Mozilla's getting a new look. What do you think? https://mzl.la/brandsurvey

この記事は技術レビューを必要としています。ぜひご協力ください

この記事はまだボランティアによって 日本語 に翻訳されていません。ぜひ MDN に参加して翻訳を手伝ってください!

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

Summary

The filter property provides graphical effects like blurring, sharpening, or color shifting an element. Filters are commonly used to adjust the rendering of images, backgrounds, and borders.

Included in the CSS standard are several functions that achieve predefined effects. You can also reference an SVG filter with a URL to an SVG filter element.

Note: Older versions (4.0 through 9.0) of the Windows Internet Explorer browser supported a non-standard "filter" that has since been deprecated.

Initial valuenone
Applies toall elements; In SVG, it applies to container elements excluding the <defs> element and all graphics elements
Inheritedno
Mediavisual
Computed valueas specified
Animation typea filter function list
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Syntax

filter: url("filters.svg#filter-id");
filter: blur(5px);
filter: brightness(0.4);
filter: contrast(200%);
filter: drop-shadow(16px 16px 20px blue);
filter: grayscale(50%);
filter: hue-rotate(90deg);
filter: invert(75%);
filter: opacity(25%);
filter: saturate(30%);
filter: sepia(60%);

/* Apply multiple filters */
filter: contrast(175%) brightness(3%);

/* Global values */
filter: inherit;
filter: initial;
filter: unset;

With a function, use the following:

filter: <filter-function> [<filter-function>]* | none

For a reference to an SVG <filter> element, use the following:

filter: url(file.svg#filter-element-id) 

Interpolation

If both filters have a function list of same length without <url>, each of their filters functions is interpolated according to its specific rules. If they have different lengths, the missing equivalent filter functions from the longer list are added to the end of the shorter list using their default values, then all filter functions are interpolated according to their specific rules. If one filter is 'none', it is replaced with the filter functions list of the other one using the filter function default values, then all filter functions are interpolated according to their specific rules. Otherwise discrete interpolation is used.

Formal syntax

none | <filter-function-list>

where
<filter-function-list> = [ <filter-function> | <url> ]+

where
<filter-function> = <blur()> | <brightness()> | <contrast()> | <drop-shadow()> | <grayscale()> | <hue-rotate()> | <invert()> | <opacity()> | <sepia()> | <saturate()>

where
<blur()> = blur( <length> )
<brightness()> = brightness( <number-percentage> )
<contrast()> = contrast( [ <number-percentage> ] )
<drop-shadow()> = drop-shadow( <length>{2,3} <color>? )
<grayscale()> = grayscale( <number-percentage> )
<hue-rotate()> = hue-rotate( <angle> )
<invert()> = invert( <number-percentage> )
<opacity()> = opacity( [ <number-percentage> ] )
<sepia()> = sepia( <number-percentage> )
<saturate()> = saturate( <number-percentage> )

where
<number-percentage> = <number> | <percentage>
<color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>

where
<rgb()> = rgb( <rgb-component>#{3} )
<rgba()> = rgba( <rgb-component>#{3} , <alpha-value> )
<hsl()> = hsl( <hue>, <percentage>, <percentage> )
<hsla()> = hsla( <hue>, <percentage>, <percentage>, <alpha-value> )
<named-color> = <ident>
<deprecated-system-color> = ActiveBorder | ActiveCaption | AppWorkspace | Background | ButtonFace | ButtonHighlight | ButtonShadow | ButtonText | CaptionText | GrayText | Highlight | HighlightText | InactiveBorder | InactiveCaption | InactiveCaptionText | InfoBackground | InfoText | Menu | MenuText | Scrollbar | ThreeDDarkShadow | ThreeDFace | ThreeDHighlight | ThreeDLightShadow | ThreeDShadow | Window | WindowFrame | WindowText

where
<rgb-component> = <integer> | <percentage>
<alpha-value> = <number>
<hue> = <number>

Examples

Examples of using the predefined functions are shown below. See each function for a specific example.

.mydiv { filter: grayscale(50%) }

/* gray all images by 50% and blur by 10px */
img {
  filter: grayscale(0.5) blur(10px);
}

Examples of using the URL function with an SVG resource are shown below.

