Ask Your Question

Revision history [back]

click to hide/show revision 1
initial version

asked 2014-05-13 15:02:09 -0600

FLY gravatar image

how to draw curve on control points

I want to draw curve on control points so that I can move the curve to change the colours , below is the code , getting help from [a very well explained answer] (http://stackoverflow.com/questions/23614037/impact-of-cubic-and-catmull-splines-on-image)

const int N=5;      // number of control points (must be >= 4)
float ctrl[N]=      // control points y values initiated with linear function y=x
{           // x value is index*1.0/(N-1)
    0.00,
    0.25,
    0.50,
    0.75,
    1.00,
 };
float correction(float col,float *ctrl,int n)
    {
    float di=1.0/float(n-1);
    int i0,i1,i2,i3;
    float t,tt,ttt;
    float a0,a1,a2,a3,d1,d2;
    // find start control point
    col*=float(n-1);
    i1=col; col-=i1;
    i0=i1-1;
    i2=i1+1; if (i2>=n) i2=n-1;
    i3=i1+2;
    // compute interpolation coefficients
    if (i0>=0) d1=0.5*(ctrl[i2]-ctrl[i0]); else d1=ctrl[i2]-ctrl[i1];
    if (i3< n) d2=0.5*(ctrl[i3]-ctrl[i1]); else d2=ctrl[i2]-ctrl[i1];
    a0=ctrl[i1];
    a1=d1;
    a2=(3.0*(ctrl[i2]-ctrl[i1]))-(2.0*d1)-d2;
    a3=d1+d2+(2.0*(-ctrl[i2]+ctrl[i1]));
    // now interpolate new colro intensity
    t=col; tt=t*t; ttt=tt*t;
    t=a0+(a1*t)+(a2*tt)+(a3*ttt);
    return t;
    }




int main (int argc, const char** argv)
{
Mat input = imread ("E:\\img2.jpg");
Mat input1 = input;
for(int i=0 ; i<input1.rows ; i++)
{
    for (int p=0;p<input1.cols;p++)
    {

        input1.at<cv::Vec3b>(i,p)[0] = 255*correction(input1.at<cv::Vec3b>(i,p)[0]/255.0,ctrl,N);  //B
        input1.at<cv::Vec3b>(i,p)[1] = 255*correction(input1.at<cv::Vec3b>(i,p)[1]/255.0,ctrl,N);  //G
        input1.at<cv::Vec3b>(i,p)[2] = 255*correction(input1.at<cv::Vec3b>(i,p)[2]/255.0,ctrl,N);  //R

    }
}

imshow("image" , input);
waitKey();

}

But the required output is like the curve

image description

how to draw curve on control points

I want to draw curve on control points so that I can move the curve to change the colours , below is the code , getting help from [a a very well explained answer] (http://stackoverflow.com/questions/23614037/impact-of-cubic-and-catmull-splines-on-image)answer

const int N=5;      // number of control points (must be >= 4)
float ctrl[N]=      // control points y values initiated with linear function y=x
{           // x value is index*1.0/(N-1)
    0.00,
    0.25,
    0.50,
    0.75,
    1.00,
 };
float correction(float col,float *ctrl,int n)
    {
    float di=1.0/float(n-1);
    int i0,i1,i2,i3;
    float t,tt,ttt;
    float a0,a1,a2,a3,d1,d2;
    // find start control point
    col*=float(n-1);
    i1=col; col-=i1;
    i0=i1-1;
    i2=i1+1; if (i2>=n) i2=n-1;
    i3=i1+2;
    // compute interpolation coefficients
    if (i0>=0) d1=0.5*(ctrl[i2]-ctrl[i0]); else d1=ctrl[i2]-ctrl[i1];
    if (i3< n) d2=0.5*(ctrl[i3]-ctrl[i1]); else d2=ctrl[i2]-ctrl[i1];
    a0=ctrl[i1];
    a1=d1;
    a2=(3.0*(ctrl[i2]-ctrl[i1]))-(2.0*d1)-d2;
    a3=d1+d2+(2.0*(-ctrl[i2]+ctrl[i1]));
    // now interpolate new colro intensity
    t=col; tt=t*t; ttt=tt*t;
    t=a0+(a1*t)+(a2*tt)+(a3*ttt);
    return t;
    }




int main (int argc, const char** argv)
{
Mat input = imread ("E:\\img2.jpg");
Mat input1 = input;
for(int i=0 ; i<input1.rows ; i++)
{
    for (int p=0;p<input1.cols;p++)
    {

        input1.at<cv::Vec3b>(i,p)[0] = 255*correction(input1.at<cv::Vec3b>(i,p)[0]/255.0,ctrl,N);  //B
        input1.at<cv::Vec3b>(i,p)[1] = 255*correction(input1.at<cv::Vec3b>(i,p)[1]/255.0,ctrl,N);  //G
        input1.at<cv::Vec3b>(i,p)[2] = 255*correction(input1.at<cv::Vec3b>(i,p)[2]/255.0,ctrl,N);  //R

    }
}

imshow("image" , input);
waitKey();

