An interesting find - have you got true widescreen playback?

[robburne]

Hi,

I have been having some trouble getting a widescreen AVI to convert to widescreen DVD-R. The problem was that in WinDVD and other software players my movie played perfectly widescreen but on a standalone the picture was cropped at the edges.

Intitally I guessed it must have been my error in authoring the movie somewhere along the line, but checking my files with IOFEdit revealed all was correct and my movie was correctly set up for a widescreen disc.

So I thought I would check things with a commercial disc, and sure enough I am also losing some of the picture on these discs too! Take a look at the attached jpg - it is a capture from a movie played in WinDVD, the purple bars represent what I am losing on my standalone.

Image:

I have a Toshiba 28" widescreen and I have tried adjusting the horizontal position and size but cannot gain the extra width that is lost. Are the TV companies selling us short here? Anyone else care to check their setup too?

Cheers,

Rob.

[Baldrick]

https://www.videohelp.com/glossary#Overscan

[robburne]

So I guess this is a safety feature so our picture on Tv remains undistorted but how annoying though as we are losing out aren't we.......

Do more expensive high-end TV's mange to avoid this problem or is it something we can do nothing about with a home cinema setup?

Rob.

[energy80s]

All TV's overscan the image, but by differing amounts. To see the full image, you need a PC screen.

[Bob W]

Hmm mad mad world, now that is a funny movie.

[energy80s]

Unlike Rat Race!

[vhelp]

Hi guys.

@ robburne,

I know exactly what you are saying. But, this is somehting I new for a while
now. That it does cut too much off. Actually, what Baldrick
posted won't help your (or I and others) w/ this problem. Your source
encode is correct - - HOWEVER, the aspect ratio (AR) is not !!

Yes, I know. "but I did it correctly" Yes, but there are several isues to
consider. I was gonna post this in the Star Wars thread going on now, but
I thought it was too lengthy and partially not w/in the thread's topic. So, I
opt for forgoe it in hopes that someone would give me a reason and "go
ahead, make me" - -


.
.
Noting the above pic as a reference...
(unfortunately, the pic got distorted when I used PowerDVD to snap it from
it's true 16:9 AR view)
The short version. Because the Cinema is using resolution of 853. You (and
I and others here) are using 720. So, on one side of the coin, the AR is
correct, and on the othe side, it's not. Remember, the normal AR we use
are based off a calc of DVD processed AR which are again, from 853.
When the DVD player does it's stuff, guess what is hapening. its factoring
in it's hardware profile's 853 spec (not 720) and resizing accordingly. And
guess what you getting in your TRUE commerical DVD disks ?? you got it.
You are getting the FULL area coverage. But, when you encode a DVD,
you are using doing so w/ an calc resolution of 720, and your DVD player
does not have specs telling it how to resize the video to show the whole
area (w/in the AR of things) - - that's the short version. Below is the much
more vanal version, based off my observation :P

Notes, if you read ares that makes mention about Star Wars, don't get upset,
I'm too lazy to snip and reword/phrase. So, here goes..

-- -- --

Ok, a little explaining about the 16:9 aspect ratio (AR) ...

My problem w/ the AR was due to the confusion of DVD vs. VHS and their
respective AR's. ..something the DJRumpy and Fulci never explained, or
did they realize :P Anyways..
.
.
There is a difference between a widescreen (WS) AR from a DVD vs. one from
a VHS. Both have different AR's due to the actual "resolution" they have
internally. Yes. The DVD is calculationally speaking w/ respect to the
origin of 853, while the made-for-tv is a mior 720 (if that - - think about
scanlines) I couldn't figure out why my WS 16:9 AR just didn't look quite
right. Again, DVD vs. VHS. When I played my encoded 16:9's (2:35.1) they
still didn't quite look the part. But, not I understand. And, dispite
the "slight" difference, these encodes (IMO) are proper 16:9, but
in a limited fasion. Hope I made sense.
.
.
Ok, to give you an idea. Here are some calculations to ponder.. given below
to maintain a consistant 2:35.1 AR:

Src -- width - - calc AR HT - - Calc AR - - - Crop x2 - Crop --
---------------------------------------------------------------------
DVD -- 853 - - - 362.525 - - - 2.352941176 - 117.475 - 58.7375
VHS -- 720 - - - 306.000 - - - 2.352941176 - 174.000 - 87.0000
VHS -- 640 - - - 272.000 - - - 2.352941176 - 208.000 - 104.000
VHS -- 640 - - - 360.000 - - - 1.777777778 - 120.000 - 60.000
VHS -- 352 - - - 149.600 - - - 2.352941176 - 330.400 - 165.200

DVD - asuming one is encoding based of it's (internal specs)
VHS - assuming from an Analog Capture of 720 Width, and 352 Width.

