http://mi.eng.cam.ac.uk/~qp202/my_papers/BMVC09/
-- 
Darren New, San Diego CA, USA (PST)
   You know the kamikaze monsters in Serious Sam
     with the bombs for hands, that go AAAAAHHHHHHHH!
   I want that for a ring tone.

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Doesn't appear to be very accurate though... (And that's only for 
objects with trivial geometry.)

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Invisible wrote:
> Doesn't appear to be very accurate though... (And that's only for 
> objects with trivial geometry.)

Well, it *is* a doctoral thesis. Wait till it gets productized. You're 
seeing a proof of concept here.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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>> Doesn't appear to be very accurate though... (And that's only for 
>> objects with trivial geometry.)
> 
> Well, it *is* a doctoral thesis. Wait till it gets productized. You're 
> seeing a proof of concept here.

LOL. Is "productized" even a word?

Anyway, you're acting like once you can turn a pair of images into a 
grainy, vaguely-correct 3D model, it will then be a "trivial" task to 
turn this into something that actually works properly. I'm not sure it is.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Orchid XP v8 wrote:
>>> Doesn't appear to be very accurate though... (And that's only for 
>>> objects with trivial geometry.)
>>
>> Well, it *is* a doctoral thesis. Wait till it gets productized. You're 
>> seeing a proof of concept here.
> 
> LOL. Is "productized" even a word?

It is in my country, yes.

> Anyway, you're acting like once you can turn a pair of images into a 
> grainy, vaguely-correct 3D model, it will then be a "trivial" task to 
> turn this into something that actually works properly. I'm not sure it is.

I imagine one could not too difficultly add code that would help the 
software figure out what it needs to see to be correct. It'll certainly be 
easier to start with the almost-right model than to start from scratch.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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> I imagine one could not too difficultly add code that would help the 
> software figure out what it needs to see to be correct. It'll certainly be 
> easier to start with the almost-right model than to start from scratch.

Even if it can't get it 100% correct, it would be great for very quickly 
getting a 95% correct mesh done (with textures!), that only requires a bit 
of tidying up in a modeller knowing that the overall dimensions and 
proportions are correct.

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>> I imagine one could not too difficultly add code that would help the 
>> software figure out what it needs to see to be correct. It'll 
>> certainly be easier to start with the almost-right model than to start 
>> from scratch.
> 
> Even if it can't get it 100% correct, it would be great for very quickly 
> getting a 95% correct mesh done (with textures!), that only requires a 
> bit of tidying up in a modeller knowing that the overall dimensions and 
> proportions are correct.

I guess I was hoping for a system that would take a pair of photos and 
reproduce the blades of the grass, or the bumpmap of the grain in the 
wood, or the individual sugar grains in a sugar jar, or similar. You 
know, like the human eye can. The demo here seems very far from this level.

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> I guess I was hoping for a system that would take a pair of photos and 
> reproduce the blades of the grass, or the bumpmap of the grain in the 
> wood, or the individual sugar grains in a sugar jar, or similar. You know, 
> like the human eye can.

That's impossible from two photos, you may *think* your eyes can do this 
perfectly, but a lot of it is just your brain making stuff up based on what 
it is expecting to be there.

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>> I guess I was hoping for a system that would take a pair of photos and 
>> reproduce the blades of the grass, or the bumpmap of the grain in the 
>> wood, or the individual sugar grains in a sugar jar, or similar. You 
>> know, like the human eye can.
> 
> That's impossible from two photos, you may *think* your eyes can do this 
> perfectly, but a lot of it is just your brain making stuff up based on 
> what it is expecting to be there.

Wouldn't it depend on the resolution of the images and the size of the 
objects in question?

You can't make out sand grains on the brach from 4 miles out to sea, but 
I'm damned well sure you can when you're laying in the sand reading a 
book. :-P

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> Wouldn't it depend on the resolution of the images and the size of the 
> objects in question?

No, it's a simple fact that with only two photos there is never enough 
information to make a 3D model and be sure it is correct.  Your brain always 
has to add in unseen or assumed details, which most of the time are 
believably correct, but I guess this is extremely hard for a computer to do 
(as it's based on your experiences etc).

Using your grass example, I'm sure lots of blades will be hidden by others 
in the view from one eye, but plainly visible in the view from the other 
eye - how can a computer know what to do with that?  Even if the computer 
could somehow match up individual blades of grass between the two images, 
the partially hidden ones it would just have to guess where they were within 
a certain range of positions.

