Robot Navigation Control Based on Monocular Images: An Image Processing Algorithm for Obstacle Avoidance Decisions

Listing 1

Threshold. The code calculating the thresholds for the Image Segmentatation step.

(1) for (int i = start Y; i < height; ++i)

(2) {

(3)     for (int j = start X; j < width; ++j)

(4)    {

(5)        unsigned char blue = pixel Data [i * step + j * channels];

(6)        unsigned char green = pixel Data [i * step + j * channels + 1];

(7)        unsigned char red = pixel Data [i * step + j * channels + 2];

(8)

(9)         if (red == 0 && green == 0 && blue == 0)

(10)           {

(11)                  continue;

(12)          }

(13)

(14)      //Find thersholds

(15)      if (red < mMinimumRed)

(16)      {

(17)        mMinimumRed = Red;

(18)      }

(19)

(20)      if (red > mMaximumRed)

(21)      {

(22)                  mMaximumRed = Red;

(23)      }

(24)

(25)      int redGreenRange = red – green;

(26)      int redBlueRange = red – blue;

(27)

(28)      if (redGreenRange < mRedGreenRangeMin)

(29)      {

(30)           mRedGreenRangeMin = redGreenRange;

(31)      }

(32)

(33)      if (redGreenRange > mRedGreenRangeMax)

(34)     {

(35)        mRedGreenRangeMax = redGreenRange;

(36)      }

(37)

(38)      if (redBlueRange < mRedBlueRangeMin)

(39)     {

(40)        mRedBlueRangeMin = redBlueRange;

(41)      }

(42)

(43)      if (redBlueRange > mRedBlueRangeMax)

(44)      {

(45)           mRedBlueRangeMax = redBlueRange;

(46)      }

(47)   }

(48) }