Fixed perf issues

Toolkit.Avalonia/ImageResizer.cs

@@ -6,48 +6,56 @@ namespace Toolkit.Avalonia;
 public class ImageResizer : 
     IImageResizer
 {
-    public Bitmap Resize(Stream stream, 
-        int targetWidth, 
-        int targetHeight, 
+    public Bitmap Resize(Stream stream,
+        int targetWidth,
+        int targetHeight,
         bool maintainAspectRatio)
     {
-        using SKBitmap original = SKBitmap.Decode(stream);
+        Bitmap bitmap = new(stream);
 
-        float widthRatio = (float)targetWidth / original.Width;
-        float heightRatio = (float)targetHeight / original.Height;
-        float scale = maintainAspectRatio ? Math.Max(widthRatio, heightRatio) : Math.Min(widthRatio, heightRatio);
-
-        int newWidth = (int)(original.Width * scale);
-        int newHeight = (int)(original.Height * scale);
-
-        using SKBitmap resized = new(newWidth, newHeight);
-        using SKCanvas canvas = new(resized);
-
-        canvas.Clear(SKColors.Transparent);
-        canvas.DrawBitmap(original, new SKRect(0, 0, newWidth, newHeight));
-
-        SKBitmap cropped;
-        if (maintainAspectRatio)
+        if (bitmap.Size.Width != targetWidth || bitmap.Size.Height != targetHeight)
         {
-            int cropX = (newWidth - targetWidth) / 2;
-            int cropY = (newHeight - targetHeight) / 2;
+            using SKBitmap sKBitmap = SKBitmap.Decode(stream);
+            SKBitmap? cropped = null;
+            bitmap.Dispose();
 
-            cropped = new SKBitmap(targetWidth, targetHeight);
-            using SKCanvas croppedCanvas = new(cropped);
-            SKRect cropRect = new(cropX, cropY, cropX + targetWidth, cropY + targetHeight);
-            croppedCanvas.Clear(SKColors.Transparent);
-            croppedCanvas.DrawBitmap(resized, cropRect, new SKRect(0, 0, targetWidth, targetHeight));
-        }
-        else
-        {
-            cropped = resized;
+            float widthRatio = (float)targetWidth / sKBitmap.Width;
+            float heightRatio = (float)targetHeight / sKBitmap.Height;
+            float scale = maintainAspectRatio ? Math.Max(widthRatio, heightRatio) : Math.Min(widthRatio, heightRatio);
+
+            int newWidth = (int)(sKBitmap.Width * scale);
+            int newHeight = (int)(sKBitmap.Height * scale);
+
+            using SKBitmap resized = new(newWidth, newHeight);
+            using SKCanvas canvas = new(resized);
+
+            canvas.Clear(SKColors.Transparent);
+            canvas.DrawBitmap(sKBitmap, new SKRect(0, 0, newWidth, newHeight));
+
+            if (maintainAspectRatio)
+            {
+                int cropX = (newWidth - targetWidth) / 2;
+                int cropY = (newHeight - targetHeight) / 2;
+
+                cropped = new SKBitmap(targetWidth, targetHeight);
+                using SKCanvas croppedCanvas = new(cropped);
+                SKRect cropRect = new(cropX, cropY, cropX + targetWidth, cropY + targetHeight);
+                croppedCanvas.Clear(SKColors.Transparent);
+                croppedCanvas.DrawBitmap(resized, cropRect, new SKRect(0, 0, targetWidth, targetHeight));
+            }
+            else
+            {
+                cropped = resized;
+            }
+
+            using SKImage image = SKImage.FromBitmap(cropped);
+            using MemoryStream outputStream = new();
+            image.Encode(SKEncodedImageFormat.Png, 100).SaveTo(outputStream);
+            outputStream.Seek(0, SeekOrigin.Begin);
+
+            return new Bitmap(outputStream);
         }
 
-        using SKImage image = SKImage.FromBitmap(cropped);
-        using MemoryStream outputStream = new();
-        image.Encode(SKEncodedImageFormat.Png, 100).SaveTo(outputStream);
-        outputStream.Seek(0, SeekOrigin.Begin);
-
-        return new Bitmap(outputStream);
+        return bitmap;
     }
 }