React Native Image Tool

A React Native module that can process local images. Support both Android and iOS.

Function (Endlish)

• Get Image's RGBA data(array)
• Binary Image

功能 (Chinese)

• 获取图片的RGBA值（数组）
• 把图片转换成2值图

機能 (Japanese)

• 画像のRGBAデータを取得（配列）
• 元画像から、2値化画像を生成

Setup

Install the package:

• 😻 React Native >= 0.40

npm i --save react-native-image-tool
react-native link react-native-image-tool

If a java undefined error occured, add

compile project(':react-native-image-tool')

into your build.gradle

Manual linking

If your any reason you don want to link this project using 'react-native link', go to settings.gradle and add

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

then go the file that you build the ReactInstance and add the packager to it.

  ReactInstanceManager.Builder builder = ReactInstanceManager.builder()
                .setApplication(application)
                .setDefaultHardwareBackBtnHandler(application.getGAMActivity())
                .setInitialLifecycleState(LifecycleState.RESUMED)
                .setCurrentActivity((Activity) application.getGAMActivity())
                .addPackage(new ImageToolsPackage()) <------- (Add this package on the Builder list)

Usage example

import ImageTools from 'react-native-image-tool';
 
ImageTools.createBinaryImage(imageUri, type, threshold, compressFormat, quality, false, frontColorString="000000ff", backColorString="ffffffff").then((response) => {
  // response.uri is the URI of the new image that can now be displayed, uploaded...
  // response.path is the path of the new image
  // response.name is the name of the new image with the extension
  // response.size is the size of the new image
  // while bOutputBase64 is true, response.base64 is the base64 string of the new image
}).catch((err) => {
  // Oops, something went wrong. Check that the filename is correct and
  // inspect err to get more details.
});
 
ImageResizer.GetImageRGBAs(imageUri).then((response) => {
  // response.width is the URI of the new image that can now be displayed, uploaded...
  // response.height is the path of the new image
  // response.rgba is a array of image RGBA(R:bit0-7, G:bit8-15, B:bit16-23, A:bit24-32)
}).catch((err) => {
  // Oops, something went wrong. Check that the filename is correct and
  // inspect err to get more details.
});

API

promise createBinaryImage(path, type, threshold, compressFormat, quality, frontColorString="000000ff", backColorString="ffffffff")

The promise resolves with an object containing: path, uri, name and size of the new file. The URI can be used directly as the source of an <Image> component.

Option	Description
path	Path of image file, or a base64 encoded image string prefixed with 'data:image/imagetype' where imagetype is jpeg or png.
type	Only support 1 Now
threshold	0-255
compressFormat	Can be either JPEG, PNG or WEBP (android only).
quality	A number between 0 and 100. Used for the JPEG compression.
bOutputBase64	Boolean. Set output format as base64(true) or template file(false).
frontColorString	A 32bit hex formatted string with RGBA(R:bit0-7, G:bit8-15, B:bit16-23, A:bit24-32).
backColorString	A 32bit hex formatted string with RGBA(R:bit0-7, G:bit8-15, B:bit16-23, A:bit24-32).

promise GetImageRGBAs(path)

The promise resolves with an object containing: width, height and rgba. rgba is a array of RGBA data.

Option	Description
path	Path of image file, or a base64 encoded image string prefixed with 'data:image/imagetype' where imagetype is jpeg or png.