How do you load an Image server side in dart?

Question

I've seen the answers for using an ImageElement to load an image. This only works on the browser side and I wanted to do some processing on the server.

Is there any way to load and read RGBA values from a PNG in server side dart? If not are there any server side image processing libraries planned?

Is there anyway to run Dartium "headless" so I can use the canvas api to do what I want?

Answer 1

There is a dart library that can read and write PNG images server side, http://pub.dartlang.org/packages/image

The library can read and write PNG and JPG images, and provides a number of image manipulation commands.

For example, to read a PNG, resize it, and save it to disk using this library:

import 'dart:io' as Io;
import 'package:image/image.dart';
void main() {
    // Read a PNG image from file.
    Image image = readPng(new Io.File('foo.png').readAsBytesSync());

    // Resize the image to a 120x? thumbnail (maintaining the aspect ratio).
    Image thumbnail = copyResize(image, 120);

    // Save the thumbnail to disk as a PNG.
    new Io.File('foo-thumbnail.png').writeAsBytesSync(writePng(thumbnail));
}