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Discussion Starter #1
What's going to happen after the change over date?

Stations will broadcast their signals in Digital, some BDU's will see it as a HD or Widescreen feed, but with a 4:3 SD signal being transmitted inside it, and the entire frame will be downconvert that to Analog and since its done for the SD cable subscribers, satellite dish subscribers, it will be letterboxed again?
 

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I believe the correct way for a BDU to convert HD to SD is to simply crop the sides of the picture. That is what most US broadcasters did when they had simultaneous transmitters. Most TV shows are produced without important information in the outside edges so it works OK. That doesn't work as well for movies but there is always the HD channel for people who care about it.
 

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I believe the correct way for a BDU to convert HD to SD is to simply crop the sides of the picture. That is what most US broadcasters did when they had simultaneous transmitters. Most TV shows are produced without important information in the outside edges so it works OK. That doesn't work as well for movies but there is always the HD channel for people who care about it.
I fear that you are right I hate this since it means that about a decade after the launch of HD (and almost 9 years since I bought my frist HDTV) that we are still not seeing the benefit of a 16:9 aspect ratio. When will that change?
 

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What's going to happen after the change over date?

Stations will broadcast their signals in Digital, some BDU's will see it as a HD or Widescreen feed, but with a 4:3 SD signal being transmitted inside it, and the entire frame will be downconvert that to Analog and since its done for the SD cable subscribers, satellite dish subscribers, it will be letterboxed again?
I don't expect anything to happen. The stations will continue to generate an SD 4:3 signal for the BDUs. Major BDUs get direct feeds from the stations by fibre or satellite so ending analog transmission will have no effect. Some smaller cable systems may have to convert HD to SD but if the AFD protocol is used the downconverter will switch between 4:3 and letterbox depending on the program content.
 

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Discussion Starter #5
i have a funny feeling this might not be the case.

I stayed in Ottawa one night, and watched some TV in the hotel. They had analog tv and showed what I believed was a Toronto Station. The show was an HD broadcast, but was downconverted to SD and hand black bars on the top/bottom. To top it off, the program also had added black bars on the sides of certain parts of the program at various times, making it a pillarboxed 4:3 image, was really weird
 

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^^^^
What's really weird is when you see bars on all 4 sides on a HD signal. I've seen some ads broadcast that way and also some shows. The History Channel seems to like doing that.

What's the point of going to the trouble of having a HD signal and then shrinking a 16:9 show so that it has bars all around?
 

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They are simply showing the WS SD content upconverted as intended in the original aspect, rather than zooming it. Lots of channels do this. I prefer this. If you wish to zoom it, do so on your TV or STB - sometimes this WS content is not exactly 16:9, so if they zoomed it, you may miss content, etc..
 

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The problem with pillarboxing and NTSC is that it reduces the picture quality dramatically. Zooming a pillarboxed image will result in a very low quality picture. Letterboxing HD over NTSC is bad enough but pillarboxed HD material on an NTSC channel is about as bad as it gets.
 

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Discussion Starter #9
on an HDTV you can use the zoom, but on an SDTV you can't quite do that, bad enough if the picture screen is a 21" to 24" and the image is the size of a 18" to 21" window within this image. Try reading the on-screen text, its quite difficult at that size.
 

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They are simply showing the WS SD content upconverted as intended in the original aspect
The original content is 16:9 and I'm watching on a HD channel. I certainly can understand letterboxing on a SD channel, but not on HD, where it results in bars on all 4 sides and poor resolution. If they can't be bothered showing a program properly on a HD channel, then I can't be bothered watching that channel when they do that.
 

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Discussion Starter #11
if the content on the HD channel is SD so its got side bars, but the station is downconverted to SD for broadcast to SD viewers with 4:3 tv sets, that is how the black bars are added to all 4 sides of the SDTV. who decides if the downconvert is cropped or mated with black bars? the BDU? I noticed there is a big inconsistancy among shows/channels for this.
 

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If they can't be bothered showing a program properly on a HD channel, then I can't be bothered watching that channel when they do that.
But they are showing the content perfectly properly. The original signal is not HD, it's SD, hence the bars on the sides. Since it's WS SD, there are then bars top and bottom also.

Watching in this manner preserves the original content, the original aspect, etc all upconverted on an HD channel. As stated earlier, if you then want to fill your screen with a zoomed picture (which will enhance all the inadequacies of the original SD programme) feel free, but allow the rest of us the choice.

It's like the Black Bars comments on DVDs. Leave it OAR thanks and let the viewer decide.

If the original programme were exactly 16:9, then perhaps the broadcaster could do the zooming and that may result in an adequate image, but often the enlarged image is almost torture to watch.
 

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^^^^
The History Channel has HD & SD channels available. On their HD channel, they have programs, including movies shown in letterbox in pillars. The original content is in 16:9 or wider format. If it's still only SD 16:9, then show it that way. By letterboxing and then adding pillars, they are forcing it to use only a small portion of the screen and it looks terrible. Why not properly convert 480 line 16:9 shows to 1080 (or 720) 16:9, instead of bars all around? Also, I have a hard time believing movies are available in SD only, particularly when that same movie is available on Blu-ray in HD. However, again, if they are, at least show them full screen. I'd much rather watch 480 line 16:9 than 360 line 16:9, whether zoomed or not. By forcing into letterbox, on a HD channel, they are throwing away 1/4 of the vertical resolution.

