【Flutter】图片压缩flutter_image_compress

使用第三方flutter_image_compress：https://pub.dev/packages?q=flutter_image_compress

import 'dart:io';
import 'dart:typed_data';

import 'package:flutter_image_compress/flutter_image_compress.dart';
import 'package:path_provider/path_provider.dart' as path_provider;

class ImageCompressUtil {
     
  /// 图片压缩 File -> File
  Future<File> imageCompressAndGetFile(File file) async {
     
    if (file.lengthSync() < 200 * 1024) {
     
      return file;
    }
    var quality = 100;
    if (file.lengthSync() > 4 * 1024 * 1024) {
     
      quality = 50;
    } else if (file.lengthSync() > 2 * 1024 * 1024) {
     
      quality = 60;
    } else if (file.lengthSync() > 1 * 1024 * 1024) {
     
      quality = 70;
    } else if (file.lengthSync() > 0.5 * 1024 * 1024) {
     
      quality = 80;
    } else if (file.lengthSync() > 0.25 * 1024 * 1024) {
     
      quality = 90;
    }
    var dir = await path_provider.getTemporaryDirectory();
                      var targetPath = dir.absolute.path +"/"+DateTime.now().millisecondsSinceEpoch.toString()+ ".jpg";
                      
    var result = await FlutterImageCompress.compressAndGetFile(
      file.absolute.path,
      targetPath,
      minWidth: 600,
      quality: quality,
      rotate: 0,
    );

    print("压缩后：${file.lengthSync() / 1024}");

    print("压缩后：${result.lengthSync() / 1024}");

    return result;
  }

  /// 图片压缩 File -> Uint8List
  Future<Uint8List> imageCompressFile(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;
  }

  /// 图片压缩 Asset -> Uint8List
  Future<Uint8List> imageCompressAsset(String assetName) async {
     
    var list = await FlutterImageCompress.compressAssetImage(
      assetName,
      minHeight: 1920,
      minWidth: 1080,
      quality: 96,
      rotate: 180,
    );

    return list;
  }

  /// 图片压缩 Uint8List -> Uint8List
  Future<Uint8List> testComporessList(Uint8List list) async {
     
    var result = await FlutterImageCompress.compressWithList(
      list,
      minHeight: 1920,
      minWidth: 1080,
      quality: 96,
      rotate: 135,
    );
    print(list.length);
    print(result.length);
    return result;
  }
}