Video 3D

trouvé sur Web3d :

Quote :

gael Ecrit le: lundi 27 février 2006, 00:58


Voici le blog de quelqun qui essaye de mettre au point une technique pour reconstituer une scene en 3D à partir d'une vidéo
Il utilise un caméscope normal avec un obejctif de sa fabrication et un algorythme pour recrée la scene en 3D

c'est assez impréssionant
http://blogs.nofrag.com/divide/

Hello,
interesting link. Currently there is much research on producing 3d spaces from 2d images and videos. Howeber truth is that, mathematically speaking there is no way to produse the real 3d space of which we have a video or a pictures (of course this is not my own opinion but what experts in the field say, see Takeo Kanade). What is being done in such projects, is the development of an algorithm, that enables the creation of a possible 3d space from a 2d picture/video by means of some certain rules i.e. "the more darker (of an area), the less extruded". Besides such algorithms are widely used in many 3d software - extrusion modifier in 3DSTUDIOMAX.


In my opinion the most interesting part in all this story would be to easily have such appplications in real time graphics. This aspect would allow for example the 3d digital representation of the user in the virtual world, as an alternative to his/her virtual repreentation - an avatar.

Such applications are currently possible to develop, but dedicated and expensive systems are presupposed. For this you may see "real-time 3d scanning", "tele-immersion", "augmented virtuality".

Does anyone know a real-time graphics software that would enable such applications, with the use of a standard webcam?

thanks and apologies for the lenghty post...

Hello,
is someone is interested in developing a home system for 3d scanning, you may google for "DAVID 3D SCANNER".
You only need to have,
a laser (50e let's say)
a webcam (20e let's say)
the "DAVID" software (it's free)
a PC.

Anthony

That sounds pretty interesting, Anthony.

I will google for David, but you could, meanwhile, tell us something more about it.

"David" ... hmmm ... wasn't there a "David" in Snowcrash ?

Huggs

The site is here:

http://www.cs.tu-bs.de/rob/david.html

Seems fairly straight forward, if a little fiddly to setup. I've got just about everything I need to do it, once I find the laser pointer.

Hello,
I have not made this system, so I can not provide further information about it. Neverheless, if I won't find a more interesting one, I will setup this.
I thought of posting this, so that we start a discussion concerning 3d scanning, in other words the automatic design of 3d models, which we will be able aftewards to incorporate in our 3d virtual worlds.

I would like to drive your attention especially to real time 3d scanning, because "DAVID" cannot do this. I have already explained in my previous post the reasons why real time 3d scanning is of immense interest.

Being able to digitise our physical hand, is the counterpart of having a virtual hand via a dataglove, please look my site:
http://users.ntua.gr/ar01664/mixed_reality/VR_glove/index.htm

I hope we could work a little together to this direction in this forum.

Anthony

yeaaaaaaaaaaaaaaaaaa !!!!!!!!!

))

http://users.ntua.gr/ar01664/mixed_reality/VR_glove/physics_simulation_vr_hand.gif

nice one !!!!!


btw I spent time to find a laser that mornig , but it iwas sunday , LOL
not easy ...

I will like very much if you could with all that here , thanx Anthony and all



......just a stupid joke with Bryce

( and a pic from jacinto webcam )

http://dumenieu.free.fr/louiseforum/jacintocambryce2.wrl


because

Quote :

the creation of a possible 3d space from a 2d picture/video by means of some certain rules i.e. "the more darker (of an area), the less extruded". Besides such algorithms are widely used in many 3d software

It brings to my mind an other sort of "virtualisation", the motion capture or(MOCAP). I guess this does allready exist for realtime, as it needs to process less data than DAVID.

In MOCAP, the mesh, the joints and the IK behaviour have alreay been calculated before runtime, and the scan "only" needs to tell the program where a couple of reference points are moving.

DAVID has got the advantage of using unexpensive hardware for scanning, but that probably results in a huge amount of data to be processed, and after that, the resulting mesh will need to be optimized in realtime, at least if you want to use it on the web.

In order to reduce the data flow, it will first need a fast but accurate beam-drive, that allows to scan only the needed amount of paralell lines, so that we feed the software just with a "few" needed vertices.

I have seen some laser light effects doing this simply with one mirror or a prisma driven by 3 speakers (lol, yes, such you have got in your radio). I don't know it this could work for our purpose. An other way would be to use 2 prismas driven each by a step-motor.

Just try to figure out, how easy it would be, if we just would need to feed the heights of an vrml elevation grid, that's not much data to be moved

The bad part of this approach is, that we would have a constant grid-spacing along the mesh, so either we loose details or we need tu use a very dense grid ...