.target { filter: url(#c1); }

.mydiv { filter: url(commonfilters.xml#large-blur) }

Functions

To use the CSS filter property, you specify a value for one of the following functions. If the value is invalid, the function returns "none." Except where noted, the functions that take a value expressed with a percent sign (as in 34%) also accept the value expressed as decimal (as in 0.34).

url()

The url() function takes the location of an XML file that specifies an SVG filter, and may include an anchor to a specific filter element.

filter: url(resources.svg#c1)

blur()

Applies a Gaussian blur to the input image. The value of ‘radius’ defines the value of the standard deviation to the Gaussian function, or how many pixels on the screen blend into each other, so a larger value will create more blur. If no parameter is provided, then a value 0 is used. The parameter is specified as a CSS length, but does not accept percentage values.

filter: blur(5px)
<svg style="position: absolute; top: -99999px" xmlns="http://www.w3.org/2000/svg">
  <filter id="svgBlur" x="-5%" y="-5%" width="110%" height="110%">
    <feGaussianBlur in="SourceGraphic" stdDeviation="5"/>
  </filter>
</svg>

brightness()

Applies a linear multiplier to input image, making it appear more or less bright. A value of 0% will create an image that is completely black. A value of 100% leaves the input unchanged. Other values are linear multipliers on the effect. Values of an amount over 100% are allowed, providing brighter results. If the ‘amount’ parameter is missing, a value of 1 is used.

filter: brightness(0.5)
<svg style="position: absolute; top: -99999px" xmlns="http://www.w3.org/2000/svg">
 <filter id="brightness">
    <feComponentTransfer>
        <feFuncR type="linear" slope="[amount]"/>
        <feFuncG type="linear" slope="[amount]"/>
        <feFuncB type="linear" slope="[amount]"/>
    </feComponentTransfer>
  </filter>
</svg>

contrast()

Adjusts the contrast of the input. A value of 0% will create an image that is completely gray. A value of 100% leaves the input unchanged. Values of amount over 100% are allowed, providing results with more contrast. If the ‘amount’ parameter is missing, a value of 1 is used.

filter: contrast(200%)
<svg style="position: absolute; top: -99999px" xmlns="http://www.w3.org/2000/svg">
  <filter id="contrast">
    <feComponentTransfer>
      <feFuncR type="linear" slope="[amount]" intercept="-(0.5 * [amount]) + 0.5"/>
      <feFuncG type="linear" slope="[amount]" intercept="-(0.5 * [amount]) + 0.5"/>
      <feFuncB type="linear" slope="[amount]" intercept="-(0.5 * [amount]) + 0.5"/>
    </feComponentTransfer>
  </filter>
</svg>

drop-shadow()

Applies a drop shadow effect to the input image. A drop shadow is effectively a blurred, offset version of the input image's alpha mask drawn in a particular color, composited below the image. The function accepts a parameter of type <shadow> (defined in CSS3 Backgrounds), with the exception that the ‘inset’ keyword is not allowed. This function is similar to the more established box-shadow property; the difference is that with filters, some browsers provide hardware acceleration for better performance. The parameters of the <shadow> parameter are as follows.

<offset-x> <offset-y> (required)
These are two <length> values to set the shadow offset. <offset-x> specifies the horizontal distance. Negative values place the shadow to the left of the element. <offset-y> specifies the vertical distance. Negative values place the shadow above the element. See <length> for possible units.
If both values are 0, the shadow is placed behind the element (and may generate a blur effect if <blur-radius> and/or <spread-radius> is set).
<blur-radius> (optional)
This is a third <length> value. The larger this value, the bigger the blur, so the shadow becomes bigger and lighter. Negative values are not allowed. If not specified, it will be 0 (the shadow's edge is sharp).
<spread-radius> (optional)
This is a fourth <length> value. Positive values will cause the shadow to expand and grow bigger, and negative values will cause the shadow to shrink. If not specified, it will be 0 (the shadow will be the same size as the element). 
Note: Webkit, and maybe other browsers, do not support this 4th length; it will not render if added.
<color> (optional)
See <color> values for possible keywords and notations. If not specified, the color depends on the browser. In Gecko (Firefox), Presto (Opera) and Trident (Internet Explorer), the value of the color property is used. On the other hand, WebKit's shadow is transparent and therefore useless if <color> is omitted.
filter: drop-shadow(16px 16px 10px black)
<svg style="position: absolute; top: -999999px" xmlns="http://www.w3.org/2000/svg">
 <filter id="drop-shadow">
    <feGaussianBlur in="SourceAlpha" stdDeviation="[radius]"/>
    <feOffset dx="[offset-x]" dy="[offset-y]" result="offsetblur"/>
    <feFlood flood-color="[color]"/>
    <feComposite in2="offsetblur" operator="in"/>
    <feMerge>
      <feMergeNode/>
      <feMergeNode in="SourceGraphic"/>
    </feMerge>
  </filter>
</svg>

grayscale()

