Dart| Flutter How to read an image from a disk and resize a file

Sometimes, We want to read an image from a disk folder and resize it and display the image.

You can use the resized image in flutter widgets to display it

This tutorial explains how to read and resize it.

#How to read images in dart?

• First import the image library as a dependency in pubspec.yaml

name: dartapp
description: >-
   dart example application.
version: 1.0.0

environment:
  sdk: '>=2.10.0 <3.0.0'
dependencies:
  image: any

• import dart:io and image package in the applicatio

  n

• create a File object with the given file path

• Decode the image using file object using decodeImage, and convert to a byte in synchronous operation using the readAsBytesSync() method

• change the image size with copyResize and returns the image object

• File convert image object, save the object

Here is an example program for reading, resize, and outputting image

import 'dart:io' as Io;
import 'package:image/image.dart';

void main() {
  // Load a png image.
  Image image = decodeImage(new Io.File('myphoto.png').readAsBytesSync());

  Image thumbnail = copyResize(image, width: 240);

  // save as new file with new resolution
  print(new Io.File('output.png')..writeAsBytesSync(encodePng(thumbnail)));
}