A Flutter package for trimming videos

Features

• Customizable video trimmer
• Video playback control
• Retrieving and storing video file

Also, supports conversion to GIF.

TRIM EDITOR

EXAMPLE APP

CUSTOMIZABLE VIDEO EDITOR

Usage

• Add the dependency video_trimmer to your pubspec.yaml file.

Android

• Go to <project root>/android/app/build.gradle and set the proper minSdkVersion, 24 for Main Release or 16 for LTS Release.

  Refer to the FFmpeg Release section.

  minSdkVersion <version>

• Go to <project root>/android/build.gradle and add the following line:

  ext.flutterFFmpegPackage = '<package name>'

  Replace the <package name> with a proper package name from the Packages List section.

iOS

• Add the following keys to your Info.plist file, located in <project root>/ios/Runner/Info.plist:

  <key>NSCameraUsageDescription</key>
  <string>Used to demonstrate image picker plugin</string>
  <key>NSMicrophoneUsageDescription</key>
  <string>Used to capture audio for image picker plugin</string>
  <key>NSPhotoLibraryUsageDescription</key>
  <string>Used to demonstrate image picker plugin</string>
  

• Set the platform version in ios/Podfile, 11.0 for Main Release or 9.3 for LTS Release.

  Refer to the FFmpeg Release section.

  platform :ios, '<version>'
  

• [Flutter >= 1.20.x] Edit ios/Podfile and add the following block before target 'Runner' do section:

  def flutter_install_ios_plugin_pods(ios_application_path = nil)
    # defined_in_file is set by CocoaPods and is a Pathname to the Podfile.
    ios_application_path ||= File.dirname(defined_in_file.realpath) if self.respond_to?(:defined_in_file)
    raise 'Could not find iOS application path' unless ios_application_path
  
    # Prepare symlinks folder. We use symlinks to avoid having Podfile.lock
    # referring to absolute paths on developers' machines.
  
    symlink_dir = File.expand_path('.symlinks', ios_application_path)
    system('rm', '-rf', symlink_dir) # Avoid the complication of dependencies like FileUtils.
  
    symlink_plugins_dir = File.expand_path('plugins', symlink_dir)
    system('mkdir', '-p', symlink_plugins_dir)
  
    plugins_file = File.join(ios_application_path, '..', '.flutter-plugins-dependencies')
    plugin_pods = flutter_parse_plugins_file(plugins_file)
    plugin_pods.each do |plugin_hash|
      plugin_name = plugin_hash['name']
      plugin_path = plugin_hash['path']
      if (plugin_name && plugin_path)
        symlink = File.join(symlink_plugins_dir, plugin_name)
        File.symlink(plugin_path, symlink)
  
        if plugin_name == 'flutter_ffmpeg'
            pod 'flutter_ffmpeg/<package name>', :path => File.join('.symlinks', 'plugins', plugin_name, 'ios')
        else
            pod plugin_name, :path => File.join('.symlinks', 'plugins', plugin_name, 'ios')
        end
      end
    end
  end
  

  Replace the <package name> with a proper package name from the Packages List section.

• [Flutter < 1.20.x] Edit ios/Podfile file and modify the default # Plugin Pods block as follows.

  # Prepare symlinks folder. We use symlinks to avoid having Podfile.lock
  # referring to absolute paths on developers' machines.
  
  system('rm -rf .symlinks')
  system('mkdir -p .symlinks/plugins')
  plugin_pods = parse_KV_file('../.flutter-plugins')
  plugin_pods.each do |name, path|
    symlink = File.join('.symlinks', 'plugins', name)
    File.symlink(path, symlink)
    if name == 'flutter_ffmpeg'
        pod name+'/<package name>', :path => File.join(symlink, 'ios')
    else
        pod name, :path => File.join(symlink, 'ios')
    end
  end
  

  Replace the <package name> with a proper package name from the Packages List section.

FFmpeg Release

In reference to the releases specified in the flutter_ffmpeg package.

	Main Release	LTS Release
Android API Level	24	16
Android Camera Access	Yes	-
Android Architectures	arm-v7a-neon arm64-v8a x86 x86-64	arm-v7a arm-v7a-neon arm64-v8a x86 x86-64
Xcode Support	10.1	7.3.1
iOS SDK	12.1	9.3
iOS Architectures	arm64 arm64e x86-64	armv7 arm64 i386 x86-64

Packages List

The following FFmpeg Packages List is in reference to the flutter_ffmpeg package.

Package	Main Release	LTS Release
min	min	min-lts
min-gpl	min-gpl	min-gpl-lts
https	https	https-lts
https-gpl	https-gpl	https-gpl-lts
audio	audio	audio-lts
video	video	video-lts
full	full	full-lts
full-gpl	full-gpl	full-gpl-lts

Functionalities

Loading input video file

final Trimmer _trimmer = Trimmer();
await _trimmer.loadVideo(videoFile: file);

Saving trimmed video

Returns a string to indicate whether the saving operation was successful.

await _trimmer
    .saveTrimmedVideo(startValue: _startValue, endValue: _endValue)
    .then((value) {
  setState(() {
    _value = value;
  });
});

Video playback state

Returns the video playback state. If true then the video is playing, otherwise it is paused.

await _trimmer.videPlaybackControl(
  startValue: _startValue,
  endValue: _endValue,
);

Advanced Command

You can use an advanced FFmpeg command if you require more customization. Just define your FFmpeg command using the ffmpegCommand property and set an output video format using customVideoFormat.

