OpenCV: choosing color, intensity and texture of an image
I'm new to OpenCV and just started sifting through the API. I intend to get the color, intensity and texture values of each pixel that makes up the image. I fiddled with the structure - IplImage to get started but couldn't make much progress.
Please let me know about any means for this.
amuses
source to share
Have you tried OpenCV 2.0 ? They have a new C ++ interface that makes things easier. You can use your new Mat class to load images, access pixels efficiently, etc. This is much cleaner than IplImage. I use \ doc \ opencv.pdf as my link for everything I need. He got tutorials and examples with new C ++ interface, etc. - enough and more to get you started.
If you have more specific OpenCV questions please feel free to ask.
Here is some demo code to get you started: (I used the cv namespace):
// Load the image (looks like MATLAB :) ? )
Mat M = imread("h:\\lena.bmp");
// Display
namedWindow("Lena",CV_WINDOW_AUTOSIZE);
imshow("Lena",M);
waitKey();
// Crop out rectangle from (100,100) of size (200,200) of the red channel
const int offset[2] = {100,100};
const int dims[2] = {200,200};
Mat Red(dims[0],dims[1],CV_8UC1);
// Read it from M into Red
uchar* lena = M.data;
for(int i=0;i<dims[0];++i)
for(int j=0;j<dims[0];++j)
{
// P = i*rows*channels + j*channels + c
Red.at<uchar>(i,j) = *(lena + (i+offset[0])*M.rows*M.channels() + (j+offset[1])*M.channels()+0);
}
//Display
namedWindow("RedRect",CV_WINDOW_AUTOSIZE);
imshow("RedRect",Red);
waitKey();
source to share