Flutter视频处理插件videna的使用
Flutter视频处理插件videna的使用
Videna 是一个用于在Windows和Linux上进行视频解码和播放的Flutter库。
特性
- 将视频文件解码为帧
- 在Flutter小部件中显示帧
- 在视频中跳转到特定帧
- 获取视频元数据(时长、分辨率等)
- 支持广泛的视频格式
安装
要使用此包,在你的 pubspec.yaml
文件中添加 videna
作为依赖项:
dependencies:
videna: ^0.0.1
然后,在终端中运行以下命令以获取包:
$ flutter pub get
使用方法
将包导入到你的Dart文件中:
import 'package:videna/videna.dart';
要播放本地视频文件,可以使用 Video
小部件:
final video = Video();
video.open('path_to_video_file.mp4');
类似地,要解码视频,可以使用 VidenaPlayer
类:
final videna = VidenaPlayer(imageCallback: (videoFrame) {},
imageMetadataCallback: (videoFrameMetadata) {},
progressCallback: (progress) {});
videna.open(file: 'path_to_video_file.mp4',
speed: double.infinity,
imgFormat: ImageFormat.yuv420P);
要从视频文件中获取元数据:
MediaMetadata m;
m = getMediaMetadataSync('path_to_video_file.mp4');
// 或者
m = await getMediaMetadata('path_to_video_file.mp4');
示例
完整的示例请参阅此仓库中的 example
目录。
import 'package:flutter/services.dart';
import 'package:videna/video.dart';
import 'package:flutter/material.dart';
import 'package:file_picker/file_picker.dart';
import 'dart:io';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
Videna.initialize();
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
[@override](/user/override)
Widget build(BuildContext context) {
return MaterialApp(
title: 'Videna Example',
theme: ThemeData(
brightness: Brightness.light,
colorSchemeSeed: const Color.fromARGB(255, 178, 150, 255)),
home: const HomePage(),
);
}
}
class HomePage extends StatefulWidget {
const HomePage({super.key});
[@override](/user/override)
State<HomePage> createState() => HomePageState();
}
class HomePageState extends State<HomePage> {
int index = 0;
Uint8List? snapshotArray;
String? snapshotName;
Video video = Video();
late ProgressBarProvider progressBar;
final viewKey = GlobalKey();
[@override](/user/override)
void initState() {
progressBar = video.getProgressBar();
_init();
super.initState();
}
void _init() async {
setState(() {});
}
[@override](/user/override)
void dispose() {
super.dispose();
}
[@override](/user/override)
Widget build(BuildContext context) {
return Shortcuts(
shortcuts: {
LogicalKeySet(LogicalKeyboardKey.arrowLeft): SeekBckIntent(),
LogicalKeySet(LogicalKeyboardKey.space): ToggleIntent(),
LogicalKeySet(LogicalKeyboardKey.arrowRight): SeekFwdIntent()
},
child: Actions(
actions: {
SeekBckIntent: SeekBckAction(video, 1),
ToggleIntent: ToggleAction(video),
SeekFwdIntent: SeekFwdAction(video, 1)
},
child: Scaffold(
appBar: Tab(
child: Table(children: [
TableRow(children: [
OutlinedButton(
onPressed: () async {
FilePickerResult? result =
await FilePicker.platform.pickFiles();
if (result != null) {
await video.open(result.files.single.path!);
progressBar = video.getProgressBar();
setState(() {});
} else {}
},
child: const Text('打开文件')),
OutlinedButton(
onPressed: () {
video.takeSnapshot();
},
child: const Text('快照'),
)
])
])),
body: Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Flexible(
fit: FlexFit.loose,
child: FractionallySizedBox(
heightFactor: 0.635, child: video)),
Table(children: [
TableRow(
children: [const Row(), progressBar, const Row()]),
TableRow(children: [
backwardButtons(video),
OutlinedButton(
onPressed: () => {video.togglePause()},
child: const Icon(Icons.play_arrow)),
forwardButtons(video)
]),
])
]))));
}
}
Widget backwardButtons(Video video) {
if (Platform.isAndroid) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
OutlinedButton(
onPressed: () => {video.nFramesBackward(10)},
child: const Text('-10')),
OutlinedButton(
onPressed: () => {video.nFramesBackward(3)},
child: const Text('-3')),
OutlinedButton(
