Do Detailed HDTV Listings Exist?

nick_davison asks: "Having finally made the move to HDTV, I've been getting up to speed on the usual debates about HDTV (is 720 rows/frame better than 1080 served every other frame, 540 at a time? Is 1080i meaningless if all your signals are 720, and thus 1080 is just having to resample your image? Is 1080i and 720p meaningless if the digital signals bitrate is so low it's garbage anyway? etc). Trying to form my own opinions, I went looking for TV listings that would at least show the resolution of the signal (1080i or 720p) and, ideally, though I guess less likely, the bit rate. What I ended up with was, if I was lucky, TV listings that differentiated HD and non HD shows on HD channels but nothing more. Do such listings exist? Is this something the TV companies deliberately hide? Is there any way to even piece together this information?"

Comments

Per Network

[prothid]

It looks like it may vary per network and not per show?

http://alvyray.com/DigitalTV/Naming_Proposal.htm

Here in Austin...

[caperry]

I don't know about where you are, but here in Austin TX the resolutions are fixed by channel. For example, ABC, NBC, PBS, and WB all broadcast at either 480i or 1080i. The FOX affiliate broadcasts at 480i or 720p. These are OTA only. On the local cable company, everything except FOX and ESPN are upconverted to 1080i - why I don't know. I believe the reason is 1080 is a bigger number than 720 and thus must be better. Finally, everything HD on DirecTV is 720p. Bitrates vary (IMHO PBS usually having the best starting in the evening when they turn off the three other feeds they provide OTA) all the time. The best resource I've found has been the AV Science Forum which has a rather large listing of HDTV information for various cities.

Finally, to add some fuel to the 720p vs 1080i debate - IMHO: it's all about your output device. If your output device is any type of projection (including rear projection TVs) then p is always better than i simply because that's how your device draws the screen anyway. I could be wrong, but at least it seems that way to me.

Re:Here in Austin...

[angle_slam]

For example, ABC, NBC, PBS, and WB all broadcast at either 480i or 1080i. The FOX affiliate broadcasts at 480i or 720p.

You're right that resolutions are fixed by channel. (E.g., see here). The networks all either chose 720p or 1080i. However, in most areas of the country. ABC is 720p through most of the country, except some areas of Texas. See here

Regardless of the HDTV format being broadcast, all new HDTV receivers can receive both formats. New HDTV televisions will convert any received signal to a format that is compatible with your new display. The 720p format uses progressive scanning, which is just like your computer monitor. Progressive scan offers crystal clear images that virtually eliminates those scanning lines that are visible on most large screen televisions. ABC broadcasts all of its programming using the 720p format except in Dallas, where the ABC station broadcasts in 1080i. Many new flat panel displays use progressive scan

Re:Here in Austin...

[gatzke]

1080i is great for slow moving high res stuff, like landscapes and stuff on PBS.

720p is great for sports.

I personally want a 1080p native system before I move to HDTV. , or else I will feel that I am being down-sampled when I want 1080i. I feel much better about upsampling from 720p to 1080p.

Just read there are nice 1080p systems out there if you look. A couple of huge 46" flat screens are out for about $6000. The 1080p projectors are still about $20,000.

Re:Here in Austin...

[angle_slam]

The latest generation Samsung DLPs are 1080p. (For example, see this page.)

Re:Here in Austin...

[BushCheney08]

The problem is that there aren't any devices that output 1080p. Sure, your computer can do it, but that's about it at this point. Also, the bandwidth necessary for it is higher than the HDMI spec allows. So if any boxes do ever come out that output 1080p, they'll either use parallel HDMI outputs to do it, or another HDMI spec will need to be created.

Re:Here in Austin...

[schon]

1080i is 540 lines per screen, 720p is 720.

Yes, and 1080i is 1920 pixels per line, whereas 720p is 1280.

They're saving bandwidth.

Sorry, but WHAT?!!?!?! ?!?!

This is a broadcast or cable delivery, not an internet feed. The bandwidth is fixed, whether they use it or not.

Depends on the broadcaster

[the eric conspiracy]

Not easy - you have the resolution/compression the show was recorded in, and then the rez/comp the show was broadcast in. The first is nearly impossible to find out, and for the second you might find out res pretty easy, but comp or bandwidth or bit rate may well be a secret for competitve reasons. Satellite tends to have the worst compression, while cable is decent, and OTA might be the best.

Constant on a per-channel basis

[crow]

While, in theory, I don't see any reason that they can't change the resolution whenever they want to, currently every network broadcasts in exactly one format per channel.

Fox does everything in 720p. If it's not HD content, they upsample it to 720p (e.g., The Simpsons, advertising, etc.). CBS does 1080i. I'm not sure what PBS uses.

