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SVG feComponentTransfer Element

Definition and Usage

The SVG feColorMatrix element is used to perform component-wise remapping of data. It allows brightness adjustment, contrast adjustment, color balance or thresholding.

The specification of the transfer functions is defined by the sub-elements to 'feComponentTransfer':

feFuncR, transfer function for red component of the input graphic
feFuncG, transfer function for green component of the input graphic
feFuncB, transfer function for blue component of the input graphic
feFuncA, transfer function for alpha component of the input graphic

The type attribute defines the type of component transfer function. The type attribute can take one of the following values:

identity
table
discrete
linear
gamma

Example 1

The following example shows examples of four types of feComponentTransfer operations.

Copy the following code into Notepad and save the file as "fecomponenttransfer_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>
<linearGradient id="MyGrad" gradientUnits="userSpaceOnUse"
x1="50" y1="0" x2="600" y2="0">
<stop offset="0" stop-color="#ff0000" />
<stop offset=".33" stop-color="#00ff00" />
<stop offset=".67" stop-color="#0000ff" />
<stop offset="1" stop-color="#000000" />
</linearGradient>

<filter id="Identity">
<feComponentTransfer>
<feFuncR type="identity"/>
<feFuncG type="identity"/>
<feFuncB type="identity"/>
<feFuncA type="identity"/>
</feComponentTransfer>
</filter>
<filter id="Table">
<feComponentTransfer>
<feFuncR type="table" tableValues="0 0 1 1"/>
<feFuncG type="table" tableValues="1 1 0 0"/>
<feFuncB type="table" tableValues="0 1 1 0"/>
</feComponentTransfer>
</filter>
<filter id="Linear">
<feComponentTransfer>
<feFuncR type="linear" slope=".5" intercept=".25"/>
<feFuncG type="linear" slope=".5" intercept="0"/>
<feFuncB type="linear" slope=".5" intercept=".5"/>
</feComponentTransfer>
</filter>
<filter id="Gamma">
<feComponentTransfer>
<feFuncR type="gamma" amplitude="2" exponent="5" offset="0"/>
<feFuncG type="gamma" amplitude="2" exponent="3" offset="0"/>
<feFuncB type="gamma" amplitude="2" exponent="1" offset="0"/>
</feComponentTransfer>
</filter>
</defs>

<g font-size="50" font-weight="bold" fill="url(#MyGrad)">
<text x="50" y="60" filter="url(#Identity)">Identity</text>
<text x="50" y="120" filter="url(#Table)">TableLookup</text>
<text x="50" y="180" filter="url(#Linear)">LinearFunc</text>
<text x="50" y="240" filter="url(#Gamma)">GammaFunc</text>
</g>

</svg>

View example

Complete SVG Reference