Note 1, below is the actual calc formula. Mind the const
number for the AR:

* Width / (16 / 6.8) ... = 2.35 .. (or 2.352941176)
* Width / (16 / 8.63) .. = 1.85 .. (or 1.853997683)
* Width / (16 / 9) ..... = 1.778 . (or 1.777777778)

Note 2, although the VHS-720-width has a 306 value, I did not follow through
w/ the calculated 306 crops (aka 87 pixels top/bott) It was wise to match
the source's .AVI's cropped "video area" using a different approach, so that
when "both" sources (.avi and mpeg-2) were aligned together, they would match
pixel to pixel.., hence a consistant AR look. It is my opinion that the closer
you maintain your AR, the better your final encode quality will be. But, the
unfortunate part of this, is that you have to fudge around w/ your source until
you meet as close (or exact) source's AR. That is a must in this field
of endeavors. This is another reason why I say that one should capture at the
maximum/fullest resolution posible.. but if in doubt, follow the above calcs
numbers to achieve your goal. You can apply the above VHS to your tipicle
Cable/Satellite captures as well, because they too, are 720 origin. Forget
about the confusing rumor of Satellite and 540/480 resolution. Thats not what
is important, but again, rather the AR - - assuming we're talking about WS
sources. FS is cokka and those are not for this disucussion. Handle
those as you see fit.

Note 3, As for DVDs.. This is a gray area. Only because I do not have the
total experience on it's respective specs and process. Too many hands are
in this process. Anyways..
Ok, short.. it's assumed that in respect to the calc above, that the source
that the Cinema people use are set to 853 as the resolution. So, that they
do their AR stuff, they squeez this 853 into a 720 width. When you
view it through your DVD player, Aspect Rationally speaking, it puts it out
into the proper view, hence the so called great quality. Now, lets take it
a step futher (or should I say, backwards) and start w/ a Cinema produced
source, VHS. Lets also assume that they scope it out w/ a 720 resolution.
Now, you have to Aspect Raitonally work w/ a 720 width vs. an 853 (of which
the 853 is "internal" to the source) and the 720 is not "internal". Hope
that made sense. The totally confusing part of trying to understand this is
that when you deal w/ VHS, you have to think in terms of "scanlines" because
that is what everybody is talking (arguing) about these days. "its not res
olution, it's 'scanlines') So, it's rather hard to decisfer.. are they
processing the VHS source w/ a 720 resolution, or is it "scanline" and the
fact there is no resolution, then Width/AR is not a factor. Sort of makes
your go cookoo
.
.
What we really need to know, once and for sure, is WHAT resolution
is the aim/intent, when they process widescreen VHS sources and AR factors

.
.
On to other notes w/ AR ...

It is my opinion that AR's vary from one source to another. It all depends
largely on how they produce it on the sources medium. DVD vs. VHS etc.
But, the point I want to make is this. When you talk about AR, don't always
assume that its (you calc the source's black bars w/ respect to the
source's "video area") and calc them as such. They will throw you off, because
this may not entirely be true, as they (in my experience) have viered from
this practice, and as such, they are not actually the true AR calc in all
transfer processes.. it depends upon "how much" they want to "scope" your
theoratricle experience vs. how much they want factor into the process. They are
just a part of the source being transfered. But, those responsible could have
added or reduced those black bars, depending upon how much of the "video area"
per "AR" area they want to scope for a given source medium (ie, DVD vs VHS)
.
.
I'm gonna assume that the Triligy set will not all have the same exact AR
numbers. Do they have the same exact "black bar" pixel area coverage, or do
they not. That is to be learned sooner enough

-vhelp 2205