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Discussion Starter #1
Sorry if this is a noob question, not the right place to ask or has been discussed before. Just wanted to ask regarding Bluray/HD 2:35:1 ratio films when playing on fixed LCD display. Are films that are this type of widescreen ratio really a 1920 *1080 resolution when you have black bars on the top and bottom ? Do the black bars count as part of the resolution or only the picture. It just occured to me that an lcd is a fixed display so the black bars is part of the overall resolution and is maybe 1/5 of the picture . So on 1080i LCD tv 2:35 films can't possibly be 1080i when having black bars maybe 820i instead . Is that correct?
 

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Quote:
Originally Posted by johngeno /forum/post/14232329


Sorry if this is a noob question, not the right place to ask or has been discussed before. Just wanted to ask regarding Blura/HD 2:35:1 ratio films when playing on fixed LCD display. Are films that are this type of widescreen ratio really a 1920 *1080 resolution when you have black bars on the top and bottom ? Do the black bars count as part of the resolution or only the picture. It just occured to me that an lcd is a fixed display so the black bars is part of the overall resolution and is maybe 1/5 of the picture . So on 1080i LCD tv 2:35 films can't possibly be 1080i when having black bars maybe 820i instead . Is that correct?

the black bars are part of the 1920x1080 equation.
 

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Discussion Starter #3
Thanks for the quick response. I was hoping that the picture is the 1080 res excluding the black bars . I guess just zooming on the movie would just degrade the picture quality. Not that I care much of the few pixels lost but it does not seem right especially over all this 1080i & 1080p debate . Come to think of it , 2:35 movies should take less disk space since the encoding would have less information.
 

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Discussion Starter #4
Quick follow question . Whats the math on that? Guessing if the black bars are 1/5 or more of 2:35 films then it is really 1536*864p resolution. Anyone now the actual length of the black bars?
 

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Quote:
Originally Posted by johngeno /forum/post/14232614


Quick follow question . Whats the math on that?

For 2.35:1 films:


1920/2.35=817 so approx 817 lines of moving pictures (817p sort of - but presented in a 1080p window)


1080-817=263 so approx 263 black lines


I say approx because they also can crop the frame again on the top and bottom so it is within a full macroblock height on top and bottom I think.


2.40:1 films (actually 2.39:1?) will obviously have more black lines.

Quote:
Come to think of it , 2:35 movies should take less disk space since the encoding would have less information.

I'd say that's probably correct, as encoding static black bars is a lot easier for the encoder than encoding moving video
 

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Unless I've worked it out wrong 2.35:1 HD movies should be 1920X817P


Edit: Yeah, what he said^^^ Lol!
 

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Discussion Starter #7
Guys , thanks for the info . The math ratio(1440*817p) suggest they are closer to 1280*720p standard . I guess 1080p res are only real for the 1:85, 1:77, etc format.
 

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Quote:
Originally Posted by johngeno /forum/post/14232953


Guys , thanks for the info . The math ratio suggest they are closer to 720p standard . I guess 1080p res are only real for the 1:85, 1:77, etc format.
Quote:
I guess 1080p res are only real for the 1:85, 1:77, etc format.

In my view they should really say on the packaging/spec list of 2.40:1 titles that the moving picture res is around 800 lines (800p), and a similar thing for 2.35:1 movies
Quote:
The math ratio suggest they are closer to 720p standard .

But I think the 720p standard though is something like 1280x720p (and that's for 1.78:1 content - it too would be a lower pixel res with 2.35 & 2.40:1 content I think).


Maybe titles should specify the pixel width and height of the moving picture area so it is more clear to customers (as calling all Blu-ray movies 1080p probably isn't very accurate).
 

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Quote:
Originally Posted by johngeno /forum/post/14232953


Guys , thanks for the info . The math ratio(1440*817p) suggest they are closer to 1280*720p standard

It's not 1440*817 though.

It's 1920x817 for 2.35:1 movies, and around 1920x800 if it was 2.40:1 (or a few more lines if 2.39:1)


On current encoded Blu-ray titles, you only have less than 1920 pixels in width used (non-black) if the aspect ratio of the movie was something like 1.33:1 or 1.37:1 etc. (though 1.78:1 Planet Earth was partially recorded on 1440x1080i video cameras, but will have been upscaled for release to 1920x1080).
 

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Discussion Starter #11
JoeBloggs, your right . The width 1920 is unaffected while the length is trucated by the black bars like you said . I made the mistake of dividing both width and length of the resolution.
 

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Quote:
Originally Posted by Joe Bloggs /forum/post/14232982


In my view they should really say on the packaging/spec list of 2.40:1 titles that the moving picture res is around 800 lines (800p), and a similar thing for 2.35:1 movies

Why? They don't on DVDs. The percentage wasted on black space is the same as with anamorphic DVDs.
 

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Quote:
Originally Posted by johngeno /forum/post/14232495


Come to think of it , 2:35 movies should take less disk space since the encoding would have less information.

Not really, since you still want to maximize your encoding bitrate to take up all the space on the disc considering that you're throwing out something like 98% of the data from the original uncompressed frames.
 

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Quote:
Originally Posted by 42041 /forum/post/14233914


Not really, since you still want to maximize your encoding bitrate to take up all the space on the disc considering that you're throwing out something like 98% of the data from the original uncompressed frames.

