38 lines
1.1 KiB
Dart
38 lines
1.1 KiB
Dart
import 'dart:io';
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import 'package:image/image.dart' as img;
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import 'package:path_provider/path_provider.dart';
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/// 上传前压缩：限制长边、JPEG 质量，减轻内存与带宽；解码失败时返回原文件。
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Future<File> compressImageForUpload(
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File source, {
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int maxSide = 2048,
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int jpegQuality = 85,
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}) async {
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try {
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final raw = await source.readAsBytes();
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final image = img.decodeImage(raw);
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if (image == null) return source;
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var work = image;
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if (work.width > maxSide || work.height > maxSide) {
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if (work.width >= work.height) {
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work = img.copyResize(work, width: maxSide, interpolation: img.Interpolation.linear);
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} else {
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work = img.copyResize(work, height: maxSide, interpolation: img.Interpolation.linear);
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}
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}
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final jpg = img.encodeJpg(work, quality: jpegQuality);
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final dir = await getTemporaryDirectory();
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final out = File(
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'${dir.path}/upload_${DateTime.now().millisecondsSinceEpoch}.jpg',
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);
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await out.writeAsBytes(jpg, flush: true);
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return out;
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} catch (_) {
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return source;
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}
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}
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