rgb_to_ycbcr(1,0) = -coeff[0] * cb_fac;
rgb_to_ycbcr(1,1) = -coeff[1] * cb_fac;
rgb_to_ycbcr(1,2) = (1.0f - coeff[2]) * cb_fac;
rgb_to_ycbcr(1,0) = -coeff[0] * cb_fac;
rgb_to_ycbcr(1,1) = -coeff[1] * cb_fac;
rgb_to_ycbcr(1,2) = (1.0f - coeff[2]) * cb_fac;