refresh my box. Then she said that if that doesn't work (and it didn't), then they may need to send a technician over. So it doesn't seem like my individual phone call is prompting Comcast to look into anything on their end. Just out of curiosity, is there a charge when a technician comes to your house for a problem like this?
post #6928 of 14496
7/12/05 at 10:43am
Quote:
Originally Posted by sfhub View Post

Well I hope Comcast resolves the problem quicker for you guys than they did for me.

So what I described rings a bell..? I really hate calling these people, given a choice, I think I would rather chew on glass shards..
post #6929 of 14496
7/12/05 at 10:45am
Quote:
Originally Posted by heyjjjaded View Post

I called this morning about the audio-drops & pixel-flickering on ESPN-HD 723. It's been happening for about a week here. Her 1st response was to refresh my box. Then she said that if that doesn't work (and it didn't), then they may need to send a technician over. So it doesn't seem like my individual phone call is prompting Comcast to look into anything on their end. Just out of curiosity, is there a charge when a technician comes to your house for a problem like this?

I was told once before that they will not really do anything until there are 3 calls received regarding the same issue...no, there is no charge for them to come out when there is a problem..
post #6930 of 14496
7/12/05 at 10:52am
Quote:
Originally Posted by cavaniws View Post

There was a message on my 6412 box this morning that Comcast was going to be working on the system on 7/14/2005. So if you experience any problems this is the reason. I assume this is phase 3.


I that same messag on my box 3 weeks ago. Phase 2 was already complete, so I am assuming that the latest would be Phase 3. I have that same message again this AM except that it is 7-14, so I guess they got slowed down and will begin Phase 3 now.
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