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>> Wouldn't it depend on the resolution of the images and the size of the 
>> objects in question?
> 
> No, it's a simple fact that with only two photos there is never enough 
> information to make a 3D model

I don't think that's true.

> and be sure it is correct.

Oh, right. That's slightly different.

> Your brain 
> always has to add in unseen or assumed details, which most of the time 
> are believably correct, but I guess this is extremely hard for a 
> computer to do (as it's based on your experiences etc).

I think the primary thing that stereoscopic vision gives you is depth 
perception. Using it, you can tell, with reasonable accuracy, how far 
away a given surface is. (Seems to be more accurate for near objects; 
very distant ones like clouds tend to look "flat".)

I would have thought it ought to be possible to take a stereo photograph 
and construct a kind of texture-mapped height field from that. I agree 
that if you take a picture of a cup, the computer doesn't really stand a 
chance of figuring out what the *back* of the cup looks like.

Now, if you take lots of pictures from lots of different angles... well, 
I'm guessing the hard part is going to be figuring out how the images 
"fix together".

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On 11/30/2009 5:28 AM, Invisible wrote:
> I think the primary thing that stereoscopic vision gives you is depth
> perception. Using it, you can tell, with reasonable accuracy, how far
> away a given surface is. (Seems to be more accurate for near objects;
> very distant ones like clouds tend to look "flat".)

Stereoscopic vision allows you to triangulate an object's position, just 
like a surveyor can determine an object's position by forming a triangle 
between an object and two reference points.

--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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I thought this video was fitting:

http://www.youtube.com/watch?v=3609OtM138c

He talks about "one day" people being able to create 3D models from all 
the pics lying around the net of him. I guess that day has finally come 
true!!

:)


--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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SharkD wrote:

> He talks about "one day" people being able to create 3D models from all 
> the pics lying around the net of him. I guess that day has finally come 
> true!!
> 
> :)

For some reason, the first thought that popped into my head was "OMG - 
the goatse guy! NOOOOOO!!!"

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Invisible wrote:
>>> Wouldn't it depend on the resolution of the images and the size of
>>> the objects in question?
>>
>> No, it's a simple fact that with only two photos there is never enough
>> information to make a 3D model
> 
> I don't think that's true.
> 

http://www.youtube.com/watch?v=MikG05MV3GU&feature=related

Take any two frames, and tell me if the blue or white side is convex.

> I would have thought it ought to be possible to take a stereo photograph
> and construct a kind of texture-mapped height field from that. I agree
> that if you take a picture of a cup, the computer doesn't really stand a
> chance of figuring out what the *back* of the cup looks like.

Stereo photographs suffer from one problem that the eyes do not appear
to, focus. The brain and eye do all the 'number crunching' to preserve
the information and make you think everything is still in focus,
allowing your eyes to shift and pick up other details. Which also helps
with distance recognition.

To do that with a camera, you would need a ton of pictures or a very
small aperture. The first benefits in adding extra ranger information,
the latter only helps in the amount of data to be processed.

From a picture of a cup, shot edge on in full diffuse lighting, I doubt
a computer could even tell you if it was round, square, or any other
convex or concave shape. Not from just two pictures.

> Now, if you take lots of pictures from lots of different angles... well,
> I'm guessing the hard part is going to be figuring out how the images
> "fix together".

Which is what makes this software look kinda neat. Not only is it doing
that work, but it appears to be doing it in real time.

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Invisible wrote:
> I think the primary thing that stereoscopic vision gives you is depth 
> perception. 

That and the ability to see around close-by objects.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Invisible <voi### [at] devnull> wrote:
> I think the primary thing that stereoscopic vision gives you is depth 
> perception.

  The lack of depth perception of people who are blind on one eye has been
greatly exaggerated. People with only one seeing eye have a surprisingly
good depth perception.

  And that doesn't take years. It takes just a minute or so. You can test
it yourself, and it's actually quite awesome. For instance, watch a 3D game
of even a movie with one eye (cover your other eye with something). In a
few tens of seconds you will start seeing the game with depth perception.
It will start looking truly three-dimensional (not *exactly* as well as
a real three-dimensional scene looked with both eyes, but almost).

  The reason is that the brain is really good at compensating for the lack
of stereoscopic view, and will start to use secondary clues to form a
perception of depth.