}

But the required output is like the curve

image description

how to draw curve on control points

I want to draw curve on control points so that I can move the curve to change the colours , below is the code , getting help from a very well explained answer

const int N=5;      // number of control points (must be >= 4)
float ctrl[N]=      // control points y values initiated with linear function y=x
{           // x value is index*1.0/(N-1)
    0.00,
    0.25,
    0.50,
    0.75,
    1.00,
 };
float correction(float col,float *ctrl,int n)
    {
    float di=1.0/float(n-1);
    int i0,i1,i2,i3;
    float t,tt,ttt;
    float a0,a1,a2,a3,d1,d2;
    // find start control point
    col*=float(n-1);
    i1=col; col-=i1;
    i0=i1-1;
    i2=i1+1; if (i2>=n) i2=n-1;
    i3=i1+2;
    // compute interpolation coefficients
    if (i0>=0) d1=0.5*(ctrl[i2]-ctrl[i0]); else d1=ctrl[i2]-ctrl[i1];
    if (i3< n) d2=0.5*(ctrl[i3]-ctrl[i1]); else d2=ctrl[i2]-ctrl[i1];
    a0=ctrl[i1];
    a1=d1;
    a2=(3.0*(ctrl[i2]-ctrl[i1]))-(2.0*d1)-d2;
    a3=d1+d2+(2.0*(-ctrl[i2]+ctrl[i1]));
    // now interpolate new colro intensity
    t=col; tt=t*t; ttt=tt*t;
    t=a0+(a1*t)+(a2*tt)+(a3*ttt);
    return t;
    }




int main (int argc, const char** argv)
{
Mat input = imread ("E:\\img2.jpg");
Mat input1 = input;
for(int i=0 ; i<input1.rows ; i++)
{
    for (int p=0;p<input1.cols;p++)
    {

        input1.at<cv::Vec3b>(i,p)[0] = 255*correction(input1.at<cv::Vec3b>(i,p)[0]/255.0,ctrl,N);  //B
        input1.at<cv::Vec3b>(i,p)[1] = 255*correction(input1.at<cv::Vec3b>(i,p)[1]/255.0,ctrl,N);  //G
        input1.at<cv::Vec3b>(i,p)[2] = 255*correction(input1.at<cv::Vec3b>(i,p)[2]/255.0,ctrl,N);  //R

    }
}

imshow("image" , input);
waitKey();

}

But the required output is like the curve the program is working , but the curves are not drawing on my screen like below , how to draw them using opencv or other approach

image description

how to draw curve on control points

I want to draw curve on control points so that I can move the curve to change the colours , below is the code , getting help from a very well explained answer

const int N=5;      // number of control points (must be >= 4)
float ctrl[N]=      // control points y values initiated with linear function y=x
{           // x value is index*1.0/(N-1)
    0.00,
    0.25,
    0.50,
    0.75,
    1.00,
 };
float correction(float col,float *ctrl,int n)
    {
    float di=1.0/float(n-1);
    int i0,i1,i2,i3;
    float t,tt,ttt;
    float a0,a1,a2,a3,d1,d2;
    // find start control point
    col*=float(n-1);
    i1=col; col-=i1;
    i0=i1-1;
    i2=i1+1; if (i2>=n) i2=n-1;
    i3=i1+2;
    // compute interpolation coefficients
    if (i0>=0) d1=0.5*(ctrl[i2]-ctrl[i0]); else d1=ctrl[i2]-ctrl[i1];
    if (i3< n) d2=0.5*(ctrl[i3]-ctrl[i1]); else d2=ctrl[i2]-ctrl[i1];
    a0=ctrl[i1];
    a1=d1;
    a2=(3.0*(ctrl[i2]-ctrl[i1]))-(2.0*d1)-d2;
    a3=d1+d2+(2.0*(-ctrl[i2]+ctrl[i1]));
    // now interpolate new colro intensity
    t=col; tt=t*t; ttt=tt*t;
    t=a0+(a1*t)+(a2*tt)+(a3*ttt);
    return t;
    }




int main (int argc, const char** argv)
{
Mat input = imread ("E:\\img2.jpg");
Mat input1 = input;
for(int i=0 ; i<input1.rows ; i++)
{
    for (int p=0;p<input1.cols;p++)
    {

        input1.at<cv::Vec3b>(i,p)[0] = 255*correction(input1.at<cv::Vec3b>(i,p)[0]/255.0,ctrl,N);  //B
        input1.at<cv::Vec3b>(i,p)[1] = 255*correction(input1.at<cv::Vec3b>(i,p)[1]/255.0,ctrl,N);  //G
        input1.at<cv::Vec3b>(i,p)[2] = 255*correction(input1.at<cv::Vec3b>(i,p)[2]/255.0,ctrl,N);  //R

    }
}

imshow("image" , input);
waitKey();
waitKey();}

}

But the required output is like the curve the program is working , but the curves are not drawing on my screen like below , how to draw them using opencv or other approachapproach So that these lines can play the role of their specific colour in image and with their values , like below right one is the orignal image and left one is the result of changing values through cuves , below curves are the control points per B,G,R

image description

how Merging two images showing brightness

I am trying to draw curve blend two image or you can say put one image on control points

