DVD aspect ratios widescreen TVs

Archived from groups: alt.tv.tech.hdtv (More info?)

"Bruiser" <noth@nks.com> wrote in message
news:LOidnVSYfvN6wKHcRVn-og@giganews.com...
> I'm a little confused with the whole aspect ratio of DVDs vis-a-vis
> widescreen TVs. My understanding is this:
>
> 1:85:1 = 16:9 (the entire screen is used for the image)
> 2:35:1 = anamorphic (there will be black bars on top/bottom)
>
> Yesterday I loaded up a movie which the box stated was "presented in
> widescreen, in original 1:85:1 aspect ratio, enhanced for 16:9
> televisions"
> and it had black bars on top/bottom. I don't understand why it was shown
> like that.
>
> And what exactly does "enhanced for 16:9 televisions" mean?


Actually 1.77:1 = 16:9 so there will be small black bars on material that is
1.85:1 but there are usually hidden in the overscan area of most direct view
and rear projection television.

Enhanced for 16:9 televisions lets you know that the DVD was authored in an
anamorphic fashion so that DVD players can be set for 16:9 displays and take
advantage of all of the available bits on the disc (for the given aspect
ratio) or be set for 4:3 displays thereby letterboxing the image and
retaining it's aspect ratio.

Charles Tomaras
Seattle, WA

Archived from groups: alt.tv.tech.hdtv (More info?)

"The Cooler." However, I just looked it up on IMDB and it states it is
2:35:1, which would explain things (the box, I'm absolutely positive, stated
1:85:1 -- it even had that diagram that shows how it will look on standard
vs. widescreen TVs).

Thanks to you and Charles for the clarifications.

B.

Rajendra Gondhalekar wrote:
>> Which movie was it? If the original aspect ratio was 1.85:1, then
>> there should have been no noticeable bars on a 16:9 TV as result of
>> typical overscan. If the original aspect ratio was 2.35, even a
>> movie enhanced for 16:9 television will be encoded with bars at the
>> top and bottom. What enhanced for 16:9, means that a 1.85:1 and
>> above movie is encoded anamorphically on the disc, and the DVD
>> player and the widescreen TV will stretch it appropriately. This
>> method of encoding provides more resolution to the TV than a non
>> anamorphic encoding.
>>
>> "Bruiser" <noth@nks.com> wrote in message
>> news:LOidnVSYfvN6wKHcRVn-og@giganews.com...
>>> I'm a little confused with the whole aspect ratio of DVDs vis-a-vis
>>> widescreen TVs. My understanding is this:
>>>
>>> 1:85:1 = 16:9 (the entire screen is used for the image)
>>> 2:35:1 = anamorphic (there will be black bars on top/bottom)
>>>
>>> Yesterday I loaded up a movie which the box stated was "presented in
>>> widescreen, in original 1:85:1 aspect ratio, enhanced for 16:9
>>> televisions"
>>> and it had black bars on top/bottom. I don't understand why it was
>>> shown like that.
>>>
>>> And what exactly does "enhanced for 16:9 televisions" mean?
>>>
>>> Thanks,
>>> Bruce

Archived from groups: alt.tv.tech.hdtv (More info?)

Matthew Vaughan wrote:
>> "Bruiser" <noth@nks.com> wrote in message
>> news:LOidnVSYfvN6wKHcRVn-og@giganews.com...
>>> I'm a little confused with the whole aspect ratio of DVDs vis-a-vis
>>> widescreen TVs. My understanding is this:
>>>
>>> 1:85:1 = 16:9 (the entire screen is used for the image)
>>
>> This isn't quite correct. 16:9 is 1.78:1, and has no direct
>> relationship to the common movie formats. It's just much closer than
>> 4:3 is, and happens to be very close to 1.85:1.
>>
>>> 2:35:1 = anamorphic (there will be black bars on top/bottom)
>>>
>>> Yesterday I loaded up a movie which the box stated was "presented in
>>> widescreen, in original 1:85:1 aspect ratio, enhanced for 16:9
>>> televisions"
>>> and it had black bars on top/bottom. I don't understand why it was
>>> shown like that.
>>>
>>> And what exactly does "enhanced for 16:9 televisions" mean?
>>
>> It means that the images are placed on the pixel format of the DVD
>> in a manner intended for display on a 16:9 monitor instead of 4:3.
>> In either case, there are 720 columns across in each of 480 lines.
>> On a standard 4:3 DVD, the pixels are intended to be 12.5% taller
>> than they are wide (which is how regular TV is set up). On an
>> "enhanced for 16:9" DVD they are intended to be 18.5% wider than
>> they are tall. If you watch a 4:3 DVD on a 16:9 TV, set to fill the
>> whole screen, it will appear to be stretched out horizontally. If
>> you watch a 16:9 DVD on a 4:3 TV, it will be compressed horizontally.
>>
>> A 4:3 letterboxed DVD provides approximately the following vertical
>> resolution for the two most common movie formats:
>>
>> 1:85:1 letterboxed: 346 lines, with 67-line black bars wasted above
>> below
>> 2.35:1 letterboxed: 272 lines, with 104-line black bars wasted above
>> and below
>>
>> An "enhanced for 16:9" DVD provides approximately the following
>> vertical resolution for those formats:
>>
>> 1:85:1 letterboxed: 460 lines, with 10-line black bars wasted above
>> and below (but due to overscan, many TVs won't even show the black
>> bars of the letterbox)
>> 2.35:1 letterboxed: 362 lines, with 59-line black bars wasted above
>> and below
>>
>> Both still use 720 pixels across the width of the image.
>>
>> So the primary benefit of an "enhanced for 16:9" DVD is increased
>> vertical resolution in the actual image area. It essentially lops
>> off the top and bottom -- which are wasted in letterboxed movies
>> anyway -- and stretches the rest vertically to more efficiently
>> display the available pixels. In theory, DVDs could be made in
>> actual 1.85:1 and 2.35:1 formats (or any other format desired), so
>> that they would waste NO pixels (that is, no black bars would ever
>> be recorded on the DVD and all available pixels on the DVD would be
>> used for actual image information), with the DVD player or TV doing
>> the appropriate stretching and scaling to the matching area on the
>> TV screen (and filling in the rest with black or gray pixels). But
>> they haven't gone that far yet.
>>
>> When it says "in original 1.85:1 aspect ratio" it means that it is
>> letterboxed, rather than pan-and-scanned (or horizontally
>> compressed, which I haven't heard of being done but might be a
>> plausible choice for transferring movies from 1.85:1 to 1.78:1).
>>
>> If the black bars you were seeing were substantially more than 10
>> pixels, then it's likely your DVD player or TV was set to expect a
>> 4:3 DVD. In that case, the image would also appear stretched out
>> horizontally (which you might or might not notice if you are already
>> accusted to watching regular TV stretched).

Thanks for taking the time for writing an "Aspect Ratio 101" primer; I shall
make a reference copy. Much appreciated!

I don't watch anything stretched, as I find it pretty annoying. In the case
of the film in question ("The Cooler" ), the box ID'd it as 1:85:1, but IMDB
says it is 2:35:1, so that pretty much answers that. However, I watched
another last night ("The Human Stain" ), and, again, the box said 1:85:1
(confirmed at IMBD), but there were black bars on top/bottom. Both my DVD
player and TV have the display set to 16:9. Would the black bars be
considered part of the 16:9 image as far as the DVD labelling is
concerned -- when it states "Widescreen (enhanced for 16:9 televisions)"?