<feComponentTransfer> - SVG: Scalable Vector Graphics 编辑

The <feComponentTransfer> SVG filter primitive performs color-component-wise remapping of data for each pixel. It allows operations like brightness adjustment, contrast adjustment, color balance or thresholding.

The calculations are performed on non-premultiplied color values. The colors are modified by changing each channel (R, G, B, and A) to the result of what the children <feFuncR>, <feFuncB>, <feFuncG>, and <feFuncA> return.

Usage context

Attributes

Global attributes

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

Specific attributes

• in

DOM Interface

This element implements the SVGFEComponentTransferElement interface.

Example

SVG

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 600 300">
  <defs>
    <linearGradient id="rainbow" gradientUnits="userSpaceOnUse" x1="0" y1="0" x2="100%" y2="0">
      <stop offset="0" stop-color="#ff0000"></stop>
      <stop offset="0.2" stop-color="#ffff00"></stop>
      <stop offset="0.4" stop-color="#00ff00"></stop>
      <stop offset="0.6" stop-color="#00ffff"></stop>
      <stop offset="0.8" stop-color="#0000ff"></stop>
      <stop offset="1" stop-color="#800080"></stop>
    </linearGradient>
    <filter id="identity" x="0" y="0" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="identity"></feFuncR>
        <feFuncG type="identity"></feFuncG>
        <feFuncB type="identity"></feFuncB>
        <feFuncA type="identity"></feFuncA>
      </feComponentTransfer>
    </filter>
    <filter id="table" x="0" y="0" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="table" tableValues="0 0 1 1"></feFuncR>
        <feFuncG type="table" tableValues="1 1 0 0"></feFuncG>
        <feFuncB type="table" tableValues="0 1 1 0"></feFuncB>
      </feComponentTransfer>
    </filter>
    <filter id="discrete" x="0" y="0" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="discrete" tableValues="0 0 1 1"></feFuncR>
        <feFuncG type="discrete" tableValues="1 1 0 0"></feFuncG>
        <feFuncB type="discrete" tableValues="0 1 1 0"></feFuncB>
      </feComponentTransfer>
    </filter>
    <filter id="linear" x="0" y="0" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="linear" slope="0.5" intercept="0"></feFuncR>
        <feFuncG type="linear" slope="0.5" intercept="0.25"></feFuncG>
        <feFuncB type="linear" slope="0.5" intercept="0.5"></feFuncB>
      </feComponentTransfer>
    </filter>
    <filter id="gamma" x="0" y="0" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="gamma" amplitude="4" exponent="7" offset="0"></feFuncR>
        <feFuncG type="gamma" amplitude="4" exponent="4" offset="0"></feFuncG>
        <feFuncB type="gamma" amplitude="4" exponent="1" offset="0"></feFuncB>
      </feComponentTransfer>
    </filter>
  </defs>
  <g font-weight="bold">
    <text x="0" y="20">Default</text>
    <rect x="0" y="30" width="100%" height="20"></rect>
    <text x="0" y="70">Identity</text>
    <rect x="0" y="80" width="100%" height="20" style="filter:url(#identity)"></rect>
    <text x="0" y="120">Table lookup</text>
    <rect x="0" y="130" width="100%" height="20" style="filter:url(#table)"></rect>
    <text x="0" y="170">Discrete table lookup</text>
    <rect x="0" y="180" width="100%" height="20" style="filter:url(#discrete)"></rect>
    <text x="0" y="220">Linear function</text>
    <rect x="0" y="230" width="100%" height="20" style="filter:url(#linear)"></rect>
    <text x="0" y="270">Gamma function</text>
    <rect x="0" y="280" width="100%" height="20" style="filter:url(#gamma)"></rect>
  </g>
</svg>

CSS

rect {
  fill: url(#rainbow);
}

Result

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• <filter>
• <feBlend>
• <feColorMatrix>
• <feComposite>
• <feConvolveMatrix>
• <feDiffuseLighting>
• <feDisplacementMap>
• <feFlood>
• <feFuncA>
• <feFuncB>
• <feFuncG>
• <feFuncR>
• <feGaussianBlur>
• <feImage>
• <feMerge>
• <feMorphology>
• <feOffset>
• <feSpecularLighting>
• <feTile>
• <feTurbulence>
• SVG tutorial: Filter effects