Refer to the Official FFmpeg Documentation for more information.

NOTE: Passing a wrong video format to the customVideoFormat property may result in a crash.

// Example of defining a custom command

// This is already used for creating GIF by
// default, so you do not need to use this.

await _trimmer
    .saveTrimmedVideo(
        startValue: _startValue,
        endValue: _endValue,
        ffmpegCommand:
            '-vf "fps=10,scale=480:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" -loop 0',
        customVideoFormat: '.gif')
    .then((value) {
  setState(() {
    _value = value;
  });
});

Widgets

Display a video playback area

VideoViewer()

Display the video trimmer area

TrimEditor(
  viewerHeight: 50.0,
  viewerWidth: MediaQuery.of(context).size.width,
  onChangeStart: (value) {
    _startValue = value;
  },
  onChangeEnd: (value) {
    _endValue = value;
  },
  onChangePlaybackState: (value) {
    setState(() {
      _isPlaying = value;
    });
  },
)

Example

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:video_trimmer/trim_editor.dart';
import 'package:video_trimmer/video_trimmer.dart';
import 'package:video_trimmer/video_viewer.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Video Trimmer',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: HomePage(),
    );
  }
}

class HomePage extends StatelessWidget {
  final Trimmer _trimmer = Trimmer();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Video Trimmer"),
      ),
      body: Center(
        child: Container(
          child: RaisedButton(
            child: Text("LOAD VIDEO"),
            onPressed: () async {
              File file = await ImagePicker.pickVideo(
                source: ImageSource.gallery,
              );
              if (file != null) {
                await _trimmer.loadVideo(videoFile: file);
                Navigator.of(context)
                    .push(MaterialPageRoute(builder: (context) {
                  return TrimmerView(_trimmer);
                }));
              }
            },
          ),
        ),
      ),
    );
  }
}

class TrimmerView extends StatefulWidget {
  final Trimmer _trimmer;
  TrimmerView(this._trimmer);
  @override
  _TrimmerViewState createState() => _TrimmerViewState();
}

class _TrimmerViewState extends State<TrimmerView> {
  double _startValue = 0.0;
  double _endValue = 0.0;

  bool _isPlaying = false;
  bool _progressVisibility = false;

  Future<String> _saveVideo() async {
    setState(() {
      _progressVisibility = true;
    });

    String _value;

    await widget._trimmer
        .saveTrimmedVideo(startValue: _startValue, endValue: _endValue)
        .then((value) {
      setState(() {
        _progressVisibility = false;
        _value = value;
      });
    });

    return _value;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Video Trimmer"),
      ),
      body: Builder(
        builder: (context) => Center(
          child: Container(
            padding: EdgeInsets.only(bottom: 30.0),
            color: Colors.black,
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              mainAxisSize: MainAxisSize.max,
              children: <Widget>[
                Visibility(
                  visible: _progressVisibility,
                  child: LinearProgressIndicator(
                    backgroundColor: Colors.red,
                  ),
                ),
                RaisedButton(
                  onPressed: _progressVisibility
                      ? null
                      : () async {
                          _saveVideo().then((outputPath) {
                            print('OUTPUT PATH: $outputPath');
                            final snackBar = SnackBar(content: Text('Video Saved successfully'));
                            Scaffold.of(context).showSnackBar(snackBar);
                          });
                        },
                  child: Text("SAVE"),
                ),
                Expanded(
                  child: VideoViewer(),
                ),
                Center(
                  child: TrimEditor(
                    viewerHeight: 50.0,
                    viewerWidth: MediaQuery.of(context).size.width,
                    onChangeStart: (value) {
                      _startValue = value;
                    },
                    onChangeEnd: (value) {
                      _endValue = value;
                    },
                    onChangePlaybackState: (value) {
                      setState(() {
                        _isPlaying = value;
                      });
                    },
                  ),
                ),
                FlatButton(
                  child: _isPlaying
                      ? Icon(
                          Icons.pause,
                          size: 80.0,
                          color: Colors.white,
                        )
                      : Icon(
                          Icons.play_arrow,
                          size: 80.0,
                          color: Colors.white,
                        ),
                  onPressed: () async {
                    bool playbackState =
                        await widget._trimmer.videPlaybackControl(
                      startValue: _startValue,
                      endValue: _endValue,
                    );
                    setState(() {
                      _isPlaying = playbackState;
                    });
                  },
                )
              ],
            ),
          ),
        ),
      ),
    );
  }
}

License

Copyright (c) 2020 Souvik Biswas

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.