Personally, I wish they would use whatever is as close as possible to the original format. If it's a movie, then do 24 frames per second without interlacing, one frame per original film frame. Yes, the standards support that. If it's a European import, do 50 frames per second. If the ad is in low definition, use 480p.

Why be constant?

Re:Constant on a per-channel basis

[MaxQuordlepleen]

Not sure what their reason is, but the reason I would *hate* this if they did it is resolution switching. My projector takes a few seconds to change resolutions (think of a CRT monitor flickering when you change screen resolution). As it is when I change channels I have this effect, if it happened when going into / out of commercial, et cetera, it would be very irritating.

Re:Constant on a per-channel basis

[nick_davison]

My Sony XBR does the same thing.

For me, the solution was to pass it over to the cable box to handle. I can tell the cable box what inputs my TV accepts (480i, 480p, 720p, 1080i) and then it will only send in combinations of those modes. Accordingly, if I switch off everything but 1080i, everything gets upsampled (or, technically, kind of downsampled if a single frame of 720p vs. the 540 of 1080i) in the cable box without the flicker. The TV then never switches modes - it always gets a 1080i feed - and so no flicker.

The nerd part of me hates this solution. XBRs apparently resolve to something like 1400 scan lines. Thus I'm taking a signal, forcing it in to 1080i with the slight softening and disorting of a scaling algorithm and then doing it again to fit the TV's native 1400 lines. I'd much rather just do one rescale, in the TV, and have 720p politely just scale once, at roughly 2 lines per line of input, and stay really sharp. Sadly though, that brings the flicker.

Re:Constant on a per-channel basis

[JWSmythe]

    I know exactly what you mean. When I switch from DVD to DirecTV, it rescans the devices to find where the new input is coming from, even though the new input is exactly where the old input was. I have two signal cable run from my equipment over to my projector, but one is only for legacy equipment (PS2), and the SVideo (to the PS2) rarely used. It does the same thing on resolution changes, thinking the old device was detached.

Tuner Card if nothing else

[Anti_Climax]

My roommate's media computer has a HiPix DTV-200 HD Tuner, and the on screen display shows the video dimensions, bitrate, signal quality and HD Format. You might be able to use one of these if you can't find the listing info you're looking for. Though you might be able to get more info on AVSFourum.com rather than slashdot though. Best of luck to you

Early Adopter Blues

[Anonymous Coward]

Even though you write you "finally" switched to HD, you are still an early adopter. Early adopters almost always have the blues because they pay more to get less, but earlier. TV networks and other providers are still weighing how much of their bandwidth to use for what kind of digital broadcast. They can, I believe, divide their total bandwidth up however they like. Here (San Francisco) the Public TV station, KQED, is broadcasting five lower-bandwidth channels simultaneously, so each cannot be of the highest resolution.

But there are so few receivers/tuners in use that can make use of high-resolution (above 480i, I suspect) that such broadcasts are very hard to find, if they exist at all. And, of course, cable nor satellite carry true HD, the first startup all-digital network having already gone dark, IIRC. Following this logic, it is easy to see why newspapers and TV listings do not bother to mention the format of HD sources.

The market will determine the future -- within the limits set by the political/monopoliticial/economic games that are sure to be played as there is so much money potentially involved.

I know how you feel; I am impatient to set up a MythTV box; but I was impatient ten years ago for PVRs, and look how TiVOs have come down in price once the market discovered them (and humoungous hard disks became cheaper!)

Chill out and enjoy the lower-quality HD broadcasts and cablecasts that are currently available; you're way ahead of the game. You probly won't have to buy any video hardware for a long time to come....

TitanTV

[antdude]

TitanTV gives me details.

Examples in L.A. area:

Alias
The Horizon (New) 12/14/2005 10:00 PM, 1 hr
Syd is reunited with Vaughn after being kidnapped and hypnotized by a familiar face, who has a vested interest in her future---and in her unborn child.
Cast & Credits: Jennifer Garner, Ron Rifkin, Victor Garber, Michael Vartan, Carl Lumbly
Drama/Action
TV14, English, 2005
HDTV - presented in 720p (Dolby Digital)

--

The Late Show with David Letterman
  (New) 12/14/2005 11:35 PM, 1 hr
Stephen Colbert; a holiday toy demonstration.
Talk/Other
TVPG, English, 2005
HDTV - presented in 1080i

My take

[alexwcovington]

People buying HDTV sets today are very much early adopters, and with that comes the growing pains of new technology. There's no guarantee that the MPEG-2 implementation used by present ATSC tuners will even be the standard in a few years; broadcasters are lobbying for more efficient codecs, and even pay service OTA.

