# Inline undistorting an image

Hello,

I have used the OpenCV Calibration functions to create my distortion coefficients along with the camera matrix. Now, I want to take the distortion coefficients along with camera matrix to undistort a specific columns and rows in a random fashion. The reason for this is that I take the original distorted imagine and calculate a single line of columns such that I take all pixel values in a given column to arrive at a specific row weighted average.

From this, I want to remove the distortion of just this single line of X and Y(values). What specific calculation do I need to do to get this undistorted result? I don't need to go back to image pixel space, therefore everything can remain in floating point. I have tried the following, however I believe is production the distorted values because the resulting curve is in the wrong direction.

Find code snippet below: I used the equation that is contained in initundistortrectifymap removing the rectify aspects and unsuded K3,k4,5 and such.

```
void __fastcall TCamera::ProcessImage(mvIMPACT::acquire::ImageBuffer * ABuffer)
{
//Member function accepts an input image buffer and calculates a measure buffer
//The measure buffer is width*4*2, where each column contains both an row
//sum average and a sum intensity.
TBufferFrame * LBuffer;
double LDistortedX,LDistortedY;
//Distortion removal elements
double Lx;
double Ly;
double Lxy;
double LSqrX;
double LSqrY;
double LSqrD; //Square Distance (^2) also known as r2
double LSqrSqrD; //Distance (^4)
double LDestX;
double LDestY;
double LInvDen;
double Lkr;
double Lp1,Lp2;
double Lk1,Lk2;
double Lu0,Lv0;
double Lfx,Lfy;
unsigned __int32 LRowOffset;
unsigned __int32 LRow;
unsigned __int32 LColumn;
unsigned __int32 LWidth;
unsigned __int32 LHeight;
unsigned __int32 LOffset;
unsigned __int32 LXSum;
unsigned __int32 LIntensity;
unsigned __int32 LData;
union
{
void * LRawData;
unsigned __int8 * LByteData;
unsigned __int16 * LWordData;
unsigned __int32 * LDwordData;
};
if(ABuffer!=NULL)
{
LXSum = 0;
LIntensity = 0;
LRowOffset = ABuffer->iWidth;
LWidth = ABuffer->iWidth;
LHeight = ABuffer->iHeight;
LBuffer = FFrameManager->NewFrame(FFrameId);
if(LBuffer==nullptr)
return;
LRawData = ABuffer->vpData;
Lk1 = FLensModel.R[0]; //Radial coefficient 1 (k1)
Lk2 = FLensModel.R[1]; //Radial coefficient 2 (k2)
Lp1 = FLensModel.T[0]; //Tangental coefficient 1 (p1)
Lp2 = FLensModel.T[1]; //Tangental coefficient 2 (p2)
Lu0 = FLensModel.Center[0]; //Optical center X
Lv0 = FLensModel.Center[1]; //Optical center y
Lfx = FLensModel.Fx; //Camera Focal Fx
Lfy = FLensModel.Fy; //Camera Focal Fy
//First,calculate column data as XSum and Intensity.
for(LColumn=0;LColumn<LWidth;LColumn++)
{
LXSum = 0;
LIntensity = 0;
for(LRow=0;LRow<LHeight;LRow++)
{
//Assume data is mono8 for now.
LOffset = LRowOffset*LRow + LColumn;
LData = LByteData[LOffset];
if(LData>10) //Threshold of 10
{
LXSum += (LRow+1)*LData;
LIntensity += LData;
}
}
//Now, calibration the result and put into the measure record.
if(LIntensity<50)
{
LBuffer->Data[LColumn].Range = 0;
LBuffer->Data[LColumn].X = 0;
}
else
{
//Calculate the range and x.
LDistortedX = LColumn;
LDistortedY = (double)LXSum/(double)LIntensity;
Lx = (LDistortedX - Lu0)/Lfx;
Ly = (LDistortedY - Lv0)/Lfy;
Lxy = Lx*Ly;
LSqrX = Lx*Lx;
LSqrY = Ly*Ly;
LSqrD = LSqrX+LSqrY;
LSqrSqrD = LSqrD*LSqrD;
Lkr = (1.0l +((0*LSqrD + Lk2)*LSqrD + Lk1)*LSqrD);
LDestX = Lfx*(Lx*Lkr + Lp1 ...
```