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Recognize play card

By maxipigna on Fri, 10/04/2013 - 15:15

Hello, I want to implement an application for Android able to recognize play cards. In particular, my problem is that cards are arranged as here. So, I guess that the best way to recognize them is trying to read the number/letter (and symbol for the joker) on the corner, since I do not care about the suit of the cards. How can I do that? Sorry, but I am not an expert so please I need of your help.

AlessandroB

Fri, 10/04/2013 - 15:41

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At present, Vuforia does not allow recognizing a single letter (such as J, Q, K of the cards) or a single number.

Ok. But, what about to recognize letters and numbers as images? Because what I want to get is counting how many cards there are for each number/letter.

For instance, looking the previous example the first player has six Ks, one 7, five 8s, one 9, three Js and one joker. 

You could try, but the risk is that the letters / numbers, when handled as images, would result in a very low amount of details; i.e. the resulting image targets would likely have a low tracking rating;

see here for more details:

I think you are right, but I want to follow your suggestion and make an attempt.

I was tryng to upload an image by the Target Manager and it asks to insert the image width, how can I choose the right value of that parameter?

The width is an arbitrary value. It's used to define the unit scale of the coordinate system used for tracking. So you can use the real width of the card, or define your own unit. But it's best to use values above 2 to avoid falling below the near clipping plane of the camera fustrum.

Ok, I will set as parameter the width of the card.

I uploaded some images which got 2 or 3 stars. Maybe, if I edit the images I can get some star more. 

Now, I do not have an Android phone with me, so I can not test it. Is there another way to do that?

You can get a free 30 day trial of Unity Pro, which supports our simulator - https://developer.vuforia.com/resources/tutorials/vuforia-play-mode-unity

Thanks, I will test it by using your simulator.

Sorry, I meant that I could improve the rating by editing the image, I saw some tricks in your resources like increasing image contrast.