mask2even.c

一个有关eigenface的matlab 例程

float mask2even[121] = {
 0.001080,  0.016185, -0.003095, -0.051930,  0.002255,  0.076591,  0.002255, -0.051930, -0.003095,  0.016185,  0.001080,
 0.002584,  0.038738, -0.007408, -0.124293,  0.005397,  0.183318,  0.005397, -0.124293, -0.007408,  0.038738,  0.002584,
 0.005095,  0.076365, -0.014604, -0.245024,  0.010640,  0.361381,  0.010640, -0.245024, -0.014604,  0.076365,  0.005095,
 0.008272,  0.123999, -0.023713, -0.397863,  0.017277,  0.586800,  0.017277, -0.397863, -0.023713,  0.123999,  0.008272,
 0.011065,  0.165854, -0.031717, -0.532158,  0.023108,  0.784869,  0.023108, -0.532158, -0.031717,  0.165854,  0.011065,
 0.012191,  0.182737, -0.034946, -0.586329,  0.025461,  0.864765,  0.025461, -0.586329, -0.034946,  0.182737,  0.012191,
 0.011065,  0.165854, -0.031717, -0.532158,  0.023108,  0.784869,  0.023108, -0.532158, -0.031717,  0.165854,  0.011065,
 0.008272,  0.123999, -0.023713, -0.397863,  0.017277,  0.586800,  0.017277, -0.397863, -0.023713,  0.123999,  0.008272,
 0.005095,  0.076365, -0.014604, -0.245024,  0.010640,  0.361381,  0.010640, -0.245024, -0.014604,  0.076365,  0.005095,
 0.002584,  0.038738, -0.007408, -0.124293,  0.005397,  0.183318,  0.005397, -0.124293, -0.007408,  0.038738,  0.002584,
 0.001080,  0.016185, -0.003095, -0.051931,  0.002255,  0.076591,  0.002255, -0.051931, -0.003095,  0.016185,  0.001080
};


float apply_mask2even( float* image, int imagew, int imageh, int x, int y ) { 
float returnvalue; 
int mx1 = x-( 11/2) >= 0 ? 0 : ( 11/2)-x; 
int mx2 = x+( 11/2) < imagew ? 11-1 : 11-1 - (x+( 11/2) - (imagew-1)); 
int my1 = y-( 11/2) >= 0 ? 0 : ( 11/2)-y; 
int my2 = y+( 11/2) < imageh ? 11-1 : 11-1 - (y+( 11/2) - (imageh-1)); 
int imagexoffset = x - 11/2; 
int imageyoffset = y - 11/2; 

int h , k; 
returnvalue = 0; 
for(k = my1; k <= my2; k++){ 
for(h = mx1; h <= mx2; h++){ 
returnvalue += 
mask2even[h+k* 11] * image[imagexoffset+h+imagew*(imageyoffset+k)]; 
} 
} 
return returnvalue; 
}