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asked 2016-02-05 07:01:10 -0600

goldroses gravatar image

Assigning uchar pixel going wrong

I want to set a pixel which meets certain criteria to 4096 (2^12), but what I end up with is 14;

        for(int j=0;j<dImg.rows;j++) 
        {
        uchar* pixrow = dImg.ptr<uchar>(j); 

        for (int i=0;i<dImg.cols;i++)
        {
            if(j == 240 && pixrow[i] ==0)  dImg.at<uchar>(j,i) = 2^12;

I check the value with

 cout<<"\nmodified: "<<endl;
for(int i = 0; i<dImg.cols;i++){
  cout<<" "<<unsigned(dImg.at<uchar>(240,i));
}

Assigning uchar pixel going wrong

I want to set a pixel which meets certain criteria to 4096 (2^12), but what I end up with is 14;

        for(int j=0;j<dImg.rows;j++) 
        {
        uchar* pixrow = dImg.ptr<uchar>(j); 

        for (int i=0;i<dImg.cols;i++)
        {
            if(j == 240 && pixrow[i] ==0)  dImg.at<uchar>(j,i) = 2^12;

also this results in cout=14: 

                if(j == 240 && pixrow[i] ==0)  pixrow[i]  = 2^12; //= 4096

I check the value with

 cout<<"\nmodified: "<<endl;
for(int i = 0; i<dImg.cols;i++){
  cout<<" "<<unsigned(dImg.at<uchar>(240,i));
}

Assigning uchar pixel going wrong

I want to set a pixel which meets certain criteria to 4096 (2^12), but what I end up with is 14;

14; Its an cv::Mat dImg in the format 16UC1 
  for(int j=0;j<dImg.rows;j++)
{
uchar* pixrow = dImg.ptr<uchar>(j); j=0;j<dimg.rows;j++) {="" uchar*="" pixrow="dImg.ptr&lt;uchar">(j); 
 
 for (int i=0;i<dImg.cols;i++)
{
if(j == 240 && pixrow[i] ==0) dImg.at<uchar>(j,i) = 2^12;

 
also this results in cout=14: 
 
                if(j == 240 && pixrow[i] ==0)  pixrow[i]  = 2^12; //= 4096

 
I check the value with
 
 cout<<"\nmodified: "<<endl;
for(int i = 0; i<dImg.cols;i++){
  cout<<" "<<unsigned(dImg.at<uchar>(240,i));
}

Assigning uchar pixel going wrong

I want to set a pixel which meets certain criteria to 4096 (2^12), but what I end up with is 14; Its an cv::Mat dImg in the format 16UC1 

        for(int j=0;j<dimg.rows;j++) {="" uchar*="" pixrow="dImg.ptr&lt;uchar">(j); 
 
j=0;j<dImg.rows;j++) 
        {
        uchar* pixrow = dImg.ptr<uchar>(j); 

        for (int i=0;i<dImg.cols;i++)
        {
            if(j == 240 && pixrow[i] ==0)  dImg.at<uchar>(j,i) = 2^12;

 
also this results in cout=14: 
 
                if(j == 240 && pixrow[i] ==0)  pixrow[i]  = 2^12; //= 4096

 
I check the value with
 
 cout<<"\nmodified: "<<endl;
for(int i = 0; i<dImg.cols;i++){
  cout<<" "<<unsigned(dImg.at<uchar>(240,i));
}

Assigning uchar pixel going wrong

I want to set a pixel which meets certain criteria to 4096 (2^12), but what I end up with is 14; Its an cv::Mat dImg in the format 16UC1 

        for(int j=0;j<dImg.rows;j++) 
        {
        uchar* pixrow = dImg.ptr<uchar>(j); 

        for (int i=0;i<dImg.cols;i++)
        {
            if(j == 240 && pixrow[i] ==0)  dImg.at<uchar>(j,i) = 2^12;

also this results in cout=14: 

                if(j == 240 && pixrow[i] ==0)  pixrow[i]  = 2^12; //= 4096

I check the value with

 cout<<"\nmodified: "<<endl;
for(int i = 0; i<dImg.cols;i++){
  cout<<" "<<unsigned(dImg.at<uchar>(240,i));
}

SOLUTION (thank your for answering)

 for(int j=0;j<dImg.rows;j++) 
    {
        ushort* pixrow = dImg.ptr<ushort>(j);  //not uchar

        for (int i=0;i<dImg.cols;i++)
        {
            if(j == 239 && pixrow[i] ==0)  pixrow[i]  = 4096;