<feMorphology>

The <feMorphology> SVG filter primitive is used to erode or dilate the input image. It's usefulness lies especially in fattening or thinning effects.

Usage context

Attributes

Global attributes

• Core attributes
• Presentation attributes
• Filter primitive attributes
• class
• style

Specific attributes

• in
• operator
• radius

DOM Interface

This element implements the SVGFEMorphologyElement interface.

Filtering SVG content

SVG

<svg xmlns="http://www.w3.org/2000/svg" width="300" height="180">
  <filter id="erode">
    <feMorphology operator="erode" radius="1"/>
  </filter>
  <filter id="dilate">
    <feMorphology operator="dilate" radius="2"/>
  </filter>
  <text y="1em">Normal text</text>
  <text id="thin" y="2em">Thinned text</text>
  <text id="thick" y="3em">Fattened text</text>
</svg>

CSS

text {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 3em;
}

#thin {
  filter: url(#erode);
}

#thick {
  filter: url(#dilate);
}

Filtering HTML content

SVG

<svg xmlns="http://www.w3.org/2000/svg" width="0" height="0">
  <filter id="erode">
    <feMorphology operator="erode" radius="1"/>
  </filter>
  <filter id="dilate">
    <feMorphology operator="dilate" radius="2"/>
  </filter>
</svg>

<p>Normal text</p>
<p id="thin">Thinned text</p>
<p id="thick">Fattened text</p>

CSS

p {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 3em;
}

#thin {
  filter: url(#erode);
}

#thick {
  filter: url(#dilate);
}

Specifications

Browser compatibility

See also

• <filter>
• <animate>
• <set>
• <feBlend>
• <feColorMatrix>
• <feComponentTransfer>
• <feComposite>
• <feConvolveMatrix>
• <feDiffuseLighting>
• <feDisplacementMap>
• <feFlood>
• <feGaussianBlur>
• <feImage>
• <feMerge>
• <feOffset>
• <feSpecularLighting>
• <feTile>
• <feTurbulence>
• SVG tutorial: Filter effects