From 00daabf17c8eced47a5394645ee9779b868be3a6 Mon Sep 17 00:00:00 2001
From: Krille Fear <christian-pauly@posteo.de>
Date: Sun, 12 Dec 2021 12:03:58 +0100
Subject: [PATCH] fix: Better thumbnails

This checks if the image is png or
jpg and therefore doesnt remove
transparancy. It also encodes
thumbnails with higher resolution
to make them less ugly.
---
 lib/pages/chat/send_file_dialog.dart |  2 +-
 lib/utils/resize_image.dart          | 20 ++++++++++++++------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/lib/pages/chat/send_file_dialog.dart b/lib/pages/chat/send_file_dialog.dart
index 58f1cb13..9d53f2f4 100644
--- a/lib/pages/chat/send_file_dialog.dart
+++ b/lib/pages/chat/send_file_dialog.dart
@@ -36,7 +36,7 @@ class _SendFileDialogState extends State<SendFileDialog> {
     if (file is MatrixImageFile &&
         !origImage &&
         file.bytes.length > minSizeToCompress) {
-      file = await file.resizeImage(quality: 40, max: 1200);
+      file = await file.resizeImage();
     }
     await widget.room.sendFileEventWithThumbnail(file);
   }
diff --git a/lib/utils/resize_image.dart b/lib/utils/resize_image.dart
index b048aa01..543884cb 100644
--- a/lib/utils/resize_image.dart
+++ b/lib/utils/resize_image.dart
@@ -10,8 +10,8 @@ import 'package:image/image.dart';
 import 'package:matrix/matrix.dart';
 
 extension ResizeImage on MatrixFile {
-  static const int max = 800;
-  static const int quality = 20;
+  static const int max = 1200;
+  static const int quality = 40;
 
   Future<MatrixImageFile> resizeImage({
     bool calcBlurhash = true,
@@ -23,7 +23,8 @@ extension ResizeImage on MatrixFile {
         : await compute<_ResizeBytesConfig, Uint8List>(
             resizeBytes,
             _ResizeBytesConfig(
-              this.bytes,
+              bytes: this.bytes,
+              mimeType: mimeType,
               max: max,
               quality: quality,
             ));
@@ -55,17 +56,24 @@ Future<Uint8List> resizeBytes(_ResizeBytesConfig config) async {
         : copyResize(image, height: config.max);
   }
 
-  return Uint8List.fromList(encodeJpg(image, quality: config.quality));
+  const pngMimeType = 'image/png';
+  final encoded = config.mimeType.toLowerCase() == pngMimeType
+      ? encodePng(image)
+      : encodeJpg(image, quality: config.quality);
+
+  return Uint8List.fromList(encoded);
 }
 
 class _ResizeBytesConfig {
   final Uint8List bytes;
   final int max;
   final int quality;
+  final String mimeType;
 
-  const _ResizeBytesConfig(
-    this.bytes, {
+  const _ResizeBytesConfig({
+    required this.bytes,
     this.max = ResizeImage.max,
     this.quality = ResizeImage.quality,
+    required this.mimeType,
   });
 }