Merge pull request #1197 from SixLabors/fixForVeryLargeJpg

Change Scanlines and SamplesPerLine from short to int

src/ImageSharp/Formats/Jpeg/Components/Decoder/JpegFrame.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Six Labors and contributors.
+// Copyright (c) Six Labors and contributors.
 // Licensed under the GNU Affero General Public License, Version 3.
 
 using System;
@@ -28,12 +28,12 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder
         /// <summary>
         /// Gets or sets the number of scanlines within the frame.
         /// </summary>
-        public short Scanlines { get; set; }
+        public int Scanlines { get; set; }
 
         /// <summary>
         /// Gets or sets the number of samples per scanline.
         /// </summary>
-        public short SamplesPerLine { get; set; }
+        public int SamplesPerLine { get; set; }
 
         /// <summary>
         /// Gets or sets the number of components within a frame. In progressive frames this value can range from only 1 to 4.
@@ -105,4 +105,4 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder
             }
         }
     }
-}
+}

src/ImageSharp/Formats/Jpeg/JpegDecoderCore.cs

@@ -841,8 +841,8 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
                 Extended = frameMarker.Marker == JpegConstants.Markers.SOF1,
                 Progressive = frameMarker.Marker == JpegConstants.Markers.SOF2,
                 Precision = this.temp[0],
-                Scanlines = (short)((this.temp[1] << 8) | this.temp[2]),
-                SamplesPerLine = (short)((this.temp[3] << 8) | this.temp[4]),
+                Scanlines = (this.temp[1] << 8) | this.temp[2],
+                SamplesPerLine = (this.temp[3] << 8) | this.temp[4],
                 ComponentCount = this.temp[5]
             };