-- 
                                                          - Warp

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>> I think the primary thing that stereoscopic vision gives you is depth 
>> perception.
> 
>   The lack of depth perception of people who are blind on one eye has been
> greatly exaggerated. People with only one seeing eye have a surprisingly
> good depth perception.

Shut one eye. The world doesn't really look any different.

Now try and pick something up.

Oh. OK, my hand is actually nowhere near. I guess depth perception *is* 
important after all.

(Even more fun is trying to drive with one eye shut. I strongly 
recommend that you *never*, ever try this!)

On the other hand, if you're looking at a *moving* picture, you still 
have parallax to aid you. Not to mention that many types of surfaces 
have patterns that are predictable enough to allow you to guess how far 
away they are.

(It is notable, actually, that certain natural objects possess such 
scale-invarience that you can't reliably tell how big they are. Rocks 
work well in this regard...)

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Invisible <voi### [at] devnull> wrote:
> >> I think the primary thing that stereoscopic vision gives you is depth 
> >> perception.
> > 
> >   The lack of depth perception of people who are blind on one eye has been
> > greatly exaggerated. People with only one seeing eye have a surprisingly
> > good depth perception.

> Shut one eye. The world doesn't really look any different.

> Now try and pick something up.

  Yes, because a few seconds will certainly be enough for your brain to
adjust.

  Did you try what I suggested?

-- 
                                                          - Warp

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>>>   The lack of depth perception of people who are blind on one eye has been
>>> greatly exaggerated. People with only one seeing eye have a surprisingly
>>> good depth perception.
> 
>> Shut one eye. The world doesn't really look any different.
> 
>> Now try and pick something up.
> 
>   Yes, because a few seconds will certainly be enough for your brain to
> adjust.
> 
>   Did you try what I suggested?

I haven't tried doing this over an extended time period, no. However, if 
it's anything like other human senses, I would imagine the brain manages 
to compensate to at least some degree after a while...

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On 11/30/2009 11:34 AM, Warp wrote:
>    And that doesn't take years. It takes just a minute or so. You can test
> it yourself, and it's actually quite awesome. For instance, watch a 3D game
> of even a movie with one eye (cover your other eye with something). In a
> few tens of seconds you will start seeing the game with depth perception.
> It will start looking truly three-dimensional (not*exactly*  as well as
> a real three-dimensional scene looked with both eyes, but almost).

Of course stereoscopic vision is not going to work when watching a 
movie!!! It's a 2D screen! LOL!

Mike


--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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On 11/30/2009 11:34 AM, Warp wrote:
>    The lack of depth perception of people who are blind on one eye has been
> greatly exaggerated. People with only one seeing eye have a surprisingly
> good depth perception.

Can anyone think of a single athlete with only one eye?


--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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Warp wrote:
> For instance, watch a 3D game of even a movie with one eye 

More to the point, the general public doesn't have access to 3D games or 
(usually) movies at all. It's *all* a flat TV screen.

Yet, oddly enough, one learns to aim the grenade launcher to land the 
grenade where you want it to go, even without stereoscopic visuals.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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SharkD wrote:
> Can anyone think of a single athlete with only one eye?

Sure. I even know basketball players with no legs.

They're not world class players, mind.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Invisible <voi### [at] devnull> wrote:
> >   Did you try what I suggested?

> I haven't tried doing this over an extended time period, no.

  Then why don't you? It's cool. Eg. 3D games look really cool that way.
If nothing else, watch someone else playing eg on youtube or whatever.

-- 
                                                          - Warp

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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > For instance, watch a 3D game of even a movie with one eye 

> More to the point, the general public doesn't have access to 3D games or 
> (usually) movies at all. It's *all* a flat TV screen.

  I don't understand. The general public doesn't have access to games or
movies? I don't get it.

-- 
                                                          - Warp

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Warp <war### [at] tagpovrayorg> wrote:
> Darren New <dne### [at] sanrrcom> wrote:
> > Warp wrote:
> > > For instance, watch a 3D game of even a movie with one eye 

> > More to the point, the general public doesn't have access to 3D games or 
> > (usually) movies at all. It's *all* a flat TV screen.

>   I don't understand. The general public doesn't have access to games or
> movies? I don't get it.

  Ok, maybe we are having a confusion of terminology.

  This is a 2D game:

http://upload.wikimedia.org/wikipedia/en/5/50/NES_Super_Mario_Bros.png

  This is a 3D game:

http://upload.wikimedia.org/wikipedia/en/d/de/Doom_ingame_1.png

  Clearer now?

