Dart Image Library

Overview

The Dart Image Library provides the ability to load, save, and manipulate images in a variety of image file formats.

The library can be used with both dart:io and dart:html, for command-line, Flutter, and web applications.

NOTE: 4.0 is a major revision from the previous version of the library.

Documentation

Supported Image Formats

Read/Write

• JPG
• PNG / Animated APNG
• GIF / Animated GIF
• BMP
• TIFF
• TGA
• PVR
• ICO

Read Only

• WebP / Animated WebP
• PSD
• EXR
• PNM (PBM, PGM, PPM)

Write Only

• CUR

Examples

Create an image, set pixel values, save it to a PNG.

import'dart:io';
import'package:image/image.dart'as img;
voidmain() async {
// Create a 256x256 8-bit (default) rgb (default) image.final image = img.Image(width:256, height:256);
// Iterate over its pixelsfor (var pixel in image) {
// Set the pixels red value to its x position value, creating a gradient.
pixel..r = pixel.x
// Set the pixels green value to its y position value.
..g = pixel.y;
}
// Encode the resulting image to the PNG image format.final png = img.encodePng(image);
// Write the PNG formatted data to a file.awaitFile('image.png').writeAsBytes(png);
}

To asynchronously load an image file, resize it, and save it as a thumbnail:

import'package:image/image.dart'as img;
voidmain(List<String> args) async {
final path = args.isNotEmpty ? args[0] :'test.png';
final cmd = img.Command()
// Decode the image file at the given path
..decodeImageFile(path)
// Resize the image to a width of 64 pixels and a height that maintains the aspect ratio of the original. 
..copyResize(width:64)
// Write the image to a PNG file (determined by the suffix of the file path). 
..writeToFile('thumbnail.png');
// On platforms that support Isolates, execute the image commands asynchronously on an isolate thread.// Otherwise, the commands will be executed synchronously.await cmd.executeThread();
}