Add scanning QR code from image

v2rayN/ServiceLib/Common/QRCodeHelper.cs

@@ -1,4 +1,6 @@
 using QRCoder;
+using SkiaSharp;
+using ZXing.SkiaSharp;
 
 namespace ServiceLib.Common
 {
@@ -11,5 +13,78 @@ namespace ServiceLib.Common
             using PngByteQRCode qrCode = new(qrCodeData);
             return qrCode.GetGraphic(20);
         }
+
+        public static string? ParseBarcode(string? fileName)
+        {
+            if (fileName == null || !File.Exists(fileName))
+            {
+                return null;
+            }
+
+            try
+            {
+                var image = SKImage.FromEncodedData(fileName);
+                var bitmap = SKBitmap.FromImage(image);
+
+                return ReaderBarcode(bitmap);
+            }
+            catch
+            {
+                // ignored
+            }
+
+            return null;
+        }
+
+        public static string? ParseBarcode(byte[]? bytes)
+        {
+            try
+            {
+                var bitmap = SKBitmap.Decode(bytes);
+                //using var stream = new FileStream("test2.png", FileMode.Create, FileAccess.Write);
+                //using var image = SKImage.FromBitmap(bitmap);
+                //using var encodedImage = image.Encode();
+                //encodedImage.SaveTo(stream);
+                return ReaderBarcode(bitmap);
+            }
+            catch
+            {
+                // ignored
+            }
+
+            return null;
+        }
+
+        private static string? ReaderBarcode(SKBitmap? bitmap)
+        {
+            var reader = new BarcodeReader();
+            var result = reader.Decode(bitmap);
+
+            if (result != null && Utils.IsNotEmpty(result.Text))
+            {
+                return result.Text;
+            }
+
+            //FlipBitmap
+            var result2 = reader.Decode(FlipBitmap(bitmap));
+            return result2?.Text;
+        }
+
+        private static SKBitmap FlipBitmap(SKBitmap bmp)
+        {
+            // Create a bitmap (to return)
+            var flipped = new SKBitmap(bmp.Width, bmp.Height, bmp.Info.ColorType, bmp.Info.AlphaType);
+
+            // Create a canvas to draw into the bitmap
+            using var canvas = new SKCanvas(flipped);
+
+            // Set a transform matrix which moves the bitmap to the right,
+            // and then "scales" it by -1, which just flips the pixels
+            // horizontally
+            canvas.Translate(bmp.Width, 0);
+            canvas.Scale(-1, 1);
+            canvas.DrawBitmap(bmp, 0, 0);
+            return flipped;
+        }
     }
 }