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SVG filter Element

SVG Reference Complete SVG Reference

Definition and Usage

The SVG filter element is used as a container for filter effects.

Example 1

The following example shows an example of a GaussianBlur filter.

Copy the following code into Notepad and save the file as "filter_1.svg". Place the file in your Web directory:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse"
x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

Example 2

Then we add a feOffset filter:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse"
x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
<feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

Example 3

Then we add a feSpecularLighting filter:

<?xml version="1.0" standalone="no"?> <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1" xmlns="http://www.w3.org/2000/svg">

<defs> <filter id="MyFilter" filterUnits="userSpaceOnUse" x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/> <feOffset in="blur" dx="4" dy="4" result="offsetBlur"/> <feSpecularLighting in="blur" surfaceScale="5" specularConstant=".75" specularExponent="20" lighting-color="#bbbbbb" result="specOut"> <fePointLight x="-5000" y="-10000" z="20000"/> </feSpecularLighting>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

Example 4

Then we add a feComposite filter:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse"
x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
<feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>
<feSpecularLighting in="blur" surfaceScale="5"
specularConstant=".75" specularExponent="20"
lighting-color="#bbbbbb" result="specOut">
<fePointLight x="-5000" y="-10000" z="20000"/>
</feSpecularLighting>
<feComposite in="specOut" in2="SourceAlpha"
operator="in" result="specOut"/>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

Example 5

Then we add another  feComposite filter:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse"
x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
<feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>
<feSpecularLighting in="blur" surfaceScale="5"
specularConstant=".75" specularExponent="20"
lighting-color="#bbbbbb" result="specOut">
<fePointLight x="-5000" y="-10000" z="20000"/>
</feSpecularLighting>
<feComposite in="specOut" in2="SourceAlpha"
operator="in" result="specOut"/>
<feComposite in="SourceGraphic" in2="specOut"
operator="arithmetic" k1="0" k2="1" k3="1" k4="0"
result="litPaint"/>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

Example 6

Finally, we add a  feMerge filter:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg width="100%" height="100%" version="1.1"
xmlns="http://www.w3.org/2000/svg">

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse"
x="0" y="0" width="200" height="120">

<feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
<feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>
<feSpecularLighting in="blur" surfaceScale="5"
specularConstant=".75" specularExponent="20"
lighting-color="#bbbbbb" result="specOut">
<fePointLight x="-5000" y="-10000" z="20000"/>
</feSpecularLighting>
<feComposite in="specOut" in2="SourceAlpha"
operator="in" result="specOut"/>
<feComposite in="SourceGraphic" in2="specOut"
operator="arithmetic" k1="0" k2="1" k3="1" k4="0"
result="litPaint"/>
<feMerge>
<feMergeNode in="offsetBlur"/>
<feMergeNode in="litPaint"/>
</feMerge>

</filter>
</defs>

<rect x="1" y="1" width="198" height="118" fill="#cccccc" />

<g filter="url(#MyFilter)">
<path fill="none" stroke="#D90000" stroke-width="10"
d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
<text fill="#FFFFFF" stroke="black" font-size="45"
font-family="Verdana" x="52" y="76">SVG</text>
</g>

</svg>

View example

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From http://www.w3schools.com (Copyright Refsnes Data)