onPressed: () => {video.nFramesBackward(1)},
child: const Text('-1'))
],
);
}
return Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
OutlinedButton(
onPressed: () => {video.nFramesBackward(10)},
child: const Text('-10')),
OutlinedButton(
onPressed: () => {video.nFramesBackward(3)}, child: const Text('-3')),
OutlinedButton(
onPressed: () => {video.nFramesBackward(1)}, child: const Text('-1'))
],
);
}
Widget forwardButtons(Video video) {
if (Platform.isAndroid) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
verticalDirection: VerticalDirection.up,
children: [
OutlinedButton(
onPressed: () => {video.nFramesForward(1)},
child: const Text('1+')),
OutlinedButton(
onPressed: () => {video.nFramesForward(3)},
child: const Text('3+')),
OutlinedButton(
onPressed: () => {video.nFramesForward(10)},
child: const Text('10+')),
],
);
}
return Row(mainAxisAlignment: MainAxisAlignment.spaceEvenly, children: [
OutlinedButton(
onPressed: () => {video.nFramesForward(1)}, child: const Text('1+')),
OutlinedButton(
onPressed: () => {video.nFramesForward(3)}, child: const Text('3+')),
OutlinedButton(
onPressed: () => {video.nFramesForward(10)}, child: const Text('10+')),
]);
}
class ToggleIntent extends Intent {}
class ToggleAction extends Action<ToggleIntent> {
final Video video;
ToggleAction(this.video);
[@override](/user/override)
Object? invoke(covariant ToggleIntent intent) {
video.togglePause();
return null;
}
}
class SeekFwdIntent extends Intent {}
class SeekFwdAction extends Action<SeekFwdIntent> {
final Video video;
final int n;
SeekFwdAction(this.video, this.n);
[@override](/user/override)
Object? invoke(covariant SeekFwdIntent intent) {
video.nFramesForward(n);
return null;
}
}
class SeekBckIntent extends Intent {}
class SeekBckAction extends Action<SeekBckIntent> {
final Video video;
final int n;
SeekBckAction(this.video, this.n);
[@override](/user/override)
Object? invoke(covariant SeekBckIntent intent) {
video.nFramesBackward(n);
return null;
}
}
更多关于Flutter视频处理插件videna的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
更多关于Flutter视频处理插件videna的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
videna
是一个用于 Flutter 的视频处理插件,可以帮助你进行视频的编辑、转码、压缩、裁剪等操作。虽然 videna
并不是 Flutter 官方维护的插件,但它可能是一个社区开发的开源项目或其他第三方插件。在使用之前,请确保你了解该插件的功能、兼容性和维护状态。
以下是一个使用 videna
进行视频处理的基本步骤:
1. 添加依赖
首先,将 videna
插件添加到你的 pubspec.yaml
文件中:
dependencies:
flutter:
sdk: flutter
videna: ^版本号 # 请替换为最新版本号
然后运行 flutter pub get
来安装依赖。
2. 导入插件
在你的 Dart 文件中导入 videna
插件:
import 'package:videna/videna.dart';
3. 初始化插件
在使用 videna
之前,通常需要对其进行初始化:
await Videna.initialize();
4. 视频处理
videna
提供了多种视频处理功能,例如视频压缩、裁剪、合并等。以下是一些常见操作的示例:
视频压缩
String inputPath = '/path/to/input/video.mp4';
String outputPath = '/path/to/output/compressed_video.mp4';
await Videna.compressVideo(
inputPath: inputPath,
outputPath: outputPath,
quality: VideoQuality.medium, // 压缩质量
);
视频裁剪
String inputPath = '/path/to/input/video.mp4';
String outputPath = '/path/to/output/cropped_video.mp4';
await Videna.cropVideo(
inputPath: inputPath,
outputPath: outputPath,
startTime: Duration(seconds: 5), // 裁剪开始时间
endTime: Duration(seconds: 15), // 裁剪结束时间
);
视频合并
List<String> inputPaths = [
'/path/to/video1.mp4',
'/path/to/video2.mp4',
];
String outputPath = '/path/to/output/merged_video.mp4';
await Videna.mergeVideos(
inputPaths: inputPaths,
outputPath: outputPath,
);
5. 处理结果
处理完成后,你可以在 outputPath
指定的路径中找到处理后的视频文件。
6. 错误处理
在使用 videna
进行视频处理时,可能会遇到各种错误,例如文件不存在、权限问题等。建议在使用时进行错误处理:
try {
await Videna.compressVideo(
inputPath: inputPath,
outputPath: outputPath,
quality: VideoQuality.medium,
);
} catch (e) {
print('Error: $e');
}