Implementation of rgb2xyz in opencv using c++
I am trying to implement matlab rgb2xyz function in opencv using c++. I used cvtColor function for implementation.
But my output image is not similar to Matlab output image.Should I use any other function or operations on image ?Here is my input image ,matlab output image and my output image.
Hai... I got 1 more code for the implementation of rgb2xyz.But it gave me black output image. Here is the code.
for(int i=0;i<rn;i++)
{
for(int j=0;j<cn;j++)
{
Vec3b intensity = image.at<Vec3b>(i,j);
R= intensity.val[2];
G= intensity.val[1];
B= intensity.val[0];
r = R/255.f; //R 0..1
g = G/255.f; //G 0..1
b = B/255.f; //B 0..1
if (r <= 0.04045)
r = r/12;
else
r = (float)pow((r+0.055)/1.055,2.4);
if (g <= 0.04045)
g = g/12;
else
g = (float)pow((g+0.055)/1.055,2.4);
if (b <= 0.04045)
b = b/12;
else
b = (float)pow((b+0.055)/1.055,2.4);
X = 0.436052025f*r + 0.385081593f*g + 0.143087414f *b;
Y = 0.222491598f*r + 0.71688606f *g + 0.060621486f *b;
Z = 0.013929122f*r + 0.097097002f*g + 0.71418547f *b;
Result.at<Vec3b>(i,j)[0]=(float)X;
Result.at<Vec3b>(i,j)[1]=(float)Y;
Result.at<Vec3b>(i,j)[2]=(float)Z;
}
}
As stated in the docs, OpenCV BGR2XYZ conversion is based on D65 white point. Are you using such white point in Matlab too? Afaik, D65 is not the default illuminant in Matlab
@LorenaGdL: Sorry, I just used the matlab rgb2xyz function for generating output image.
Yes, I know, but my question is if you're using such function with specifying D65 as the whitepoint. If not, OpenCV results using cvtColor won't match Matlab ones
To solve black output:
Result.at<Vec3b>(i, j)[0] = saturate_cast<uchar>(X * 255); Result.at<Vec3b>(i, j)[1] = saturate_cast<uchar>(Y * 255); Result.at<Vec3b>(i, j)[2] = saturate_cast<uchar>(Z * 255);@LorenaGdL: My black output problem is solved.Thanks..