image_jpeg 1.1.1 
image_jpeg: ^1.1.1 copied to clipboard
Flutter plug-in for image compression JPEG upload supports image blurring, rotation processing, and loading resource files and memory images (bytes).
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'dart:async';
import 'package:flutter/services.dart';
import 'package:image_jpeg/image_jpeg.dart';
import 'package:image_picker/image_picker.dart';
import 'package:zoomable_image/zoomable_image.dart';
import 'dart:io';
void main() => runApp(new MaterialApp(
home: MyApp(),
));
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => new _MyAppState();
}
class _MyAppState extends State<MyApp> {
String _hintMsg = '';
String _newfile;
bool _roate = false;
bool _blur = false;
Uint8List imgbuffer;
double blurValue = 1.0;
double blurZomm = 1.0;
@override
void initState() {
super.initState();
}
@override
Widget build(BuildContext context) {
var image = imgbuffer != null && !imgbuffer.isEmpty ? MemoryImage(imgbuffer) :
_newfile == null ? null : FileImageEx(File(_newfile));
return new MaterialApp(
home: new Scaffold(
appBar: new AppBar(
title: const Text('Plugin example app'),
),
body: new Center(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
SizedBox(height: 8.0),
Row(
children: <Widget>[
SizedBox(width: 16.0),
RaisedButton(onPressed: () {
_selectImage();
}, child: Text('压缩图片')),
Checkbox(value: _roate, onChanged: (v) {
setState(() {
_roate = v;
});
}),
Text('旋转'),
SizedBox(width: 8.0),
Checkbox(value: _blur, onChanged: (v) {
setState(() {
_blur = v;
});
}),
Text('高斯模糊'),
],
),
Row(
children: <Widget>[
SizedBox(width: 16.0),
Column(
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
RaisedButton(onPressed: () {
_blurImage();
}, child: Text('模糊图片')),
RaisedButton(onPressed: () {
_encodeResImage();
}, child: Text('资源图片')),
RaisedButton(onPressed: () {
_loadResImage();
}, child: Text('加载资源')),
],
),
SizedBox(width: 8.0),
Column(
children: <Widget>[
Slider(
value: blurValue,
onChanged: (v) {
setState(() {
blurValue = v;
});
},
),
Slider(
value: blurZomm,
onChanged: (v) {
setState(() {
blurZomm = v;
});
},
),
Text("$_hintMsg", style: TextStyle(
color: Colors.black,
fontSize: 11.0,
fontWeight: FontWeight.w300,
shadows: [
Shadow(blurRadius: 4.0),
]
))
],
),
SizedBox(width: 4.0),
],
),
SizedBox(height: 0.0),
Expanded(
child: GestureDetector(
child: Container(
margin: const EdgeInsets.all(2.0),
width: double.infinity,
child: image == null ? null : Image(image: image),
decoration: BoxDecoration(
border: Border.all(
color: Colors.black12,
width: 0.5,
)
),
),
onTap: imgbuffer == null && _newfile == null ? null : () {
_openNewPage(image);
},
),
)
],
),
),
),
);
}
void _openNewPage(ImageProvider image) {
Navigator.push(context, MaterialPageRoute(
builder: (context) {
return new Scaffold(
body: ZoomableImage(
image,
placeholder: const Center(child: const CircularProgressIndicator()),
backgroundColor: Colors.black,
onTap: () {
Navigator.pop(context);
},
),
);
},
));
}
_deleteLastFile(String newfile) {
if (_newfile != null && _newfile != newfile) {
File f = new File(_newfile);
f.delete();
}
_newfile = newfile;
}
_selectImage() async {
File imageFile = await ImagePicker.pickImage(source: ImageSource.gallery);
if (imageFile == null) {
print("null");
return;
}
print("srcfile: " + imageFile.path);
var t = new DateTime.now().millisecondsSinceEpoch;
String newfile = await ImageJpeg.encodeJpeg(imageFile.path, null, 65, 1360, 1360, _roate ? 90 : 0,
_blur ? (blurValue * 100).toInt() : 0, (blurZomm * 10).toInt());
var t2 = new DateTime.now().millisecondsSinceEpoch;
if (newfile == null || newfile.isEmpty) {
updateMsg("无效的图像文件");
} else {
_deleteLastFile(newfile);
imgbuffer = null;
var sv = await ImageJpeg.getInfo(imageFile.path);
var nv = await ImageJpeg.getInfo(newfile);
if (sv != null) {
updateMsg("newfile: " + newfile);
