feGaussianBlur

feGaussianBlur is a filter primitive in Scalable Vector Graphics (SVG) that applies a Gaussian blur to an input. It is used to create a blurred effect, often for softening edges, creating atmospheric effects, or simulating depth of field. The effect is achieved by convolving the input image with a Gaussian function, which distributes the blurriness based on a mathematical bell curve.

The primary attribute of feGaussianBlur is the stdDeviation. This attribute specifies the radius of the blur along the x and y axes. A higher stdDeviation value results in a more pronounced blur. The stdDeviation can be a single number, in which case it applies equally to both the x and y axes, or it can be two numbers separated by a comma, specifying individual radii for the x and y axes. For instance, stdDeviation="2" will apply a blur of radius 2 to both axes, while stdDeviation="2,4" will apply a radius of 2 along the x-axis and 4 along the y-axis.

feGaussianBlur can take another filter primitive as its input, or it can operate on the source graphic if no input is specified. It is commonly used in conjunction with other filter primitives like feMerge to combine the blurred and original images, allowing for effects such as drop shadows. The filter primitive is part of the SVG Filters specification and is widely supported by modern web browsers.