React Native Image Utils

Installation 🚀🚀

$ npm install react-native-image-utils --save

or

$ yarn add react-native-image-utils

then,

$ react-native link react-native-image-utils

Android Only

1. If you do not already have openCV installed in your project, add this line to your settings.gradle

include ':openCVLibrary310'
project(':openCVLibrary310').projectDir = new File(rootProject.projectDir,'../node_modules/react-native-image-utils/android/ZdependencyZopenCVLibrary310')

2. Add below into MainApplication.java

public class MainApplication extends Application implements ReactApplication {
    ////// insert this
    static{
        System.loadLibrary("opencv_java3");
    }
    /////////////////////

Usage

Rotating(90 degrees only) images

import { transOrientRotate } from 'react-native-image-utils'

...

const outputOption = null;
const uri = 'https://i.ytimg.com/vi/YCaGYUIfdy4/maxresdefault.jpg';
const param = {
    degrees: 90
}

transOrientRotate(null, uri, param)).then((response) => {                        
                        // 'response.uri' is new path of created image
                      }).catch((err) => {
                        console.error(err)
                      });

Multiful Executions (for saving performace)

Multiful calling functions is heavy because it creates image files in each calls. Here is the way efficientious. (It runs in order.)

import { proxies } from 'react-native-image-utils'

...

const uri = 'https://i.ytimg.com/vi/YCaGYUIfdy4/maxresdefault.jpg';

const commands = []

// color scaling
commands.push({
    cmd: 'scaleCSB',
    param: {
        contrast: 50,
        saturation: 10,
        brightness: -30,
    }
})

// then, cropping
commands.push({
    cmd: 'cropPerspective',
    param: {
        topLeft: ...,
        topRight: ...,
        bottomLeft: ...,
        bottomRight: ...,
        width: ...,
        height: ...,
    }
})

// then, do something more...
commands.push({
    cmd: ...,
    param: {
        ...
    }
})

...

// You can also choose some options for output file
const OutputOption = {
    format: 'JPEG',
    quality: 0.9,
    ...
}

// Let's execute commands
// One execute to multiful commands. It creates image file just 1 time.
proxies(OutputOption, uri, commands)
.then(res => {
    // 'response.uri' is new URI of created image
})
.catch(err => {
    console.error(err)
})

Interfaces

Name	Description
cropPerspective	cropping by perspective
cropRoundedCorner	cropping rounded image
scaleCSB	scaling color by Contrast, Saturation and Brightness. (In developping. It makes different result on ios and android.)
transOrientRotate	rotating image by 90 degrees (90, 180, 270 only)
proxy	single command calling
proxies	multiful command calling

and, you can check any interfaces and parameters in index.d.ts file.

Output Options

Name	Description
format	Image file format
quality	Image quality
path	Specified path of new image file

Contribution

Welcome to anyone.