Bitrates?

[Trip Ericson]

There's really no way to deal with listing of bitrates, since the amount of bandwidth given to the stream varies by station.

For example, NBC29 (WVIR in Charlottesville, VA) dedicates the entire 19.393 MBPS to their NBC-1080i broadcast, while my local NBC station (WSLS in Roanoke, VA) reserves a small amount for a radar feed and serves the rest (in the neighborhood of 16.5 MBPS) to HDTV.

Further, some stations that broadcast more than one stream do what's called stat-muxing, short for Statistical Multiplexing. This means that when the HDTV feed needs the bandwidth, it is given to it and the other streams are cut down, then when it's not needed anymore, it is given to the subchannel, so there is NO set bitrate. This is done dynamically as it is transmitted, so in a high-motion scene it may draw 18 MBPS, but then change to a scene of someone sitting in a chair talking and drop to 12 or 13 MBPS.

Re:Bitrates?

[nick_davison]

I was curious as to whether or not there were any resources for finding out which stations do what - like your example of WVIR vs. WSLS.

Also I heard that DirectTV, at least in some markets, has dropped some of its 1080i signals from 1920x1080i to 1280x1080i with the excuse that most HDTVs only natively support 720p (downscaling 1080i as needed) and thus 1280 horizontal is sufficient and lets them compress further, fitting more channels on to a single transponder which, from what I have read, costs satelite companies a lot more to rent than it does cable companies.

I'd be fascinated to see a table like the one at http://www.widemovies.com/dtvtransponders.html that shows how given local cable and satelite providers divide up their feeds - were such a resource to exist.

Part of this is motivated from the story on WebWire about 50% of users thinking they're getting HD because they have an HD ready set but no means of receiving a signal, aren't connecting their HD Cable box with the right cables, are watching the 480i versions of the channels also shown in 1080i further through the channel lists, etc.

Call it the obsessive nerd thing but I'd like to get a better understanding of what I'm actually viewing and also a better understanding so I can give advice to friends when they ask "So, is HD worth it? Is it better to get DirectTV or Cable? Are 720p sets that much worse than 1080i?

From seeing *most* HD channels turn out to be 1080i, a 1080i set seems to make sense as most channels would need downsampling from 1080i to 720p whereas, the other way around, relatively few channels need upsampling from 720p to 1080i. That much I gained from finding resources like CNet's. Knowing the provider/bandwidth answers would help in picking the best services (cable vs. HD vs. over the air) to avoid compression artifacts.

Re:Bitrates?

[Trip Ericson]

Well, the rule is NORMALLY this:

1080i:
Everyone except ABC and Fox stations and other properties, such as ESPN.

720p:
ABC, Fox, ESPN. Dunno for sure about DirecTV, but it would make sense as they're owned by Fox.

Now there are exceptions, such as WVEC-13 (ABC) in Norfolk and WFAA-8 (ABC) in Dallas doing 1080i instead of 720p. All Belo stations are doing 1080i, even if they're ABC (they're upconverting it).

On the other hand, WHRO-15 (PBS) in Norfolk and WCBI-4 (CBS) in Tupelo, MS doing 720p instead of 1080i.

Most stations maximize the HD at the expense of the SD, so if you realize that an SD stream will survive with about 3MBPS, you should be able to figure the bitrates.

Now if you want to know what subchannels you have, if you're lucky enough to be near myself or a fellow in Minnesota I have helping me, I've set up a site ( http://www.rabbitears.info/ ) that I've been working on in my spare time. Otherwise, check http://www.avsforum.com/ and look for your market in the Local HDTV forum. Also, you could webmaster email at me rabbitears and dot I info could try to help you out, if you'll give me the city the stations you watch come from.

I honestly can't say I've seen a big difference between 720p and 1080i, though 720p is less likely to "pixelate" in high motion. I have a front-projector that has been well-calibrated and it does 720p, and that's the only thing I've noticed different about the two.

If you have any more questions, feel free.

Re:Bitrates?

[kesuki]

720p is less likely to "pixelate" in high motion.

There is the trick, what most people don't realize is that 1080i is actually only able to capture motion at 15 fps. because at 30 fps, 15 are the a frames, and 15 are the b frames. The reason Motion pictures worked so well with 24fps is because movies have alwys used a 'progressive' display technology.

There is also a 1080p format, but unless you pay as much on a tv set as a car, you won't be getting one of those (unless it's a PC monitor) anytime soon. Since almost nothing is shot in 1080p (except star wars, episode III) you won't be getting that much content unless you decide to pay as much as some people would spend on a house on a 1080p digital camera system.