-- 
                                                          - Warp

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>>> For instance, watch a 3D game of even a movie with one eye 
> 
>> More to the point, the general public doesn't have access to 3D games or 
>> (usually) movies at all. It's *all* a flat TV screen.
> 
>   I don't understand. The general public doesn't have access to games or
> movies? I don't get it.

I think he means the public don't have access to stereoscopic viewing 
technologies.

The military has (for example) those TV screens with the weird 
flickering LCD glasses that give you a headache but also generate a true 
full-colour stereo image...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Orchid XP v8 <voi### [at] devnull> wrote:
> >>> For instance, watch a 3D game of even a movie with one eye 
> > 
> >> More to the point, the general public doesn't have access to 3D games or 
> >> (usually) movies at all. It's *all* a flat TV screen.
> > 
> >   I don't understand. The general public doesn't have access to games or
> > movies? I don't get it.

> I think he means the public don't have access to stereoscopic viewing 
> technologies.

  Then it's unrelated to what I wrote, and an odd response.

  I was nowhere talking about any stereoscopic viewing technologies.

-- 
                                                          - Warp

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Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>> For instance, watch a 3D game of even a movie with one eye 
> 
>> More to the point, the general public doesn't have access to 3D games or 
>> (usually) movies at all. It's *all* a flat TV screen.
> 
>   I don't understand. The general public doesn't have access to games or
> movies? I don't get it.

Not in 3D. Just in perspective.

Contrast with a movie theatre where you wear special glasses, or with a play 
or puppet show.

My point being that even with both eyes open, looking at light projected on 
a 2D flat movie screen, you still have a sense of depth. You know Bruce 
Willis' car is closer than the bad guy's helicopter even if it's a flat 
photo on a flat screen.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
> http://upload.wikimedia.org/wikipedia/en/d/de/Doom_ingame_1.png
>   Clearer now?

That's a game drawn in perspective, is my point.

This is a 3D movie:
http://www.insidesocal.com/tomhoffarth/3D-glasses-404_675044c.jpg

:-)

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
>   Then it's unrelated to what I wrote, and an odd response.

I was agreeing with you.  Not only can you see "depth" with one eye closed, 
you can see "depth" that isn't there with both eyes open.  You don't have 
that hard a time judging how far away the enemy is and who is closer in a 
1st-person shooter, regardless of how many eyes you open.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > http://upload.wikimedia.org/wikipedia/en/d/de/Doom_ingame_1.png
> >   Clearer now?

> That's a game drawn in perspective, is my point.

  Sorry, I don't get your point.

  *My* point was that if you start watching a 3D game (perspective, whatever
you want to call it) like Doom or Half-Life with one eye only, you will
start getting quite cool depth perception. Not many people know this because
they have never tried.

  *Your* point I missed completely.

  Rather than nitpicking about terminology, just try it. It's cool.

-- 
                                                          - Warp

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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> >   Then it's unrelated to what I wrote, and an odd response.

> I was agreeing with you.  Not only can you see "depth" with one eye closed, 
> you can see "depth" that isn't there with both eyes open.  You don't have 
> that hard a time judging how far away the enemy is and who is closer in a 
> 1st-person shooter, regardless of how many eyes you open.

  Of course the brain needs the visual clues given by parallax and other
even subtler details (such as recognizable shapes) in order to maintain
the compensated depth perception. If you eg. pause the game/video for some
time, you will start losing the depth perception again, until you resume
it and start getting the visual clues again.

  With stereo vision you maintain the depth perception even with a
completely static three-dimensional scenery.

-- 
                                                          - Warp

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Darren New <dne### [at] sanrrcom> wrote:
> My point being that even with both eyes open, looking at light projected on 
> a 2D flat movie screen, you still have a sense of depth. You know Bruce 
> Willis' car is closer than the bad guy's helicopter even if it's a flat 
> photo on a flat screen.

  But my point is that with one eye the depth perception will be much
stronger (which is something many people don't know).

  (Of course one could ask, why then don't we always watch movies and
play games with one eye only? It's actually a bit tiring to do that for
a long time. And somehow the picture just isn't as clear as with both
eyes. You can try it.)

-- 
                                                          - Warp

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On Mon, 30 Nov 2009 11:34:26 -0500, Warp wrote:

>   The lack of depth perception of people who are blind on one eye has
>   been
> greatly exaggerated. People with only one seeing eye have a surprisingly
> good depth perception.

