Feature: Bitmap RLE undefined pixel handling (SixLabors#927)

* Add bitmap decoder option, how to treat skipped pixels for RLE

* Refactored bitmap tests into smaller tests, instead of just one test which goes through all bitmap files

* Add another adobe v3 header bitmap testcase

* Using the constant from BmpConstants to Identify bitmaps

* Bitmap decoder now can handle oversized palette's

* Add test for invalid palette size

* Renamed RleUndefinedPixelHandling to RleSkippedPixelHandling

* Explicitly using SystemDrawingReferenceDecoder in some BitmapDecoder tests

* Add test cases for unsupported bitmaps

* Comparing RLE test images to reference decoder only on windows

* Add test case for decoding winv4 fast path

* Add another 8 Bit RLE test with magick reference decoder

* Optimize RLE skipped pixel handling

* Refactor RLE decoding to eliminate code duplication

* Using MagickReferenceDecoder for the 8-Bit RLE test

Author: brianpopow

tests/ImageSharp.Tests/FileTestBase.cs

@@ -28,7 +28,7 @@ public abstract class FileTestBase
         /// <summary>
         /// A collection of all the bmp test images
         /// </summary>
-        public static IEnumerable<string> AllBmpFiles = TestImages.Bmp.All;
+        public static IEnumerable<string> AllBmpFiles = TestImages.Bmp.Benchmark;
 
         /// <summary>
         /// A collection of all the jpeg test images

tests/ImageSharp.Tests/TestImages.cs

@@ -231,8 +231,15 @@ public static class Bmp
             public const string CoreHeader = "Bmp/BitmapCoreHeaderQR.bmp";
             public const string V5Header = "Bmp/BITMAPV5HEADER.bmp";
             public const string RLE8 = "Bmp/RunLengthEncoded.bmp";
+            public const string RLE8Cut = "Bmp/pal8rlecut.bmp";
+            public const string RLE8Delta = "Bmp/pal8rletrns.bmp";
+            public const string Rle8Delta320240 = "Bmp/rle8-delta-320x240.bmp";
+            public const string Rle8Blank160120 = "Bmp/rle8-blank-160x120.bmp";
+            public const string RLE8Inverted = "Bmp/RunLengthEncoded-inverted.bmp";
             public const string RLE4 = "Bmp/pal4rle.bmp";
-            public const string RLEInverted = "Bmp/RunLengthEncoded-inverted.bmp";
+            public const string RLE4Cut = "Bmp/pal4rlecut.bmp";
+            public const string RLE4Delta = "Bmp/pal4rletrns.bmp";
+            public const string Rle4Delta320240 = "Bmp/rle4-delta-320x240.bmp";
             public const string Bit1 = "Bmp/pal1.bmp";
             public const string Bit1Pal1 = "Bmp/pal1p1.bmp";
             public const string Bit4 = "Bmp/pal4.bmp";
@@ -256,15 +263,22 @@ public static class Bmp
             public const string Os2v2 = "Bmp/pal8os2v2.bmp";
             public const string LessThanFullSizedPalette = "Bmp/pal8os2sp.bmp";
             public const string Pal8Offset = "Bmp/pal8offs.bmp";
+            public const string OversizedPalette = "Bmp/pal8oversizepal.bmp";
+            public const string Rgb24LargePalette = "Bmp/rgb24largepal.bmp";
+            public const string InvalidPaletteSize = "Bmp/invalidPaletteSize.bmp";
+            public const string Rgb24jpeg = "Bmp/rgb24jpeg.bmp";
+            public const string Rgb24png = "Bmp/rgb24png.bmp";
+            public const string Rgba32v4 = "Bmp/rgba32v4.bmp";
 
-            // Bitmap images with compression type BITFIELDS
+            // Bitmap images with compression type BITFIELDS.
             public const string Rgb32bfdef = "Bmp/rgb32bfdef.bmp";
             public const string Rgb32bf = "Bmp/rgb32bf.bmp";
             public const string Rgb16bfdef = "Bmp/rgb16bfdef.bmp";
             public const string Rgb16565 = "Bmp/rgb16-565.bmp";
             public const string Rgb16565pal = "Bmp/rgb16-565pal.bmp";
             public const string Issue735 = "Bmp/issue735.bmp";
-            public const string Rgba32bf56 = "Bmp/rgba32h56.bmp";
+            public const string Rgba32bf56AdobeV3 = "Bmp/rgba32h56.bmp";
+            public const string Rgb32h52AdobeV3 = "Bmp/rgb32h52.bmp";
             public const string Rgba321010102 = "Bmp/rgba32-1010102.bmp";
             public const string RgbaAlphaBitfields = "Bmp/rgba32abf.bmp";
 
@@ -278,25 +292,32 @@ public static readonly string[] BitFields
                   Issue735,
             };
 
-            public static readonly string[] All
+            public static readonly string[] Miscellaneous
             = {
                 Car,
                 F,
-                NegHeight,
-                CoreHeader,
-                V5Header,
-                RLE4,
-                RLE8,
-                RLEInverted,
-                Bit1,
-                Bit1Pal1,
-                Bit4,
-                Bit8,
-                Bit8Inverted,
-                Bit16,
-                Bit16Inverted,
-                Bit32Rgb
+                NegHeight
             };
+
+            public static readonly string[] Benchmark
+                = {
+                          Car,
+                          F,
+                          NegHeight,
+                          CoreHeader,
+                          V5Header,
+                          RLE4,
+                          RLE8,
+                          RLE8Inverted,
+                          Bit1,
+                          Bit1Pal1,
+                          Bit4,
+                          Bit8,
+                          Bit8Inverted,
+                          Bit16,
+                          Bit16Inverted,
+                          Bit32Rgb
+                      };
         }
 
         public static class Gif