Now I don't know this for certain, but i suspect that sporting events are actually shot at much higher than broadcast frame rates to facilitate the 'instant replay' they are usually showing them at 1/8th or 1/16th speed.. simply shooting at 60fps would double the quality of the 'instant' replay, if they aren't currently doing so. and thus now you know why all sporting events are fillmed in progressive scan, and why we as consumers should REJECT inferior 1080i native sets.

HD Sports Guide

[angle_slam]

If you're interested in sports, check out HD Sports Guide, which shows what sports are available in HD and in what resolution they will be aired.

HDTV Galaxy

[net_oholic]

HDTV Galaxy gives listings for shows being broadcast in HDTV, and gives the resolution. I find it to be fairly accurate.

Re:Beware of upscaling

[JWSmythe]

    I was talking to a friend, who now works for a major cable company. He said they dropped several of their HD channels, because the demand wasn't there. I was surprised, I thought they'd be turning more of them up, not bringing them down.

    I get more HD channels with DirecTV than his company supplies on cable. I'm not in his market (wrong side of the country), so his company's decisions don't matter much to me.

TV is about the lowest common denominator.

[Caspian]

Always has been. Always will be. Although at first, the TV was supposedly predicted to be a fantastic intellectual tool, bringing learning to the masses, in practice it has ALWAYS, by and large, been about Joe Beer. Period.

Joe Beer does not know what a "bitrate" is. Joe Beer does not know what "interlaced" means. Joe Beer probably doesn't even know what a "pixel" is.

Thus, what you want will probably never exist. At least, not officially. Some geeks might attempt to create such a resource, and may in fact get themselves sued by some very large corporations for doing so...

Per Network In Australia

[NerdENerd]

In Australia it is upto the network to decide what they broadcast in. We have 5 networks in my City and 4 broadcast in 1080i and one broadcasts in 576p. The 7 network calls one of its streams HD but i don't think 576p should be called HD as it is the same resolution as it SD channel only it is progressive rather than interlaced. The progressive channel definitely looks better than the interlaced channel. We don't get an 720p broadcasts at all. In fact not many of the PAL HD TV sets support 720p at all. HD has been a real pain for me as the only PC video cards that do HD component TV out only support NTSC and don't support PAL. Same with my Xbox, it does PAL SD only and NTSC HD. The only NTSC signals my TV supports are 480i and 480p.

Re:Beware of upscaling

[Lehk228]

meh HD is overrated for broadcast, unless a program was originally intended for HD you will end up seeing stuff you weren't supposed to, blemishes, wires for special effects, jaggies where the green screen didn't quite do it's job. for movies HD is great because theaters are already far higher quality and so you don't see random stuff that was supposed to be invisible to the viewer

a decent digital SD format would be a much better investment, rather than one channel running at 1080i or 720p we could have 2 to 4 channels running 320 by 240 interlaced. things like news and talk shows don't need super high resolution unless YOU want to see jerry springer's pimples.

personally i would rather have more options in what to watch than have the same options at higher resolution.

Re:Beware of upscaling

[JWSmythe]

    I agree totally. DirecTV added more channels, so they could have the duplicate of regular resolution and HD. It's kind of cool for me, since I do have HD, but a couple months ago, before I got the HD receiver, it was completely worthless to me.

    I have a big front projection screen, so having things in HD is actually very nice. Until I moved, I had my screen set for roughly 10 feet wide, and yes, I saw things that you weren't suppose to see. Reruns of sliders became even more cheesy, because I could see the really lame effects where they jumped through the wormhole, and the characters were actually just still shots squished and stretched. On a normal TV, I would have never noticed.

    For some reason, the HD DirecTV is noticable in the variations it has all the way up to 1080. I was trying to demonstrate the reason for "needing" the HD receiver to my girlfriend after we got it. I brought it down to 480, with it paused on a HD movie. As I stepped up, you could see the jagged edges go away, and details show up. The best example was in that shot. At 480, you could see the character's head. By the time we got up to 1080, you could see the whisps of his hair, which weren't visible at the lower resolutions.

    I know a few people have said on here that DirecTV only broadcasts at 720, but we couldn't see the hairs at 720.

    Now, do I *NEED* to see Jerry Springer's inbread guests nose hairs? Probably not. Does it make a clearer picture on a large format screen? Yes. If I had a smaller screen, it wouldn't have made a freakin' difference. I know on the large screen, it kills the magic of some things, but for many things it's much better.

    The one thing that sucks about my projector is that it doesn't see that something is letterboxed, and try to expand it out to the full screen size. My projector doesn't have a good enough zoom on it, to expand a letterbox out to the full screen size with the throw that I'm using now. I suppose in 10 years, that will be something I'll be looking for in a new projector, but everything will be different by then. :)