It depends on how long they've been affected by it.  My dad had very poor 
peripheral vision and near the end of his life was almost completely 
blind in one eye - he had absolutely no depth perception at all 
(demonstrated to me several times when I tossed car keys to him and he 
could never tell how far away they were).

Those who are affected by such a condition for most of their life, 
though, have often adjusted to their circumstances.

Jim

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On 11/30/2009 6:01 PM, Darren New wrote:
> Contrast with a movie theatre where you wear special glasses, or with a
> play or puppet show.
>
> My point being that even with both eyes open, looking at light projected
> on a 2D flat movie screen, you still have a sense of depth. You know
> Bruce Willis' car is closer than the bad guy's helicopter even if it's a
> flat photo on a flat screen.

In both video games and movies you don't have to worry about keeping 
objects in focus. In film it's taken care of by the camera operator; in 
video games things are never out of focus. I'll admit that if we had 
perfect focus at all distances like a pinhole camera, then maybe we 
would have an easier time judging depth with just one eye, as there 
would be essentially no delay as our eyes focus.


--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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Warp wrote:
>   *My* point was that if you start watching a 3D game (perspective, whatever
> you want to call it) like Doom or Half-Life with one eye only, you will
> start getting quite cool depth perception. Not many people know this because
> they have never tried.

OK, I'll give it a try.

>   *Your* point I missed completely.

That you have a degree of depth perception in a "3D game" like half-life 
even with both eyes open.

>   Rather than nitpicking about terminology, just try it. It's cool.

I wasn't really nit-picking about terminology. I was simply trying to 
explain what I was talking about. Namely, that you can easily judge depth in 
a game that only has one image, so you can easily judge depth with one eye 
open looking at the real world.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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Warp wrote:
>   But my point is that with one eye the depth perception will be much
> stronger (which is something many people don't know).

I didn't know that. I'll give it a try.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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"Warp" <war### [at] tagpovrayorg> wrote in message
news:4b1451f2@news.povray.org...
> Darren New <dne### [at] sanrrcom> wrote:
> > My point being that even with both eyes open, looking at light projected
on
> > a 2D flat movie screen, you still have a sense of depth. You know Bruce
> > Willis' car is closer than the bad guy's helicopter even if it's a flat
> > photo on a flat screen.
>
>   But my point is that with one eye the depth perception will be much
> stronger (which is something many people don't know).

It's not depth perception that's stronger with one eye (which would be
absurd). It's eactly the opposite: For best result watching a *flat* screen,
you do want to eliminate your own depth perception altogether. With two
eyes, you are noticing the actual 3D surface geometry of the screen itself
(especially if your eyes wander or your head is not still) plus a 2D surface
texture. With one eye only, your eye can more easily "replace" the camera
with which the movie was shot.

Post a reply to this message

somebody <x### [at] ycom> wrote:
> It's not depth perception that's stronger with one eye (which would be
> absurd).

  Watching a moving 3D scenery which has been projected onto a 2D plane
(such as a computer game or a movie) with one eye *does* give you a stronger
perception of depth than watching it with both eyes. If you don't believe
it, try it. (Give your brain about a minute to adapt.)

  It's not absurd. The brain is quite good at compensating for lack of
stereo vision.

-- 
                                                          - Warp

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SharkD <mik### [at] gmailcom> wrote:
> in video games things are never out of focus.

  You clearly haven't played any moder videogame. ;)

-- 
                                                          - Warp

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Jim Henderson <nos### [at] nospamcom> wrote:
> (demonstrated to me several times when I tossed car keys to him and he 
> could never tell how far away they were).

  The brain cannot adapt to such a small object making such a rapid movement
with one eye only. The visual clues are too subtle and too fast.

  Instead, put the keys on a table, and then walk from afar towards the
table with one eye covered, and take the keys. At least I don't have the
slightest problem in doing that. That's because the brain has time to
estimate the distance to the keys accurately while you are walking,
watching the keys.

-- 
                                                          - Warp

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Warp wrote:
> SharkD <mik### [at] gmailcom> wrote:
>> in video games things are never out of focus.
> 
>   You clearly haven't played any moder videogame. ;)

I am highly amused at the visual effects of Batman getting clubbed with a 
pipe, or how the screen goes all fuzzy while you're choking the crap out of 
someone. :-)

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

Post a reply to this message

On Tue, 01 Dec 2009 11:15:11 -0500, Warp wrote:

> Jim Henderson <nos### [at] nospamcom> wrote:
>> (demonstrated to me several times when I tossed car keys to him and he
>> could never tell how far away they were).
> 
>   The brain cannot adapt to such a small object making such a rapid
>   movement
> with one eye only. The visual clues are too subtle and too fast.

