Playing Card Image Recognition - Java

Need a software that would recognise the largest or the clearest visible playing card in a picture of Playing cards. For example, in the image uploaded here, the card A of Hearts is the most prominent card visible here. - The program should be a web program. It should use Java Advanced frameworks - anything is fine - servlets, jsps, jsf, struts, spring mvc, rest web services. Choose whichever you need to. - The server can be any open source server - preferably Tomcat. - I want a page with a button that should be clickable. - The idea is that I will keep this web page open in a small sized window and click the button. - This button should take a screen shot of the whichever web page I have kept opened on the rest of the page. - As soon as the screenshot is taken it should recognise the largest card open on the page. - As soon as the button is clicked it should send in the data. For e.g. cardValue = A and cardType = Hearts. Use any data structure to store this data. JSON format is also fine. The program should do the above things. Keep in mind that this program will interact with another Java application. So in short the program should read the screen that I have kept open and send me the information of the largest card open on a user event like click a button. I am open to suggestions to any other better way to get this implemented. There is more upcoming work to the freelancer if this work is done well