Filter effects apply graphical operations (blur, color transforms, lighting, displacement, compositing, etc.) to rendered content. A <filter> element defines a graph of filter primitives (fe*) that are applied in sequence to produce the final output.

SVG2 / Filter Effects spec: https://www.w3.org/TR/filter-effects-1/
Developer guide: SVG Filter Effects

The filter container element:

<filter> (SVGFilterElement)

Filter Primitives

All 17 SVG filter primitives have parser-backed DOM wrappers and renderer support. Most primitives are composed into a graph via the in, in2, and result attributes defined on SVGFilterPrimitiveStandardAttributes. Source primitives such as <feFlood>, <feTurbulence>, and <feImage> generate their own output; their source comes from attributes such as flood-color, procedural noise settings, or href rather than from an input image.

Filter Primitives

Blur, Shadow, and Geometry

Color and Component Transforms

Compositing and Merging

Sources: Flood, Image, Turbulence, Convolution

Lighting