I want to draw curve other image , when i apply blending overlay on control points so that I can move the curve to change the colours , below is the the image or simple merge two image it show me brightness in it.

here are my two images (first image is empty from inside)

and the other is

The code , getting help from a very well explained answerwhich i did is

const int N=5; main( int argc, char** argv )
{
    Mat img=imread("E:\\vig.png",-1); 
    Mat ch[4]; 
    split(img,ch);
    Mat im2 = ch[3];              // number of control points (must be >= 4)
float ctrl[N]=      here's the vignette
    im2 = 255 - im2; // control points y values initiated with linear function y=x
{           // x value is index*1.0/(N-1)
    0.00,
    0.25,
    0.50,
    0.75,
    1.00,
 };
float correction(float col,float *ctrl,int n)
    {
    float di=1.0/float(n-1);
    int i0,i1,i2,i3;
    float t,tt,ttt;
    float a0,a1,a2,a3,d1,d2;
    // find start control point
    col*=float(n-1);
    i1=col; col-=i1;
    i0=i1-1;
    i2=i1+1; if (i2>=n) i2=n-1;
    i3=i1+2;
    // compute interpolation coefficients
    if (i0>=0) d1=0.5*(ctrl[i2]-ctrl[i0]); else d1=ctrl[i2]-ctrl[i1];
    if (i3< n) d2=0.5*(ctrl[i3]-ctrl[i1]); else d2=ctrl[i2]-ctrl[i1];
    a0=ctrl[i1];
    a1=d1;
    a2=(3.0*(ctrl[i2]-ctrl[i1]))-(2.0*d1)-d2;
    a3=d1+d2+(2.0*(-ctrl[i2]+ctrl[i1]));
    // now interpolate new colro intensity
    t=col; tt=t*t; ttt=tt*t;
    t=a0+(a1*t)+(a2*tt)+(a3*ttt);
    return t;
    }




int main (int argc, const char** argv)
{
Mat input eventually cure the inversion
    Mat img2 = imread ("E:\\img2.jpg");
Mat input1 = input;
for(int i=0 ; i<input1.rows ; i++)
{
    for (int p=0;p<input1.cols;p++)
    {

        input1.at<cv::Vec3b>(i,p)[0] = 255*correction(input1.at<cv::Vec3b>(i,p)[0]/255.0,ctrl,N);  //B
        input1.at<cv::Vec3b>(i,p)[1] = 255*correction(input1.at<cv::Vec3b>(i,p)[1]/255.0,ctrl,N);  //G
        input1.at<cv::Vec3b>(i,p)[2] = 255*correction(input1.at<cv::Vec3b>(i,p)[2]/255.0,ctrl,N);  //R

    }
}

imshow("image" , input);
imread("E:\\ew.jpg");
    Mat out2;
    blending_overlay3(img2 , im2 , out2);
    imshow("image",out2);
    imwrite("E:\\image.jpg",out2);
    waitKey();}

But the required output is It show me the result like

but i require result like the curve the

EDIT

The first image is hollow/empty from center (the vignette one) , but when i read the image (vignette one) with my program is working , but the curves are then it become solid(bright) from the center , the history behind its implementation is here

There is the only problem and its with first (vignette) image reading , if it read as it is , like hollow/empty from the center , so that the other image with which we merge/blend/weight whatever apply it didn't effect the center part of the image , not drawing on my screen like below , how even show brightness etc , that's what i want to draw them using opencv or other approach So that these lines can play the role of their specific colour in image and with their values , like below right one is the orignal image and left one is the result of changing values through cuves , below curves are the control points per B,G,R

image descriptiondo

Merging two images showing brightness

I am trying to blend two image or you can say put one image on other image , when i apply blending overlay on the image or simple merge two image it show me brightness in it.

here are my two images (first image is empty from inside)inside like PS vignette)

and the other is

The code which i did is

int main( int argc, char** argv )
{
    Mat img=imread("E:\\vig.png",-1); 
    Mat ch[4]; 
    split(img,ch);
    Mat im2 = ch[3];              // here's the vignette
    im2 = 255 - im2; // eventually cure the inversion
    Mat img2 = imread("E:\\ew.jpg");
    Mat out2;
    blending_overlay3(img2 , im2 , out2);
    imshow("image",out2);
    imwrite("E:\\image.jpg",out2);
    waitKey();}

It show me the result like

but i require result like

EDIT

The first image is hollow/empty from center (the vignette one) , but when i read the image (vignette one) with my program then it become solid(bright) from the center , the history behind its implementation is here

There is the only problem and its with first (vignette) image reading , if it read as it is , like hollow/empty from the center , so that the other image with which we merge/blend/weight whatever apply it didn't effect the center part of the image , not even show brightness etc , that's what i want to do

Copyright OpenCV foundation, 2012-2018. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.
about | faq | help | privacy policy | terms of service
Powered by Askbot version 0.10.2