Why isn't TV sent as 16:9 shown as 16:9?

[lobosrul]

You're not doing anything wrong, and your equipment works fine. Unlike Europe, there are no 16:9 analog broadcasts in the US. Theres 16:9 content in 4:3 channels. Yes its frustrating and annoying that the US is essentially behind a large chunk of the world in that aspect; the digital switchover in February should help out though.

[stanger89]

Originally Posted by lobosrul

You're not doing anything wrong, and your equipment works fine. Unlike Europe, there are no 16:9 analog broadcasts in the US. Theres 16:9 content in 4:3 channels.

But shouldn't those be stretched (vertically) in the same timings? Thus recorded stretched? I wouldn't expect the PVR to letterbox before encoding.

[lobosrul]

Originally Posted by stanger89

But shouldn't those be stretched (vertically) in the same timings? Thus recorded stretched? I wouldn't expect the PVR to letterbox before encoding.

I'm not 100% sure what you mean by that. But in at least some European countries their SD channels are sent 720x576 and somewhere in the signal it tells the TV to stretch out to 1024x576 if its a widescreen program. Its called PAL+ if its an analog signal (I dont think that was ever used much), but its very common on their digital SD channels. Someone on avsforum told me virtually everything in the UK is now anamorphic widescreen SD (except BBC-HD obviously) and has been since around 2003.

Theres no such mechanism in ATSC/NTSC. Apparently FOX use to (before switching to 720p) send an anamorphic (720x480) digital channel that the viewer would then need to set his TV to either stretch for widescreen or compress if it was a 4x3 show. But no other broadcaster has ever done this. Its either a 4x3 show, a 16x9 show with black bars at the top and bottom on a 4x3 channel, or HDTV. Or of course theres the really ugly 16x9 SD content on an HD channel where you have black borders on all 4 sides, like how KOB-DT broadcast Conan O'brien last night (I hate them BTW, theyre screw-ups).

As a complete tangent, there is a mechanism built in (or an add-on?) to ATSC that allows a 4x3 TV viewer to automatically have the widescreen HD signal either cropped to 4x3, or letter boxed in 16x9 depending on whether that program was 4x3 safe or not. It probably will never have widespread support though, and would just be something else for the local affiliate to screw up. Theres a post somewhere on avsforum concerning it.

[stanger89]

Originally Posted by lobosrul

I'm not 100% sure what you mean by that. But in at least some European countries their SD channels are sent 720x576 and somewhere in the signal it tells the TV to stretch out to 1024x576 if its a widescreen program.

Yeah, anamorphic 16x9, that was my guess. What I mean is the PVRs are "stupid", I don't think they have any scaling or resizing capability, so that would mean they should record the anamorphic video, thinking it was "normal", with no black bars.

So I don't really see how the PVR could record a letterboxed file from such a feed.

Its called PAL+ if its an analog signal (I dont think that was ever used much), but its very common on their digital SD channels.

Yeah, digital is easy, but we're not talking digital because we're talking about a PVR-USB2.

Someone on avsforum told me virtually everything in the UK is now anamorphic widescreen SD (except BBC-HD obviously) and has been since around 2003.

Theres no such mechanism in ATSC/NTSC. Apparently FOX use to (before switching to 720p) send an anamorphic (720x480) digital channel that the viewer would then need to set his TV to either stretch for widescreen or compress if it was a 4x3 show. But no other broadcaster has ever done this. Its either a 4x3 show, a 16x9 show with black bars at the top and bottom on a 4x3 channel, or HDTV.

Actually, ATSC supports anamorphic widescreen SD, but nobody uses it.

[lobosrul]

Originally Posted by stanger89

Actually, ATSC supports anamorphic widescreen SD, but nobody uses it.

ATSC supports 720x480p/i (720x576p/i as well actually, who knew). When broadcasting 16x9, the channel can fill that entire area up with a picture or throw in letterbox bars. The problem is that there is no mechanism to tell the PVR or TV to stretch that content out. The TV viewer has to realize that they need to press a button and "unsqueeze" (force widescreen) the picture. FOX-DTV used to do just that until switching to 720p (in '04 I think). DVD players have the ability to do this, OTA and cable does not.

W/o devices automatically displaying the video properly, I can hardly imagine the number of complaints there would be from "Joe schmo" average consumers that something is wrong with their TV.