Converts the input image to grayscale. The value of ‘amount’ defines the proportion of the conversion. A value of 100% is completely grayscale. A value of 0% leaves the input unchanged. Values between 0% and 100% are linear multipliers on the effect. If the ‘amount’ parameter is missing, a value of 0 is used.

filter: grayscale(100%)

hue-rotate()

Applies a hue rotation on the input image. The value of ‘angle’ defines the number of degrees around the color circle the input samples will be adjusted. A value of 0deg leaves the input unchanged. If the ‘angle’ parameter is missing, a value of 0deg is used. Though there is no maximum value, the effect of values above 360deg wraps around.

filter: hue-rotate(90deg)
<svg style="position: absolute; top: -999999px" xmlns="http://www.w3.org/2000/svg">
  <filter id="svgHueRotate" >
    <feColorMatrix type="hueRotate" values="[angle]" />
  <filter />
</svg>

invert()

Inverts the samples in the input image. The value of ‘amount’ defines the proportion of the conversion. A value of 100% is completely inverted. A value of 0% leaves the input unchanged. Values between 0% and 100% are linear multipliers on the effect. If the ‘amount’ parameter is missing, a value of 0 is used.

filter: invert(100%)

opacity()

Applies transparency to the samples in the input image. The value of ‘amount’ defines the proportion of the conversion. A value of 0% is completely transparent. A value of 100% leaves the input unchanged. Values between 0% and 100% are linear multipliers on the effect. This is equivalent to multiplying the input image samples by amount. If the ‘amount’ parameter is missing, a value of 1 is used. This function is similar to the more established opacity property; the difference is that with filters, some browsers provide hardware acceleration for better performance.

filter: opacity(50%)

saturate()

Saturates the input image. The value of ‘amount’ defines the proportion of the conversion. A value of 0% is completely un-saturated. A value of 100% leaves the input unchanged. Other values are linear multipliers on the effect. Values of amount over 100% are allowed, providing super-saturated results. If the ‘amount’ parameter is missing, a value of 1 is used.

filter: saturate(200%)

sepia()

Converts the input image to sepia. The value of ‘amount’ defines the proportion of the conversion. A value of 100% is completely sepia. A value of 0% leaves the input unchanged. Values between 0% and 100% are linear multipliers on the effect. If the ‘amount’ parameter is missing, a value of 0 is used.

filter: sepia(100%)

Combining functions

You may combine any number of functions to manipulate the rendering. The following example enhances the contrast and brightness of the image.

filter: contrast(175%) brightness(103%)

Specifications

Specification Status Comment
Filter Effects Module Level 1
The definition of 'filter' in that specification.
Working Draft Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 18.0-webkit[1]
53.0 Unprefixed
35 (35)[2] No support[3] 15.0-webkit
40.0 Unprefixed
6.0-webkit
On SVG Elements No support[4] 35 (35) No support No support No support
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support 4.4-webkit 53.0 Unprefixed 35 (35)[2] No support 22.0-webkit
40.0 Unprefixed

6.0 (Yes)-webkit

53.0 Unprefixed
On SVG Elements No support[4] ? 35 (35) No support No support No support ?

[1] In Chrome 18 to 19, saturate() function only takes integers instead of decimal or percentage values. This bug is fixed in Chrome 20 and further.

[2] Before Firefox 34, Gecko only implemented the url() form of the filter property; as chaining was not implemented then, only one url() was allowed (or when the layout.css.filters.enabled pref is set to false).

The functional values of filter are controlled by the layout.css.filters.enabled pref and was available but disabled by default in Firefox 34.

In addition to the unprefixed support, Gecko 46.0 (Firefox 46.0 / Thunderbird 46.0 / SeaMonkey 2.43) added support for a -webkit prefixed version of the property for web compatibility reasons behind the preference layout.css.prefixes.webkit, defaulting to false. Since Gecko 49.0 (Firefox 49.0 / Thunderbird 49.0 / SeaMonkey 2.46) the preference defaults to true.

[3] Internet Explorer 4.0 to 9.0 implemented a non-standard filter property. The syntax was completely different from this one and is not documented here.

[4] Blink currently does not implement this feature. See bug 109224.

See also