A quick question.
Why is paper required when viewing a 3D AR image through your phone? Whenever I watch a youtube video of someone demonstrating AR they anyway place paper within the view of the camera. Is it used as a point of reference or something? Can any paper be used or does it need to be specific to the image being displayed? Does it need to be paper or would any square or rectangular surface such as the kitchen table be used?
Thanks
- Yes, it will be used as a point of reference. Objects could be placed on top of a paper and so would be parallel to the ground. Else you would need some calibration method to recognize the ground. The IMU could be used but it's not always accurate enough.
- With Vuforia SDK you could either predefine a printing or allow the user to take a picture of any planar surface. When you're predefining a printing you can be sure, that it is appropriate for tracking and you could use it as an advert for your app. On the other hand, allowing the user to use any paper with enough details, is more user-friendly as one won't need a printer.
- Target papers don't need to be retangular, it only must contain enough features. Most frameworks use corners as "features". So circular shapes are inappropriate. Also you have to make sure the surface has enough contrasts.
Note that there are methods to do it without a paper, but you have to solve the calibration issue and accept measuring errors. At this moment there isn't any free framework, which supports that out-of-the-box, but as a strating point you could read Luca's answer to one of my questions.