it is very initial answer just to show a way to start your project.
you can try to find trained classifiers for cats. for example i found this
and tested some cat images with the code below.
#include <iostream>
#include "opencv2/highgui.hpp"
#include "opencv2/objdetect.hpp"
#include "opencv2/imgproc.hpp"
using namespace std;
using namespace cv;
int main( int argc, const char** argv )
{
if (argc < 3)
{
cerr << "usage:\n" << argv[0] << " <image_file_name> <model_file_name>" << endl;
return 0;
}
// Read in the input arguments
string model = argv[2];
CascadeClassifier detector(model);
if(detector.empty())
{
cerr << "The model could not be loaded." << endl;
}
Mat current_image, grayscale;
// Read in image and perform preprocessing
current_image = imread(argv[1]);
cvtColor(current_image, grayscale, CV_BGR2GRAY);
vector<Rect> objects;
detector.detectMultiScale(grayscale, objects, 1.05, 1);
for(int i = 0; i < objects.size(); i++)
{
rectangle(current_image, objects[i], Scalar(0, 255, 0),2);
}
imshow("result",current_image);
waitKey();
return 0;
}
some result images i get
when you find a satisfactory classifier you can use it with video frames and you can do filtering on detected cats with their colors.
also you can take a look at
cat detection using latent SVM in opencv
Black Cat Detector (no idea if it works)