Revision history [back]

This is my code for detect shadow:

void ShadowDetection(Mat image)

{ Mat imageShadow =image.clone();

int iW = imageShadow.size().width;
int iH = imageShadow.size().height;

Mat imgTmp = imageShadow.clone();

unsigned char* dataTmp = imgTmp.data;

unsigned char* data = imageShadow.data;
int channel = imageShadow.channels();
for(int i=5; i< iH-5; i++) //
{
    for(int j=5; j< iW-5; j++)
    {
        int B = data[channel*(i*iW+j)];
        int G = data[channel*(i*iW+j)+1];
        int R = data[channel*(i*iW+j)+2];
        float H;
        float S;
        float V;
        //Convert RGB to HSV
        float var_R = ( R / 255.0 ) ;                    //RGB from 0 to 255
        float var_G = ( G / 255.0 );
        float var_B = ( B / 255.0 );

        float var_Min = MIN( MIN(var_R, var_G), var_B )  ;  //Min. value of RGB
        float   var_Max = MAX( MAX(var_R, var_G), var_B )  ;  //Max. value of RGB
        float   del_Max = var_Max - var_Min      ;       //Delta RGB value 

        V = var_Max;

        if ( del_Max == 0 )                     //This is a gray, no chroma...
        {
           H = 0  ;                              //HSV results from 0 to 1
           S = 0;
        }
        else                                    //Chromatic data...
        {
           S = del_Max / var_Max;

          float del_R = ( ( ( var_Max - var_R ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
          float del_G = ( ( ( var_Max - var_G ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
          float del_B = ( ( ( var_Max - var_B ) / 6 ) + ( del_Max / 2 ) ) / del_Max;

           if      ( var_R == var_Max ) H = del_B - del_G;
           else if ( var_G == var_Max ) H = ( 1 / 3 ) + del_R - del_B;
           else if ( var_B == var_Max ) H = ( 2 / 3 ) + del_G - del_R;

           if ( H < 0 ) H += 1;
           if ( H > 1 ) H -= 1;
        }

        //if(V>0.3 && V<0.85 && H<85 && S<0.15)
        //if(V>0.5 && V<0.95 &&  S<0.2)
        if(V>0.3 && V<0.95 &&  S<0.2)
        {
            data[channel*(i*iW+j)] = 0;// dataTmp[channel*(i*iW+j)];
            data[channel*(i*iW+j)+1]=0;// dataTmp[channel*(i*iW+j)+1];
            data[channel*(i*iW+j)+2]=0;// dataTmp[channel*(i*iW+j)+2];
        }
        else
        {


            data[channel*(i*iW+j)] =  255;
            data[channel*(i*iW+j)+1]= 255;
            data[channel*(i*iW+j)+2]= 255;
        }
    }
}


//Find big area of shadow
    Mat imageGray;
cvtColor(imageShadow,imageGray,CV_RGB2GRAY);

int dilation_size =2;
 Mat element = getStructuringElement( MORPH_ELLIPSE,
                                   Size( 2*dilation_size + 1, 2*dilation_size+1 ),
                                   Point( dilation_size, dilation_size ) );

/// Apply the dilation operation to remove small areas dilate( imageGray, imageGray, element );

vector<vector<point> > contours; vector<vec4i> hierarchy;

/// Find contours findContours( imageGray, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );

vector<vector<point> > contoursResult;

for( int m = 0; m < contours.size(); m++ ) { int area = contourArea(contours[m]); if(area>400 && area < iW*iH/10) { contoursResult.push_back(contours[m]);

    }

}

}

This is my code for detect shadow:

void ShadowDetection(Mat image)
 
image)
{
Mat imageShadow =image.clone();
 
=image.clone();
int iW = imageShadow.size().width;
 int iH = imageShadow.size().height;
 Mat imgTmp = imageShadow.clone();
 unsigned char* dataTmp = imgTmp.data;
 unsigned char* data = imageShadow.data;
 int channel = imageShadow.channels();
 for(int i=5; i< iH-5; i++) //
 {
  for(int j=5; j< iW-5; j++)
 {
  int B = data[channel*(i*iW+j)];
 int G = data[channel*(i*iW+j)+1];
 int R = data[channel*(i*iW+j)+2];
 float H;
 float S;
 float V;
  //Convert RGB to HSV
  float var_R = ( R / 255.0 ) ; //RGB from 0 to 255
 float var_G = ( G / 255.0 );
 float var_B = ( B / 255.0 );
 float var_Min = MIN( MIN(var_R, var_G), var_B ) ; //Min. value of RGB
 float var_Max = MAX( MAX(var_R, var_G), var_B ) ; //Max. value of RGB
 float del_Max = var_Max - var_Min ; //Delta RGB value
 V = var_Max;
  if ( del_Max == 0 ) //This is a gray, no chroma...
 {
  H = 0 ; //HSV results from 0 to 1
 S = 0;
 }
  else //Chromatic data...
 {
  S = del_Max / var_Max;
 float del_R = ( ( ( var_Max - var_R ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
 float del_G = ( ( ( var_Max - var_G ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
 float del_B = ( ( ( var_Max - var_B ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
 if ( var_R == var_Max ) H = del_B - del_G;
  else if ( var_G == var_Max ) H = ( 1 / 3 ) + del_R - del_B;
 else if ( var_B == var_Max ) H = ( 2 / 3 ) + del_G - del_R;
 if ( H < 0 ) H += 1;
 if ( H > 1 ) H -= 1;
 }
  //if(V>0.3 && V<0.85 && H<85 && S<0.15)
 //if(V>0.5 && V<0.95 && S<0.2)
 if(V>0.3 && V<0.95 && S<0.2)
 {
  data[channel*(i*iW+j)] = 0;// dataTmp[channel*(i*iW+j)];
 data[channel*(i*iW+j)+1]=0;// dataTmp[channel*(i*iW+j)+1];
 data[channel*(i*iW+j)+2]=0;// dataTmp[channel*(i*iW+j)+2];
 }
 else
 {
 data[channel*(i*iW+j)] = 255;
  data[channel*(i*iW+j)+1]= 255;
 data[channel*(i*iW+j)+2]= 255;
 }
 }
 }
 //Find big area of shadow
 Mat imageGray;
 cvtColor(imageShadow,imageGray,CV_RGB2GRAY);
 int dilation_size =2;
 Mat element = getStructuringElement( MORPH_ELLIPSE,
  Size( 2*dilation_size + 1, 2*dilation_size+1 ),
 Point( dilation_size, dilation_size ) );
 
 /// Apply the dilation operation to remove small areas
dilate( imageGray, imageGray, element );
 
vector<vector<point> );
vector<vector<Point> > contours;
vector<vec4i> hierarchy;
 
vector<Vec4i> hierarchy;
/// Find contours
findContours( imageGray, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
 
vector<vector<point> );
vector<vector<Point> > contoursResult;
 
contoursResult;
for( int m = 0; m < contours.size(); m++ )
{
int area = contourArea(contours[m]);
if(area>400 && area < iW*iH/10)
{
contoursResult.push_back(contours[m]);
 
contoursResult.push_back(contours[m]);
 }
  }
}
  
}