Lines Matching defs:sigma
35 float Blur::convertSigmaToRadius(float sigma) {
36 return sigma > 0.5f ? (sigma - 0.5f) / BLUR_SIGMA_SCALE : 0.0f;
52 * for sigma and to preserve compatibility we have kept that logic.
54 * Based on some experimental radius and sigma values we approximate the
55 * equation sigma = f(radius) as sigma = radius * 0.3 + 0.6. The larger the
57 * large sigma the gaussian curve begins to lose its shape.
68 // g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 )
70 // and sigma varies with radius.
71 float sigma = legacyConvertRadiusToSigma((float) radius);
77 float coeff1 = 1.0f / (sqrt(2.0f * pi) * sigma);
78 float coeff2 = - 1.0f / (2.0f * sigma * sigma);
