image_magick_ffi 0.0.1-dev.8

Dart bindings for ImageMagick C library which is used to edit images.

⚠️Attention⚠️

This is not a stable release. It is a development release for beta-testers to try out the plugin and report bugs. It is not recommended to use this plugin in production apps yet.

Table Of Contents

• Table Of Contents
• Contributors
• ImageMagickFFi Plugin
  • Feel Native
  • What Can It Do?
• Install
• Setup
• Usage
• Contributing
• Become a Supporter

Contributors

Special thanks to Piero5W11 for being the "FFI Master" and helping me a lot with this plugin.

ImageMagickFFi Plugin

This plugin brings to you the ImageMagick C library MagickWand to use with dart.

Feel Native

Interact with the underlying ImageMagick C api just as you used to do in C (not with pointers, of course :P).

What Can It Do?

See for yourself from this image from ImageMagick's website some of the things you can do with this plugin:

Have a look the #Usage section below for more insights.

Install

image_magick_ffi: <latest_version>

Setup

• Currently there are 4 variants of the ImageMagick library that come with this plugin: Q8, Q16,
  Q8-HDRI, and Q16-HDRI.
• You can choose which one you want to use.
• Your decision must be made at the build-time (not runtime) of your project.
• No need to worry about the files of other variants that you didn't choose in the previous step,
  only the files of the variant you had chosen will be bundled with your app when you build your
  app.

• Windows

  • Windows x64 (32 bits) and window x86 (32 bits) are both supported.
  • To choose one of the variants add this to your windows/CMakeLists.txt file:

# Use ImageMagick with Q8 and HDRI enabled.  
set(Q8 1) set(HDRI 1) 

Note:

• Do not try to set(Q8 1) and set(Q16 1) at the same time, or an error will occur.

• If you don't set any configuration then by default "Q8-No HDRI" will be used.

• Make sure you add the snippet above before this
  line include(flutter/generated_plugins.cmake)

• Android

  Currently only arm64-v8a (64 bits) is supported. If you want to help add support to armeabi-v7a ( 32 bits), have a look here .

  To choose one of the variants add this to your android/build.gradle file as a top-level statement:

// Use ImageMagick with Q16 and HDRI enabled.   
ext { Q16 = 1 HDRI = 1 }

Also note that you might need to get write permissions from the system
for some operations as writing an image.

• Linux

  Coming Soon (for sure)

• Macos

  Your contributions to provide the binaries are welcomed :)

• IOS

  Your contributions to provide the binaries are welcomed :)

Usage

Initialize a MagickWand

  @override
  void initState() {
    _wand = MagickWand.newMagickWand(); // create a MagickWand to edit images

    // set a callback to be called when image processing progress changes
    WidgetsBinding.instance.addPostFrameCallback(
      (timeStamp) async => await _wand.magickSetProgressMonitor(
        (info, offset, size, clientData) => setState(() =>
            status = '[${info.split('/').first}, $offset, $size, $clientData]'),
      ),
    );

    super.initState();
  }

Use the plugin

  // read an image, do some operations on it, then save it
Future<String> _handlePress() async {
  try {
    setState(() => isLoading = true);

    String? result;

    await _wand.magickReadImage(_inputFile!.path); // read the image
    _throwWandExceptionIfExists(_wand);

    ///////////////////////// Do Some Operations On The Wand /////////////////////////

    // resize the image
    await _wand.magickAdaptiveResizeImage(1200, 800);
    _throwWandExceptionIfExists(_wand);
    // flip the image
    await _wand.magickFlipImage();
    _throwWandExceptionIfExists(_wand);
    // enhance the image
    await _wand.magickEnhanceImage();
    _throwWandExceptionIfExists(_wand);
    // add noise to the image
    await _wand.magickAddNoiseImage(NoiseType.GaussianNoise, 1.5);
    _throwWandExceptionIfExists(_wand);

    /////////////////////////////////////////////////////////////////////////////////

    String outputFilePath = _getOutputFilePath();

    await _wand.magickWriteImage(
            outputFilePath); // write the image to a file
    _throwWandExceptionIfExists(_wand);

    _outputFile = File(outputFilePath);
    isLoading = false;
    return result ?? 'Operation Successful!';
  } catch (e) {
    _outputFile = null;
    isLoading = false;
    return 'Error: ${e.toString()}';
  }
}

String _getOutputFilePath() {
  final String ps = Platform.pathSeparator;
  final String inputFileNameWithoutExtension =
          _inputFile!.path.split(ps).last.split('.').first;
  final String outputFilePath =
          '${_outputDirectory!.path}${ps}out_$inputFileNameWithoutExtension.png';
  return outputFilePath;
}

void _throwWandExceptionIfExists(MagickWand wand) {
  MagickGetExceptionResult e =
  _wand.magickGetException(); // get the exception if any
  if (e.severity != ExceptionType.UndefinedException) {
    throw e;
  }
}

Dispose the MagickWand and the plugin

@override
dispose() {
  _wand.destroyMagickWand(); // we are done with the wand 
  disposeImageMagick(); // we are done with the whole plugin
  super.dispose();
}

• For more info about code usage, have a look at the example app in this repo, there is a complete
  working app there that is ready for you to play around with.
• Also check out
  • The official ImageMagick website.
  • ImageMagick usage documentation.
  • Fred's ImageMagick scripts.
  • Snibgo's examples.

Contributing

• Feel free to open an issue if you have any problem or suggestion.
• Feel free to open a pull request if you want to contribute.

Become a Supporter