Well, that's enough for sunday

What do you think ? Did I talk nonsense ?

Have a nice weekend all together.

Peter

Hello and thank you for your interest.

Alain gave us a link to a vrml application, that indeed a picture, modified a three dimensional surface. To my mind this is very interesting. However, in this application the modification of the surface is not made in real-time, as far as I saw i uses a jpf picture for creating a static surface extrude. Have you heard of such an application in real time?

Peter has right, such an application will be too slow to be done in real-time. However I ould be optimistic, as if we choose a low detail scanning, let's say 0,5 cm, we may be able to have 2-3 scanns in 1 second. "David" allows us to choose the detail we want. Have you heard of another 3d scanning application that performs these in real time?
In addition, Peter you say:
"In order to reduce the data flow, it will first need a fast but accurate beam-drive, that allows to scan only the needed amount of paralell lines, so that we feed the software just with a "few" needed vertices.

I have seen some laser light effects doing this simply with one mirror or a prisma driven by 3 speakers (lol, yes, such you have got in your radio). I don't know it this could work for our purpose. An other way would be to use 2 prismas driven each by a step-motor."
Could you please explain these to us a little more, and may be provide some links of related research?

I am about to setup the David system, if no other better application appears. But we may google a little more...

thanks

ah ....but I was just "joking" with the picture taken by a webcam ..

I know that for serious posting Peter or fabricator will be here

btw , I found the news on web3d-fr , when I copied this thread here ,
months ago ,
and there was an "answer" from my friend Steph :

http://www.web3d-fr.com/bp_breve.php3?id_breve=1653

Quote :

28 février 2006 : > Un scène en 3D à partir d’une caméra , par Steph
Cloud Of Points Of a Scanner

Il y a également un excellent site sur la création d’un scanner 3D avec peu de moyen : http://copos.berlios.de/documentations/bricolage/x29.htm

A vos lègos !....

no time to re check now , but may be interesting

Alain :

You'r teacher's jokes are allways didactic.
Your art-teacher's jokes, are allways artistic.
Your techie-art-teacher's jokes are allways interesting (at least).

Alain, you should know by now, that you're a respected person here arround (that's not a joke ).

I only do "bricolage", so don't you load my chest with such heavy weight.

Anthony :

When I say "beam-drive" i am probably using a non regular definition (i'm not "anglophone" ).

What I mean is, that we need something that authomaticaly beams our laser pointer following a given path or just aiming specific points upon the scan-area.

The scanning process would be faster (less passes)
Repeated values or measurement points would be avoided
The resolution of the scan could be set before scanning, depending on the object to be scanned
We could feed the resulting z-values directly into a mesh with given x, y pairs.
We would not need any major poligon reduction nor mesh optimization after the scan

Well, this would lead, at a beginning, to a very simple mesh, just overlaying the scanned object like a blanket... but there are plenty of ways to go further with it (i guess).

For the drives that I did mention ... ... well, I've got no links yet.

Let's say in advance, that the "3 speaker option" uses the movement of the speakers coil, triggered by cc voltage (not really, but it's not ac), for positioning the beam, the mirror or the prisma. I guess that we would need 3 coils for reproducing a more or less accurate x - y panning.

The step-drives (also an invented term, may be) are electric motors which may be positioned exactly. That means, they do not just turn like mad, they can be told to go to a desired rotation angle --> they turn step by step. Printers, plotters, scanners use that stuff.

The first option (speakers) would need a D/A converter, so that we could trigger the coils at different voltages, using our PC.

D/A converters are available for the most usual PC ports and are commonly shipped including the needed drivers.

The second option does also need a specific controller card, beside the servo-drives. They are also available for PC.

RS is a good adress for such stuff : http://www.rs-components.com/index.html

I will take a look as soon as possible.

Thank's for that interesting thread!

Peter

I things you still have a lots to learn about motion capture or so ;-)

jacinto wrote:

j ai pas trouver le topic sur 3d scanner...je voulais placer se liens

http://schizzo.free.fr/forum/viewtopic.php?id=34

all that is at your home jacinto ??,

http://schizzo.free.fr/images/autoportrait_2_2.wrl

wowwwwwwwwwwwwww ahahahaahhaaaa

coooooooooooooooooool ))))

how you make that ???????



ps and why not
?

