This plugin (SimpleFilters plugin) is part of the Design bundle

Where is the plugins section?

The <plugins> section is located in Web.config, and is nested inside the <resizer> element, which is nested inside <configuration>. For examples, see this sample Web.config file.

What is NuGet?

NuGet is a better way to manage your project's libraries, and is fully supported by the ImageResizer.

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Design bundle

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SimpleFilters plugin

This plugin provides grayscale, sepia, brightness, saturation, contrast, inversion, and alpha filtering options.

These filters are implemented as adjustment matrices and are processed by native code for very high performance.

Installation

Either run Install-Package ImageResizer.Plugins.SimpleFilters in the NuGet package manager, or:

Add ImageResizer.Plugins.SimpleFilters.dll to your project
Add <add name="SimpleFilters" /> inside <resizer><plugins></plugins></resizer> in Web.config.

Usage (v3.1+)

Note the order in which effects are applied MAY CHANGE in future releases

The names for these may also change in future releases

&s.grayscale=true|y|ry|ntsc|bt709|flat (true, ntsc, and y produce identical results)
&s.sepia=true
&s.alpha= 0..1
&s.brightness=-1..1
&s.contrast=-1..1
&s.saturation=-1..1
&s.invert=true

Usage (Before v3.1)

&filter=grayscale
&filter=sepia (didn't work)
&filter=brightness(.1) (-1..1) (Change .1 to the brightness offset you want)
&filter=alpha(.5) (Change .5 to the alpha multiplier you want)