compress image with native code(objc kotlin)
This library can work on android/ios.
Q：Dart has image related libraries to compress. Why use native?
A：For reasons unknown, using dart language is not efficient, even in release version, using isolate can not solve the problem.
maybe, you need update your kotlin version to 1.2.71 or higher.
No problems found at present.
dependencies:
flutter_image_compress: ^0.2.3import 'package:flutter_image_compress/flutter_image_compress.dart';use:
Future<List<int>> testCompressFile(File file) async {
var result = await FlutterImageCompress.compressWithFile(
file.absolute.path,
minWidth: 2300,
minHeight: 1500,
quality: 94,
rotate: 90,
);
print(file.lengthSync());
print(result.length);
return result;
}
Future<File> testCompressAndGetFile(File file, String targetPath) async {
var result = await FlutterImageCompress.compressAndGetFile(
file.absolute.path, targetPath,
quality: 88,
rotate: 180,
);
print(file.lengthSync());
print(result.lengthSync());
return result;
}
Future<List<int>> testCompressAsset(String assetName) async {
var list = await FlutterImageCompress.compressAssetImage(
assetName,
minHeight: 1920,
minWidth: 1080,
quality: 96,
rotate: 180,
);
return list;
}
Future<List<int>> testComporessList(List<int> list) async {
var result = await FlutterImageCompress.compressWithList(
list,
minHeight: 1920,
minWidth: 1080,
quality: 96,
rotate: 135,
);
print(list.length);
print(result.length);
return result;
}you maybe need convert List<int> to 'Uint8List' to display image
use Uint8List need import package to your code like this
var u8 = Uint8List.fromList(list)
ImageProvider provider = MemoryImage(Uint8List.fromList(list));use in Image Widget
List<int> list = await testCompressFile(file);
ImageProvider provider = MemoryImage(Uint8List.fromList(list));
Image(
image: provider ?? AssetImage("img/img.jpg"),
),write to file
void writeToFile(List<int> list, String filePath) {
var file = File(filePath);
file.writeAsBytes(list, flush: true, mode: FileMode.write);
}Sometimes, compress method will return null. You should check you can read/write file and the parent folder of the target file must exist.
For example, use the path_provider plugin to access some application folders , use a permission plugin to request permission to access sdcard on android/iOS.
Caused by: org.gradle.internal.event.ListenerNotificationException: Failed to notify project evaluation listener.
at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:86)
...
Caused by: java.lang.AbstractMethodError
at org.jetbrains.kotlin.gradle.plugin.KotlinPluginKt.resolveSubpluginArtifacts(KotlinPlugin.kt:776)
...
see the flutter/flutter/issues#21473
you need edit your kotlin version to 1.2.71+
If flutter supports more platforms (windows, mac, linux, other) in the future and you use this library, propose issue / PR
Using this library, EXIF information will be removed.