Code:

 creaseAngle   9

mais super bien )) jacinto !

http://schizzo.free.fr/images/tigre_3.wrl

creaseangle

ahahah ah no c'est pas de ma faute ça ! ahahaha
not my fault )))

comment tu fais ça ??, alors , raconte ..

how you make that ?,

pardon...alain, la partie scan es tres simple,
tu fais tourne l objet sur le scanner a l envers de l avance de la lumiere du scanner,
voir xyz (pardon , mais c est expliquer..;heu)
pour la partie modelage , le resultat du scanner , que l on peu pas apeler "photo" mais plutot "map de luminosite" ou un truc comme ca.
je ferai un tuto , mais la theorie es la suivante:
mapper l image sur un cylindre et faire de l elevation des differentes nuance de gris.
comme pour faire un terrain avec les differentes nuances de gris d une image, sauf que la le terrain es courbe, c est un cylindre.

ps : pour faire une tete , tu tourne ta tete, sur le scanner ( dans le sens oposer de la translation du faisseau, pendant qu'il scanne, pas besoin de systeme mecanique, juste un scanner a plat

Un genio !!!!

Abrazos,

Peter

http://schizzo.free.fr/images/autoportrait_3.wrl

I want one !!!!!!!!!

what are your prices ???

not a joke !!!

can I pay by credit ??

not a joke !

will be my first art piece I will pay !

and a numeric one ! wowwwwwwwwwww !!

with my portrait of course plzzzzzzz

je comprend mal l'anglais, mais en gros tu veux ta tete ?
je te la fais gratos
ou si tu veux apprendre je te montre comment avec blender
remarque ca ira plus vite si je te la fais, en plus ca me feras plaisir hihi
A tu un scanner a plat ?
pendant que j y suis je peu aussi faire les tetes de peter, hermetic..

bah tu sais , je réagis souvent à chaud , sans trop réfléchir ,

donc ça m'a pris comme ça ..
mais je regrette pas .....

tu sais j 'ai vendu quelques tableaux , quand j'exposais dans une petite gallerie qui en vendait ..

mais art et argent , j'ai jamais été trop fort là dedans ,
j'ai arrëté , enfin ça s'est arrêté on pourrait dire Lol

quant à acheter des oeuvres ,

et d'une c'est super cher , et de 2 ça m'a jamais branché ..

trop long à dire pourquoi , je sais même pas si je le sais vraiment LOL


par contre quand j'ai vu ton truc ,

j'ai percuté ....


ya tout ce qui me plaît en ce moment

l'amitié ,
le virtuel ,

la 3d

etc

franchement l'idée que ce soit une "oeuvre" me plaît beaucoup ...

le coté " passer la commande " , par amitié , et autre , aussi ,
je suis en plein dans les portraits du 18ème , tu sais ,
à cause de l'agreg ,

faut voir le boulot ! commandes etc ,
passionnant ....

donc , faut valoriser l'art numérique , c'est un vrai boulot ,
t'es pas le premier ,
mais pour ça , le portrait 3D , t'es pas le dernier ..

je crois que jack en a un , je sais plus où ,
mais pas fait du tout pareil ,
et puis tes bidouillages , j'adore

réfléchis tranquille ....

pis fais moi un prix d'ami hein quand même , aahhahaah



je crois que je me brancherai bien sur mes photos où j'ai fais l'andouille à poil sur le net , LOL

ça me brancherai bien ça ))))

je te repond pareil achaud...
pour se qui est du portrait, ta l oeil, je dirai,
le prix de 93 des beaux arts c etait un ortrait avec une table trancante....
le plan, d 'aujourd hui je l avais en tete depuis plusieur annee je doit avouer..j ai trouver que cetait le moment...bon peu etre que je me trompe j aurai peu laisser cela encore quelque annee...
pour le portrait de jack c est un effet d optique dans son monde virtuel, je croi pas qu'il es avoir... mais encore dans se cas la sunjectiviter de l art jouant...bla bla..
bon ca serai marrant que tu passe ton scanne suivant les consigne de realisation? et arrete de me parlez d argent , tu sais a quel point je suis mal sur se sujet, et comme il es impensable que nous fassion se ganre de transaction financiere, alors ne parlons plus de cela.
pour parler d autre chose, j ai le concourt le 30, a paris ?
oui oui, mais je suis pas dans le coup, il vont se payer ma tete a mort, c est la le probleme pour moi, au lieu de faire le con avec l art le vrai selui que je considere comme le vrai, j aurai mieu fais de travailler le concours .... voila resultat .. bien fais pour ma queule, mais je prefere les webcam dans les spectacle de magie et les portrait avec les nouvelle technologie...Vraiment la vie es mal faites....

au fait moi j adore holbeins (ca s ecrit ainsi) c est le plus du plus du top du top, je le connais depuis ma tendre enfance ou j avais un livre de lui un grand livre d image par ,notre chere ecole en fin d'annee...