updateMsg("用时: ${t2 - t}ms \n原文件: ${getRollupSize(sv.size)}, ${sv.width}*${sv.height} \n新文件: ${getRollupSize(nv.size)}, ${nv.width}*${nv.height} \n压缩率: ${(nv.size / sv.size * 100).toStringAsFixed(2)}%");
} else
updateMsg("获取文件信息失败");
//f.delete();
}
}
_blurImage() async {
File imageFile = await ImagePicker.pickImage(source: ImageSource.gallery);
print("srcfile: " + imageFile.path);
var t = new DateTime.now().millisecondsSinceEpoch;
List<int> data = await ImageJpeg.blurImageWithFlie(imageFile.path, (blurValue * 100).toInt(), (blurZomm * 10).toInt(), _roate ? 100 : 0);
var t2 = new DateTime.now().millisecondsSinceEpoch;
if (data == null || data.isEmpty) {
updateMsg("无效的图像文件");
} else {
_deleteLastFile(null);
imgbuffer = ImageJpeg.convertToUint8List(data);
var sv = await ImageJpeg.getInfo(imageFile.path);
if (sv != null)
updateMsg("用时: ${t2 - t}ms \n图像大小: ${getRollupSize(sv.size)}, ${sv.width}*${sv.height} \n输出大小: ${getRollupSize(data == null ? 0 : data.length)}");
else
updateMsg("获取文件信息失败");
}
}
_encodeResImage() async {
var t = new DateTime.now().millisecondsSinceEpoch;
var resName = Platform.isIOS ? "test.jpg" : "test";
List<int> data = await ImageJpeg.encodeImageWithRes(resName, 70, 'drawable', 1000, 1000, _roate ? 90 : 0,
_blur ? (blurValue * 100).toInt() : 0, (blurZomm * 10).toInt());
var t2 = new DateTime.now().millisecondsSinceEpoch;
if (data == null || data.isEmpty) {
updateMsg("无效的图像文件");
} else {
_deleteLastFile(null);
imgbuffer = ImageJpeg.convertToUint8List(data);
var sv = await ImageJpeg.getResImageInfo(resName, "drawable");
if (sv != null)
updateMsg("用时: ${t2 - t}ms \n资源ID: ${sv.resId} \n图像大小: ${getRollupSize(sv.size)}, ${sv.width}*${sv.height} \n输出大小: ${getRollupSize(data == null ? 0 : data.length)}");
else
updateMsg("获取文件信息失败");
}
}
_loadResImage() async {
var t = new DateTime.now().millisecondsSinceEpoch;
var resName = Platform.isIOS ? "AppIcon" : "ic_launcher";
List<int> data = await ImageJpeg.loadResFile(resName);
var t2 = new DateTime.now().millisecondsSinceEpoch;
if (data == null || data.isEmpty) {
updateMsg("无效的图像文件");
} else {
_deleteLastFile(null);
imgbuffer = ImageJpeg.convertToUint8List(data);
var sv = await ImageJpeg.getResImageInfo(resName);
if (sv != null)
updateMsg("用时: ${t2 - t}ms \n资源ID: ${sv.resId} \n图像大小: ${getRollupSize(sv.size)}, ${sv.width}*${sv.height} \n输出大小: ${getRollupSize(data == null ? 0 : data.length)}");
else
updateMsg("获取文件信息失败");
}
}
void updateMsg(final String msg) {
print(msg);
setState(() {
_hintMsg = msg;
});
}
static const RollupSize_Units = ["GB", "MB", "KB", "B"];
/// 返回文件大小字符串
static String getRollupSize(int size) {
int idx = 3;
int r1 = 0;
String result = "";
while (idx >= 0) {
int s1 = size % 1024;
size = size >> 10;
if (size == 0 || idx == 0) {
r1 = (r1 * 100) ~/ 1024;
if (r1 > 0) {
if (r1 >= 10)
result = "$s1.$r1${RollupSize_Units[idx]}";
else
result = "$s1.0$r1${RollupSize_Units[idx]}";
} else
result = s1.toString() + RollupSize_Units[idx];
break;
}
r1 = s1;
idx--;
}
return result;
}
}
class FileImageEx extends FileImage {
int fileSize = 0;
FileImageEx(File file, { double scale = 1.0 })
: assert(file != null),
assert(scale != null),
super(file, scale: scale) {
if (file.existsSync())
fileSize = file.lengthSync();
}
@override
bool operator ==(dynamic other) {
if (other.runtimeType != runtimeType)
return false;
final FileImageEx typedOther = other;
return file?.path == typedOther.file?.path
&& scale == typedOther.scale && fileSize == typedOther.fileSize;
}
}Metadata
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popularity
Publisher
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Metadata
Flutter plug-in for image compression JPEG upload supports image blurring, rotation processing, and loading resource files and memory images (bytes).
Repository (GitHub)
View/report issues
License
MIT (LICENSE)
