# Implementation Run Length Smoothing Algorithm in C++

This is my old question related to RLSA in C++, but I havent got any help yet.

I tried to implement the code from Matlab to C++

The description of this algorithm :

http://crblpocr.blogspot.fr/2007/06/run-length-smoothing-algorithm-rlsa.html http://crblpocr.blogspot.fr/2007/06/determination-of-run-length-smoothing.html

There is RLSA implementation in Matlab by this thread :

http://mathworks.cn/matlabcentral/newsreader/view_thread/318198

MatLabCode

```
hor_thresh=20;
zeros_count=0;
one_flag=0;
hor_image=image;
for i=1:m
for j=1:n
if(image(i,j)==1)
if(one_flag==1)
if(zeros_count<=hor_thresh)
hor_image(i,j-zeros_count:j-1)=1;
else
one_flag=0;
end
zeros_count=0;
end
one_flag=1;
else
if(one_flag==1)
zeros_count=zeros_count+1;
end
end
end
end
```

I tried to implement in C++ Code

```
int hor_thres = 22;
int one_count = 0;
int zero_flag = 0;
Mat tmpImg = Mat(Img.size(), CV_8UC1, Scalar(0, 0, 0));
for (int j = 0; j<Img.rows; j++){
for (int i = 0; i<Img.cols; j++){
if (Img.at<uchar>(j, i) == 0)
{
if (zero_flag == 1)
{
if (one_count <= hor_thres)
{
tmpText(cv::Range(j - zero_count, j), cv::Range(i, i+1)).setTo(cv::Scalar::all(255));
// I want to do the same thing in Matlab as this image(i,j-one_count:j-1)=0;
}
else
{
zero_flag = 1;
}
one_count = 0;
}
zero_flag = 1;
}
else
{
if (zero_flag == 1)
{
one_count = one_count + 1;
}
}
}
}
```

This time no error but the result is not expected ..

The issue is the way i want to write c++ code the same thing as

Matlab

```
tmpImg(i,j-one_count:j-1)=0;
```

C++

```
tmpText(cv::Range(j - zero_count, j), cv::Range(i, i+1)).setTo(cv::Scalar::all(255));
```

Anyidea???

Another thing is in Matlab the index start from 1 while C++ start from 0.

Thank