Declaration

const GaussianRadiusToSigma = 0.300386630413846;
const GaussianSigmaToRadius = 1 / GaussianRadiusToSigma;

Description

The GaussianRadiusToSigma and GaussianSigmaToRadius constants define the mathematical conversion ratio between the Gaussian kernel standard deviation $\sigma$ (Sigma) and the effective pixel radius $R$.

Because a theoretical Gaussian curve extends infinitely, Graphics32 clips the tail where kernel weights fall below one pixel precision threshold.

Conversion Formulas

• Radius to Sigma:

  $$\sigma =R\cdot \text{GaussianRadiusToSigma}$$

• Sigma to Radius:

  $$R=\sigma \cdot \text{GaussianSigmaToRadius}$$

Summary Table

Constant	Value	Description
GaussianRadiusToSigma	$0.300386630413846$	Multiplier to convert pixel blur radius $R$ to Gaussian standard deviation $\sigma$.
GaussianSigmaToRadius	$3.32904308528...$	Multiplier to convert Gaussian standard deviation $\sigma$ to pixel blur radius $R$.

See also

• Blur32
• GammaBlur32