Originally Posted by stanger89

Yeah, anamorphic 16x9, that was my guess. What I mean is the PVRs are "stupid", I don't think they have any scaling or resizing capability, so that would mean they should record the anamorphic video, thinking it was "normal", with no black bars.

But, the video coming in has black bars hardcoded into the picture (if your talking about NTSC/ATSC I wouldn't expect a set top DVR or a TV to realize that it needs to zoom in on a 16x9 TV automatically. Now a program like Showanalyzer could tell that indeed its 16x9 material contained in a 4x3 picture and pass that info on to SageTV and SageTV could zoom in by default.

Originally Posted by stanger89

So I don't really see how the PVR could record a letterboxed file from such a feed.

Theres a bit in the stream somewhere in 576 line DTV countries (PAL is really an anachronism in this case, but the term is used) that tells recording devices, and TV's when to stretch the anamorphic signal or not.

[stanger89]

Originally Posted by lobosrul

ATSC supports 720x480p/i (720x576p/i as well actually, who knew). When broadcasting 16x9, the channel can fill that entire area up with a picture or throw in letterbox bars. The problem is that there is no mechanism to tell the PVR or TV to stretch that content out.

ATSC A/53 Part 4 Table 6.2 lists the supported resolutions and format constraints, including, 704x480, 16x9 display aspect ratio.

Course, as noted the point is moot since nobody uses it. ATSC actually supports (if IIRC) 18 different formats, not just the 4 that are actually used.

But, the video coming in has black bars hardcoded into the picture (if your talking about NTSC/ATSC I wouldn't expect a set top DVR or a TV to realize that it needs to zoom in on a 16x9 TV automatically. Now a program like Showanalyzer could tell that indeed its 16x9 material contained in a 4x3 picture and pass that info on to SageTV and SageTV could zoom in by default.

Agreed, but the OP is stating that his TV automatically displays 16x9 without bars, that indicates to me, that his 16x9 source doesn't have bars coded in it.

Theres a bit in the stream somewhere in 576 line DTV countries (PAL is really an anachronism in this case, but the term is used) that tells recording devices, and TV's when to stretch the anamorphic signal or not.

Yes, exactly, the problem is, that means that all 576 lines are active, thus the PVR-USB2 should be recording no bars, but the OP is getting bars, so there's something I'm missing. I really don't think the PVR USB2 is adding the bars.

[KrisAcker]

Originally Posted by stanger89

Yes, exactly, the problem is, that means that all 576 lines are active, thus the PVR-USB2 should be recording no bars, but the OP is getting bars, so there's something I'm missing. I really don't think the PVR USB2 is adding the bars.

What your missing is that PALplus looks like any other analog PAL broadcast to any PAL receiver that doesn't know about PALplus. When 16/9 content is broadcast, a non-PALplus aware receiver will show a 16/9 letterbox. A PALplus aware receiver will detect the WSS (Wide Screen Signaling) in the VBI and zoom in into the 16/9 letterbox. The WSS can actually also tell the receiver that it's an anamorph 16/9 broadcast, but I've never seen that used.

The cheaper tv sets use line interpolation to get back to 576 lines from the letterbox or don't bother at all to increase the lines, the expensive ones come with a PALplus decoder that recreates the lines required to get back to 576 from the lines that make up the black bars. When the contrast is high enough (bright face surrounded by a dark background), you can actually tell there is something there in the black bars.

I hope I remember all that correctly. It was explained to me when PALplus broadcasts started in Belgium years back. To watch these broadcasts in SageTV, I have the Fill aspect ratio set to a vertical strech of 135 on my 16/9 screens.

[stanger89]

Originally Posted by KrisAcker

What your missing is that PALplus looks like any other analog PAL broadcast to any PAL receiver that doesn't know about PALplus. When 16/9 content is broadcast, a non-PALplus aware receiver will show a 16/9 letterbox. A PALplus aware receiver will detect the WSS (Wide Screen Signaling) in the VBI and zoom in into the 16/9 letterbox. The WSS can actually also tell the receiver that it's an anamorph 16/9 broadcast, but I've never seen that used.

Thanks, that's the concise explanation I was looking for, and explains what the OP is seeing. I was (sorta) hung up on why there'd bother being signaling for non-anamorphic widescreen.

[Moskus]

Originally Posted by lobosrul

You're not doing anything wrong, and your equipment works fine. Unlike Europe, there are no 16:9 analog broadcasts in the US. Theres 16:9 content in 4:3 channels. Yes its frustrating and annoying that the US is essentially behind a large chunk of the world in that aspect; the digital switchover in February should help out though.

