react-native-image-filter-kit

Various image filters for iOS & Android.

Status

• iOS & Android:
  • filter components work as combinable wrappers for standard Image and ImageBackground components
  • resulting images are being cached in memory
  • additional filters can be developed as separate modules
• react-native:

  • supported versions:

    react-native	min Android SDK	min iOS version
    >=0.60.0	21	9.0
    >=0.57.1 <0.60.0	17	9.0

Installation

pod 'React', :path => '../node_modules/react-native' pod 'RNImageFilterKit', :path => '../node_modules/react-native-image-filter-kit'

pod 'React', :path => '../node_modules/react-native' pod 'RNImageFilterKit', :path => '../node_modules/react-native-image-filter-kit'

Scope

The purpose of this module is to support most of the native image filters on each platform and to provide a common interface for these filters. If the filter exists only on one platform, then its counterpart will be implemented using renderscript on Android and cikernel on iOS. If you need only color matrix filters - better use a lightweight predecessor of this module.

Example

import { Image } from 'react-native'; import {   SoftLightBlend,   Emboss,   Earlybird,   Invert,   RadialGradient } from 'react-native-image-filter-kit';  const result = (   <Earlybird     image={       <SoftLightBlend         resizeCanvasTo={'dstImage'}         dstTransform={{           scale: 'CONTAIN'         }}         dstImage={           <Emboss             image={               <Image                 style={{ width: 320, height: 320 }}                 source={require('./parrot.png')}                 resizeMode={'contain'}               />             }           />         }         srcTransform={{           anchor: { x: 0.5, y: 1 },           translate: { x: 0.5, y: 1 }         }}         srcImage={           <Invert             image={               <RadialGradient                 colors={['rgba(0, 0, 255, 1)', '#00ff00', 'red']}                 stops={[0.25, 0.75, 1]}                 center={{ x: '50w', y: '100h' }}               />             }           />         }       />     }   /> )

original image	result

filter steps

original image	Emboss	SoftLightBlend	Earlybird
RadialGradient	Invert

Reference

• Types
• Functions
• Color matrix filters
• Blur filters
• Convolve matrix filters
• Generators
• Composition filters
• Blend filters
• CSSGram filters
• Android-only filters
• iOS-only filters

Caveats

• blurRadius Image prop will not work in conjunction with this library, instead of it just use BoxBlur filter
• When running on pre-Lollipop (SDK < 21) Android devices you may experience TooManyBitmapsException, which results in image is not being rendered (this can be logged with onFilteringError prop). It looks like this is a relatively rare case which arises on low-end devices when filtering wallpaper-sized images (like 1920 × 1080 pixels). The common workarounds are:
  • using smaller images
  • using ColorMatrix filter with concatColorMatrices instead of wrapping the image with multiple color matrix based filters
  • adding android:largeHeap="true" to android/app/src/main/AndroidManifest.xml
  • replacing standard MainReactPackage with alternative one provided by this module:

      ... - import com.facebook.react.shell.MainReactPackage; + import iyegoroff.imagefilterkit.MainReactPackageWithFrescoCache;   import com.facebook.soloader.SoLoader;    import java.util.Arrays;   import java.util.List;    public class MainApplication extends Application implements ReactApplication {  +   private class MainReactPackage extends MainReactPackageWithFrescoCache {}   ...

    After this change ImageFilter will not throw TooManyBitmapsException immediately and will clear Fresco image caches, trim bitmap pool memory and try to filter the image again several times until succeed or reach the limit of retries, specified by clearCachesMaxRetries prop.
• If you are using react-native-asset - switch to iyegoroff/react-native-asset#with-key. In order to prevent unlinking of .cikernel files provided by react-native-image-filter-kit use react-native-asset the following way: npx iyegoroff/react-native-asset#with-key -a YOUR-OWN-ASSETS -k YOUR-APP-ID

Credits

• CSSGram filters are taken from cssgram project by @una
• EdgeDetection, Emboss and FuzzyGlass filters are taken from android-graphics-demo project by @chiuki
• Parrot image by Robert01
• Blend filters are based on skia sources