Yes, that was my point.

>   Instead, put the keys on a table, and then walk from afar towards the
> table with one eye covered, and take the keys. At least I don't have the
> slightest problem in doing that. That's because the brain has time to
> estimate the distance to the keys accurately while you are walking,
> watching the keys.

The wonderful thing about the brain is that there are may different ways 
for them to work.  Some people have an easier time with some things than 
others as a result.

Jim

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Jim Henderson <nos### [at] nospamcom> wrote:
> On Tue, 01 Dec 2009 11:15:11 -0500, Warp wrote:

> > Jim Henderson <nos### [at] nospamcom> wrote:
> >> (demonstrated to me several times when I tossed car keys to him and he
> >> could never tell how far away they were).
> > 
> >   The brain cannot adapt to such a small object making such a rapid
> >   movement
> > with one eye only. The visual clues are too subtle and too fast.

> Yes, that was my point.

  You seemed to disagree with the claim I made, which you were responding to,
that the lack of depth perception of people blind on one eye has been
greatly exaggerated.

  Depth perception may have been diminished, and the depth of rapid
spontaneous movement may be hard to visualize, but that's far from how
one-eyed vision is depicted in popular culture, which is absolutely
exaggerated. What a one-eyed man sees is more than what a camera sees
because the brain really *adds* depth perception from secondary clues.

  As I have been writing, you can test that for yourself eg. by watching
a computer game or movie, and the effect is quite cool.

-- 
                                                          - Warp

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On Tue, 01 Dec 2009 13:15:06 -0500, Warp wrote:

>   You seemed to disagree with the claim I made, which you were
>   responding to,
> that the lack of depth perception of people blind on one eye has been
> greatly exaggerated.

I do think that claim is inaccurate, yes.

>   Depth perception may have been diminished, and the depth of rapid
> spontaneous movement may be hard to visualize, but that's far from how
> one-eyed vision is depicted in popular culture, which is absolutely
> exaggerated. What a one-eyed man sees is more than what a camera sees
> because the brain really *adds* depth perception from secondary clues.
> 
>   As I have been writing, you can test that for yourself eg. by watching
> a computer game or movie, and the effect is quite cool.

I have done so several times myself, but it seems to me that it makes a 
difference whether or not your brain has been trained to make the 
adjustment.  Those who are sighted in both eyes have brains that can 
compensate for diminished capacities in some ways, however those who have 
never had sight in one eye experience the world differently than you or I 
do, so to say that their brains can compensate for this in the same way 
ours can when we just close one eye is, IMHO, inaccurate.

Jim

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"Warp" <war### [at] tagpovrayorg> wrote in message
news:4b15402a@news.povray.org...
> somebody <x### [at] ycom> wrote:
> > It's not depth perception that's stronger with one eye (which would be
> > absurd).
>
>   Watching a moving 3D scenery which has been projected onto a 2D plane
> (such as a computer game or a movie) with one eye *does* give you a
stronger
> perception of depth than watching it with both eyes. If you don't believe
> it, try it. (Give your brain about a minute to adapt.)
>
>   It's not absurd. The brain is quite good at compensating for lack of
> stereo vision.

I know what you are seeing and don't disagree, but you are using odd
terminology. There's no _depth_ on a flat 2D panel to perceive. What you are
seeing is an illusion, which is made more convincing by _eliminating_ the
real depth perception so that your mind is more suggestible to the presented
one.

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On 12/1/2009 11:33 AM, Darren New wrote:
> I am highly amused at the visual effects of Batman getting clubbed with
> a pipe, or how the screen goes all fuzzy while you're choking the crap
> out of someone. :-)

Er... Can you show me an example of a video game that doesn't use a 
pinhole-type camera?

--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com

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SharkD wrote:
> Er... Can you show me an example of a video game that doesn't use a 
> pinhole-type camera?

Anything with lens flair. The new Batman game I referred to.  I'm not sure I 
can *show* you an example, but I can name you examples.

-- 
Darren New, San Diego CA, USA (PST)
   Human nature dictates that toothpaste tubes spend
   much longer being almost empty than almost full.

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