Yes it will take whats left for it, but a 2,35:1 encode needs less disc space.


Its really 33% less frame to encode.
 

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Quote:
Originally Posted by nm88 /forum/post/14233871


Why? They don't on DVDs. The percentage wasted on black space is the same as with anamorphic DVDs.

Because on DVDs they don't claim that it is "Full 1080P High Definition" or that it is "Beyond High Definition". On SD-DVDs they don't claim that it is higher resolution than it actually is.
 

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Quote:
Originally Posted by Joe Bloggs /forum/post/14232982


In my view they should really say on the packaging/spec list of 2.40:1 titles that the moving picture res is around 800 lines (800p), and a similar thing for 2.35:1 movies (as calling all Blu-ray movies 1080p probably isn't very accurate).

I think this whole hi-def thing is confusing enough for most casual consumers (who appear not to be able to understand the difference between hi-def and upscaled DVD) that this is the last thing we need if some semblence of mass adoption is the goal.


Plus, what would a full 1080p encode of 2.35:1 movies do for most people anyhow? Although those of us with anamorphic lenses would benefit from this 'anamorphic encode', the vast majority would have their player 'letterbox' the film onto their 16x9 set and end up with no net gain (you could actually argue it would be worse since the player would be scaling 1080 down to 800-ish). Unless they, 'gasp' intended to watch 2.35:1 pan-and-scanned on their 16x9 set.
 

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I'll be honest with you ... I've become very weary of any inquiries in regard to aspect ratio. To me, all references to aspect ratio should be intuitively obvious. How many times, for instance, have you heard or seen people ask, "Why do I still see black bars?" I mean, how could you not see black bars sometimes?


The 1.78:1 aspect ratio was chosen partly because it was a compromise between conventional television (1.33) and widescreen cinema (2.35 or 2.40 or so). While 1.85 films fit almost exactly (and all native HDTV broadcasts do fit exactly, of course), lots of material is going to be inherently "too narrow" or "too wide." The fact that so many people (and I'm not referring to anyone on this thread, just in general) can't quickly grasp that just leaves me shaking my head. What's not obvious about it?


As for this particular thread, again, it should be apparent that the panel's resolution applies to the entire image, including whatever black bars there may or may not be. In the case of widescreen films, that's a price we pay to see the entire frame as the filmmakers intended, as it appeared in the theater, and that's very important to me.
 

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Quote:
Originally Posted by Mr. Brownstone /forum/post/14234830


As for this particular thread, again, it should be apparent that the panel's resolution applies to the entire image, including whatever black bars there may or may not be. In the case of widescreen films, that's a price we pay to see the entire frame as the filmmakers intended, as it appeared in the theater, and that's very important to me.

I'm not talking about the resolution of a panel (this thread was originally in the HD Media Software section), but the resolution advertised for 2.35:1 and 2.40:1 Blu-ray releases, which claim, on the front of the case "Maximum Hi-Def Experience", "FULL 1080P RESOLUTION" (in all caps in big text), yet on the back say, in tiny text "Presented in 2.35:1 Aspect Ratio".


Reviews for 2.40:1 Blu-ray movies say "Resolution: 1080p/24", and sites selling the disc advertise similar specs, despite the fact that, whatever size or resolution of TV anyone watches it on, or whatever type of projector someone has, it will never have 1080p worth of resolution for the actual motion picture (as the 1080p figure includes the black bars, which people aren't supposed to be watching). The actual motion picture (excluding the black bars) is encoded on the disc with only about 800 lines for 2.40:1 films.
 

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Quote:
Originally Posted by ca1ore /forum/post/14234740


I think this whole hi-def thing is confusing enough for most casual consumers (who appear not to be able to understand the difference between hi-def and upscaled DVD) that this is the last thing we need if some semblence of mass adoption is the goal.

Whether it confuses people or not, advertising actual resolutions of movies you are selling, especially where you are selling them on a new format where the main selling point is it's increased resolution, is better than false or misleading advertising. Honesty is the best policy.
Quote:
Plus, what would a full 1080p encode of 2.35:1 movies do for most people anyhow? Although those of us with anamorphic lenses would benefit from this 'anamorphic encode', the vast majority would have their player 'letterbox' the film onto their 16x9 set and end up with no net gain (you could actually argue it would be worse since the player would be scaling 1080 down to 800-ish). Unless they, 'gasp' intended to watch 2.35:1 pan-and-scanned on their 16x9 set.

What advantage were "1080p" movies when 99% of people watching them only had 720p (or 768 line) displays? It meant that when they upgraded their TV later on, they would have access to a higher resolution than could be displayed on their original TV.


Projectors with anamorphic lenses could also take advantage of this. And yes, if a user pressed a zoom button (if their player had zoom) to watch it in 1.78:1 pan-and scan
they could, and it would show that the disc actually had the increased resolution that was claimed. LCD (and other flat panel televisions) are getting better all the time, I'm sure higher res ones (maybe also ones with higher aspect ratios too, for people who want them) will be available to consumers soon, and even current res ones will probably be able to take advantage of the increase in resolution, even if all 1080 moving picture lines can't currently be displayed on screen at the same time (eg. it may help with current picture processing algorithms to have more line samples to work with).
 
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