That is very interessting, because I don't live in US, I live in Norway.
Guess I have to update my contact info...

But it looks like my "problem" fits your description.



Stanger69, thanks for your help. Zooming does the trick!

Now, if SageTV had an option to set different Aspect Ratio settings AND zoom settings at the same time (perhaps from a user defined preset list), it would be GREAT!

[stanger89]

The 4 AR modes were enough for me to handle pretty much everything I ran into, including letterboxed 16x9. I think if you setup your AR modes like I describe in that post, then it should cover you, and if you use the Auto Aspect Ratio Switcher, you'll hardly ever have to change anything manually.

[lobosrul]

Originally Posted by Moskus

That is very interessting, because I don't live in US, I live in Norway.
Guess I have to update my contact info...

But it looks like my "problem" fits your description.

LOL, sorry for some reason I read your original post as that everything worked fine in Norway, then you moved to the US.

[Moskus]

Originally Posted by stanger89

if you use the Auto Aspect Ratio Switcher, you'll hardly ever have to change anything manually.

This sounds great!

However, I'm not able to find the import, just lots of references to it. Anybody got a direct link?

[GKusnick]

http://forums.sagetv.com/forums/down...?do=file&id=28

[aclarke]

Originally Posted by GKusnick

http://forums.sagetv.com/forums/down...?do=file&id=28

This looks really useful and is a great start. Thanks for pointing it out as I'll be able to make use of it as well.

I recently set up SageTV again after buying my first 16:9 HDTV a few months ago. What I think would be really useful is a programme to postprocess videos to identify and remove letter- and pillarboxing. I've done some searching and I don't think this exists.

I've been using the "Auto" aspect ratio for the last couple days in SageTV but it has a couple limitations.

It seems to just look at the beginning of the show to determine the aspect ratio. The problem seems to be that my provider, Star Choice, puts 16:9 content into a letterboxed 4:3 screen on SD channels. Then for the first few seconds after a channel change, my receiver puts a channel overlay across the whole 16:9 size of the TV, so SageTV looks at the banner and thinks, "Oh, 16:9 format" and my show shows up windowboxed.

If I temporarily switch inputs, or open a show that's already in progress, the fill mode will stretch this content horizontally, basically taking the 16:9 content with windowboxes recorded to turn it into 4:3, and stretches it out to make it 16:9 again, so everything's fat and squished with windowboxes still in place.

If I had a programme to postprocess this content and remove the bars (and if I can change how my receiver box works to remove the channel banner) then when I open a programme it will automatically be the right aspect ratio and as large as it can be on my screen.

Does anyone know if a processor like this exists anywhere?

Thanks,
- Andrew.

[stanger89]

Sage isn't that smart, it just looks at the aspect ratio flags in the recordings. If they're SD (and not a DVD) that means they're 4:3 and Sage displays them as such.

Oh, and there's no way to remove the bars without reencoding.

[aclarke]

Can the aspect ratio flag for a recording change? For instance, the first 10 seconds be one aspect ratio and the next 5 minutes be another?

I know it's impossible to remove the bars without re-encoding. Is there a tool that can detect the bars and re-encode?

Of course, a plugin of some sort that could just find the location of the video and the bars and pass information to SageTV that would zoom intelligently and remove the bars would be even better ... maybe I should write that in my "spare time". That would get me back to my question though about whether there's already a tool out there that can detect the locations of window- and pillar-boxing.

- Andrew.

[stanger89]

Originally Posted by aclarke

Can the aspect ratio flag for a recording change? For instance, the first 10 seconds be one aspect ratio and the next 5 minutes be another?

What are you using to capture? AFAIK all the SD capture devices only record 4:3.

I know it's impossible to remove the bars without re-encoding. Is there a tool that can detect the bars and re-encode?

You can build AVIsynth scripts with the Autocrop plugin, not sure how you'd automate it exactly though.

Of course, a plugin of some sort that could just find the location of the video and the bars and pass information to SageTV that would zoom intelligently and remove the bars would be even better ... maybe I should write that in my "spare time". That would get me back to my question though about whether there's already a tool out there that can detect the locations of window- and pillar-boxing.

I believe ShowAnalyzer will dump the aspect ratio into it's output files, you could write a plugin to read that and set the AR appropriately.