Merge pull request #321 from drewnoakes/pentax-makernote

Basic Pentax Type 2 makernote support

Author: drewnoakes

MetadataExtractor/Formats/Exif/ExifTiffHandler.cs

@@ -707,6 +707,11 @@ private bool ProcessMakernote(in TiffReaderContext context, int makernoteOffset)
                     // Always in Motorola byte order
                     TiffReader.ProcessIfd(this, context.WithByteOrder(isMotorolaByteOrder: true).WithShiftedBaseOffset(makernoteOffset), 8);
                 }
+                else if (firstTenChars.Equals("PENTAX \0II", StringComparison.Ordinal))
+                {
+                    PushDirectory(new PentaxType2MakernoteDirectory());
+                    TiffReader.ProcessIfd(this, context.WithByteOrder(isMotorolaByteOrder: false).WithShiftedBaseOffset(makernoteOffset), 10);
+                }
             }
             else if (string.Equals(firstTenChars, "Apple iOS\0", StringComparison.Ordinal))
             {

MetadataExtractor/Formats/Exif/makernotes/PentaxType2MakernoteDescriptor.cs

@@ -0,0 +1,12 @@
+// Copyright (c) Drew Noakes and contributors. All Rights Reserved. Licensed under the Apache License, Version 2.0. See LICENSE in the project root for license information.
+
+namespace MetadataExtractor.Formats.Exif.Makernotes
+{
+    public sealed class PentaxType2MakernoteDescriptor : TagDescriptor<PentaxType2MakernoteDirectory>
+    {
+        public PentaxType2MakernoteDescriptor(PentaxType2MakernoteDirectory directory)
+            : base(directory)
+        {
+        }
+    }
+}