Hands-On Robotics Programming with C++

Capturing the image

To capture the image of your ball, place it on some dark surface. I have placed my green ball on a mobile phone case, which is black:

If your ball is black, or of a dark color, you can place the ball on a surface that has a light color. This is to make sure there is a very high contrast between the color of the ball and the color of the background, which will help us in thresholding later on.

While capturing the image, make sure that there are no white colored patches on the ball, as this may cause problems later on while thresholding:

The photo on the left has a big white region because of too much lighting. On the right, ...