Pixel-wise summation and subtraction in EmguCV -


i'm looking elegant way perform pixel-wise summation , subtraction in emgucv.

i'm trying calculate haar-like features of image. one-dimensional situation, it's done multiplying vector [x x x x x x x x] following vector element-wise:

[ 1 -1  1 -1  1 -1  1 -1] [ 1  1 -1 -1  1  1 -1 -1] [ 1  1  1  1 -1 -1 -1 -1]

so need add or subtract element pixels of image.

say,

bgr sum = new bgr(); sum = sum + img[0,0] - img[0,1] + img[0,2] - img[0,3];

obviously won't compile since there's no operator "+" in class bgr. i've make new bgr specifying each of b, g, r value, ugly.

any idea on performing elegant pixel-wise operation?

previous thread

you use img.getsum() if first flip sign of pixels want subtracted. might able multiplying image element-wise matrix consisting of 1 , -1 @ appropriate places.


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