Pattern recognition using color...

robbyrne22

Pattern recognition using color...

in Integration and Hardware • 2 years ago

Hi,

I'm brand new to processing so please bear with me. I want to create (what I imagine is) a relatively simple program. A webcam will look down on a table. There are 3 colored shapes, red, green and blue. A pattern will be presented on screen with these colors and a child will have to match the pattern on the board using the shapes and click the mouse to indicate they are finished. I need the program to compare what the child has done to what was on screen and give a response, positive or negative. Any help would be greatly appreciated!

Rob

Replies(1)

jobleonard

Re: Pattern recognition using color...

2 years ago

Well, in this case you can use:

http://processing.org/reference/get_.html

.. to get the colour of an individual pixel. I assume the camera will be at a fixed setup, so figure out the x and y coordinates of where you want the objects to be put.

Then I would split the colours into their individual channels (red, green blue)

http://processing.org/reference/blue_.html

http://processing.org/reference/green_.html

http://processing.org/reference/red_.html

Since the colours will vary a bit I wouldn't test for a specific colour but for a range of colours. So no if (red == 128), that would leave you without a margin of error, and real life situations need that. Test each channel according to the appropriate colour they make up (so if (red > 200 && green < 20 && blue < 20) { do something } would be bright red).

You need to calibrate your program for a specific lighting situation, so make sure the lighting of the board is constant, and the white-balance doesn't automatically change in the webcam!