How to detect red color ball with a if statement in MATLAB

[umagon]

as the title above, i wanted to write a code if red color ball was detected, the led will lit on (in MATLAB). how to write a IF statement to make sure the red ball was detected from the webcam? and how to determine the range of RGB value

let say i have a variable A = a ball bound in a box, then by using a IF, if the ball that bounded in the box (variable A) is red, then led will on

please help, thanks alot

 

[devilwar]

Since you are using a webcam, not all adapter would give the same RGB result for a single color. They might be just the same but they may vary by a point or so which makes detection of color very difficult. Hereby you have to go for a check of the red color ball for its corresponding RGB value. You may say this as a training phase.

aqVideo = videoinput('winvideo', 1, 'RGB24_640x480');
preview(aqVideo);

In the preview screen, place the ball close to the camera with decent focus such that the major part of the picture is covered by the ball.

aqImage = getsnapshot(aqVideo); // This will acquire the image/snapshot.

Once done calculate the RGB values of the pixel which appears the most.

Regards,

Devilwar