BTW, there have been a few times I've recorded movies on the History Channel, only to find them butchered in this manner. If possible, I'll then try to find that movie on DVD or Blu-ray, where I can properly watch it on the full TV screen. Further, at the beginning of the movies they have Ann Medina talking about the movie. She's in a 16:9 image, but due to being placed in that 360 line letterbox & pillars frame, there are a lot of video artifacts floating around the image that almost make it painful to watch. The video quality of those segments is horrible.
 

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Discussion Starter #14
JamesK, i agree with what you are saying. Recently a family friend of mine appeared on a TV show. The footage was recorded in 16x9, you could even see the cameras they were using. Now the program aired on an SD channel, so naturally, it was matted letterbox. The program also aired on a sister affiliate of the SD channel which is an HD station at a later time. Guess how the HD station handled the content? yup you guessed it, they pillarboxed it. I KNOW the content is in 16x9 I SAW the recorded content with my own eyes captured in 16x9, so why would they pillarbox it on an HD channel? that makes NO SENSE at all. even if its only recorded in SD quality, they should still be able to play it back full frame.
 

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^^^^
I've noticed both the CBC and CITY news still use SD cameras in 16:9 format. You can definitely see the reduction in resolution, but it looks much better than pillars & letterbox. I've also seen some segments on the news and elsewhere, where they obviously took a 4:3 source and cut the top and bottom off, to fit a 16:9 frame. This is just as bad, because you're now losing content.
 

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I'd much rather watch 480 line 16:9 than 360 line 16:9, whether zoomed or not. By forcing into letterbox, on a HD channel, they are throwing away 1/4 of the vertical resolution.
This is simply not true. The HD channel upconverts the original programme (whatever it may be) to 720P or 1080i depending on what they "broadcast". Your TV then displays the programme in it's native format, be it 768P, 1080P (or 1080i for CRTs). There is no "360".

http://www.digitalhome.ca/forum/showthread.php?t=73528

Take a look at an identical movie on the SD and HD channels of say TCM and you'll see that the end result after it's zoomed by the affiliate is very similar to the end result if you zoom it on your TV. I've done this with TCM several times since their HD channel currently upconverts SD movies in Canada and doesn't air true HD (yet).

I understand where you're coming from, however, there are instances where the aspect ratio will not fit properly if the affiliate zooms the picture (as you mention) and therefore I'd like to see OAR and be given the choice, just like with non-anamorphic DVDs - I can choose to watch windowboxed or zoomed or with my OPPO, I have the option of several different stages of zoom. I want the right to make that choice myself, not by someone else.

In the case of the news where they use WS cameras, if they zoom that to fill the screen I have no issues with it since the OAR is intact. I believe you are assuming that all WS programming is 16:9, when in fact it is not. I've seen aspect ratios from 1.5 all the way to 2.6, although most is around 1.6-2.0 - try measuring it yourself in the windowboxed format if you don't believe me - it won't all be 1.78:1.
 

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^^^^
In previous messages, you said:

They are simply showing the WS SD content upconverted as intended in the original aspect
and

The original signal is not HD
If they're showing 16:9 content in a 4:3 frame, the bars take up 1/4 of the 480 lines available which means only 360 are left for the image. When converted to HD, each of those lines will occupy 2 lines of 720 or 3 lines of 1080. But since you can't increase the effective resolution beyond 360 lines, that's all you see on the HD screen. On the other hand, if that 16:9 picture were transmitted without bars, it would fill the entire display at no worse than 480 lines. Regardless, all that black space represents lost resolution. As an experiment, try finding some show that's available on DVD in both letterbox & pillars and widescreen versions and compare the picture quality. In both versions, the DVD is delivering 480 lines, but on the letterbox, only 360 lines contain image data.
 

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If they're showing 16:9 content in a 4:3 frame, the bars take up 1/4 of the 480 lines available which means only 360 are left
You're making assumptions again. The original material could be 480i WS SD (just like your news example) which would use all the 480 lines, so 360 doesn't come into play unless they "downconvert" the content first, which makes no sense.

Granted, that may be what they do for the SD channel if they decide to show letterbox on the SD channel instead of cropped, however, the HD channel can be a totally different ballgame and the signal doesn't come from the SD downconvert, it can come from the original material.

In both versions, the DVD is delivering 480 lines, but on the letterbox, only 360 lines contain image data.
That would be true for non-anamorphic DVDs, but not true for anamorphic - see the FAQ below. Just as an FYI (I realize you were just giving an example), DVDs are a consumer format and broadcasters use tape (mostly). They cannot use DVDs, so they go to the "original" material, which could be a 480i WS master.

http://www.digitalhome.ca/forum/showthread.php?t=76070
 

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^^^^
The 360 lines comes from the amout of display area used by the letterbox format. If you have bars, top and bottom, the space they occupy is taken from the 480 of the full height SD display. So, any 16:9 picture on a SD channel has only 360 usable lines. There is no way around that, because the bars take up the other 120. Also, who said anything about anamorphic? I was talking strictly about the number of horizontal lines available (vertical resolution). Horizontal resolution is a whole other issue that's also affected by letterbox.
 

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You don't seem to understand that the black bars that are on your TV for SD programming do not have to take up "vertical space" on the original material. You don't seem to understand anamorphic either (check out the link I provided), which means that none of the original resolution is lost. Perhaps someone else can use different words to help you understand.

The only time there are 360 lines is if a DVD is non-anamorphic, or after a signal has been downconverted for SD transmission, or if the original tape is not WS, but 4:3, which is not the topic of this discussion.
 
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