getImage(context), tooltip: 'Pick Image', child: new Icon(Icons.add_a_photo), ), ); } } ">

import 'dart:async';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:path/path.dart';
import 'package:photofilters/photofilters.dart';
import 'package:image/image.dart' as imageLib;
import 'package:image_picker/image_picker.dart';

void main() => runApp(new MaterialApp(home: MyApp()));

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => new _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String fileName;
  List<Filter> filters = presetFiltersList;
  File imageFile;

  Future getImage(context) async {
    imageFile = await ImagePicker.pickImage(source: ImageSource.gallery);
    fileName = basename(imageFile.path);
    var image = imageLib.decodeImage(imageFile.readAsBytesSync());
    image = imageLib.copyResize(image, width: 600);
     Map imagefile = await Navigator.push(
      context,
      new MaterialPageRoute(
        builder: (context) => new PhotoFilterSelector(
              title: Text("Photo Filter Example"),
              image: image,
              filters: presetFiltersList,
              filename: fileName,
              loader: Center(child: CircularProgressIndicator()),
              fit: BoxFit.contain,
            ),
      ),
    );
    if (imagefile != null && imagefile.containsKey('image_filtered')) {
      setState(() {
        imageFile = imagefile['image_filtered'];
      });
      print(imageFile.path);
    }
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text('Photo Filter Example'),
      ),
      body: Center(
        child: new Container(
          child: imageFile == null
              ? Center(
                  child: new Text('No image selected.'),
                )
              : Image.file(imageFile),
        ),
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: () => getImage(context),
        tooltip: 'Pick Image',
        child: new Icon(Icons.add_a_photo),
      ),
    );
  }
}

    import 'package:photofilters/filters/image_filters.dart';

    var customImageFilter = new ImageFilter(name: "Custom Image Filter");
    customImageFilter.subFilters.add(ConvolutionSubFilter.fromKernel(
      coloredEdgeDetectionKernel,
    ));
    customImageFilter.subFilters.add(ConvolutionSubFilter.fromKernel(
      gaussian7x7Kernel,
    ));
    customImageFilter.subFilters.add(ConvolutionSubFilter.fromKernel(
      sharpenKernel,
    ));
    customImageFilter.subFilters.add(ConvolutionSubFilter.fromKernel(
      highPass3x3Kernel,
    ));
    customImageFilter.subFilters.add(ConvolutionSubFilter.fromKernel(
      lowPass3x3Kernel,
    ));
    customImageFilter.subFilters.add(SaturationSubFilter(0.5));

class MyImageFilter extends ImageFilter {
  MyImageFilter(): super(name: "My Custom Image Filter") {
    this.addSubFilter(ConvolutionSubFilter.fromKernel(sharpenKernel));
  }
}

    import 'package:photofilters/filters/color_filters.dart';

    var customColorFilter = new ColorFilter(name: "Custom Color Filter");
    customColorFilter.addSubFilter(SaturationSubFilter(0.5));
    customColorFilter
        .addSubFilters([BrightnessSubFilter(0.5), HueRotationSubFilter(30)]);

class MyColorFilter extends ColorFilter {
  MyColorFilter() : super(name: "My Custom Color Filter") {
    this.addSubFilter(BrightnessSubFilter(0.8));
    this.addSubFilter(HueRotationSubFilter(30));
  }
}

class BrightnessSubFilter extends ColorSubFilter with ImageSubFilter {
  final num brightness;
  BrightnessSubFilter(this.brightness);

  ///Apply the [BrightnessSubFilter] to an Image.
  @override
  void apply(Uint8List pixels, int width, int height) =>
      image_filter_utils.brightness(pixels, brightness);

  ///Apply the [BrightnessSubFilter] to a color.
  @override
  RGBA applyFilter(RGBA color) =>
      color_filter_utils.brightness(color, brightness);
}