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How to do AR on a big screen, need some input

March 24, 2014 - 1:26am #1

I am new to AR development and cant really code, yeah im one of those :P

I am working on a project in school an would like to do something like this http://youtu.be/jEW0LdNuFXY

Im testing it at my livingroom where i have a target image on the floor and then want to add water on the floor, but i have some problems
1: The target is 2-3 meters from the webcam im using, but the webcam cant read the target on the floor, so i have to move it closer to the webcam by hand and then place it back on the floor when the AR is activated.

2: When the AR is running the water is on the screen, but it is not flat on the floor on top of the target image, when i think about it, it looks like the water is placed in air maybe where i hold the target image by hand.

What i want to do, i the webcam to recognize the target image on the floor X meters away from the webcam (the moviefeed is clear and sharp), but i dont know how or where to do it.
Then i want the water to lay flat on the floor on top of the target image.

I have made a picture of the setup right now:
[img]http://soulstones.dk/upload/help/AR_Help.jpg[/img]

So what im using right now is a Computer, Webcam, Vuforia, Unity, TV

I hope someone can help me, and please explain it for dummies :)

AttachmentSize
Image icon AR_Help.jpg7.76 KB

How to do AR on a big screen, need some input

March 24, 2014 - 6:43am #3

I will try and play around with the Far value and the size of my target, i know that could be a bit bigger.

About the Webcam, i know its not the best solution atm but its what i have for the prototype, on the real thing i think i would use a real camera of some sort, i dont think a mobile device has a good enough camera, the idea is to make it more or less the same as the coca cola video in the first post, just with other content. so everything will be static except for the people that will on the side.

But right now im testing it in my livingroom and when that is working i will scale it up.

About the problem i have with the angle, will that be fixed if i get the right Far value and the right size of the target ?
Im not sure if i have explained myself so other than be can understand it, think i will make another diagram when i get more time.

But thank you for your fast reply :)

How to do AR on a big screen, need some input

March 24, 2014 - 2:11am #2

Hi,

your question is very broad, and partially beyond the scope of Vuforia, but I'll try to answer what I believe  is relevant to this Forum:

The target is 2-3 meters from the webcam im using, but the webcam cant read the target on the floor, so i have to move it closer to the webcam by hand and then place it back on the floor when the AR is activated.

Consider the following:

- the Vuforia samples use a Far Clipping Plane of 2500, which means that any object beyond 2.5 meters will be clipped and tus not visible; go to the ARCamera inspector panel and check the Clipping Planes => increase the Far value to something bgger (e.g. 5000 for example)

- the size of the target should be somehow adapted for the 3 meters distance; for example, consider a target with a width / height of 30-40 cm or more

- the angle at which the camera looks at the target is also relevant; if this angle is too steep (i.e. if the target is oblique), this could affect the detection

- very important: the Webcam is not an ideal choice, as its focus behaviour is not ideal; in Vuforia you can use a webcam in Unity n Play Mode as a mean of testing, but you should then deploy you app on a real mobile device (Adroid or iOS), as in this case, the focus behaviour will be much better and you shuld get better results (and you could attach your mobile device to a large TV screen using an HDMI cable).

I hope this helps.

Good luck with your project.

 

 

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