Set stream position to strip offset + stripOffsetBytes after decompressing jpeg data

src/ImageSharp/Formats/Tiff/Compression/Decompressors/OldJpegTiffCompression.cs

@@ -34,9 +34,14 @@ internal sealed class OldJpegTiffCompression : TiffBaseDecompressor
 
     protected override void Decompress(BufferedReadStream stream, int byteCount, int stripHeight, Span<byte> buffer, CancellationToken cancellationToken)
     {
+        long stripOffset = stream.Position;
         stream.Position = this.startOfImageMarker;
 
         this.DecodeJpegData(stream, buffer, cancellationToken);
+
+        // Setting the stream position to the expected position.
+        // This is a workaround for some images having set the stripBytesCount not equal to the compressed jpeg data.
+        stream.Position = stripOffset + byteCount;
     }
 
     private void DecodeJpegData(BufferedReadStream stream, Span<byte> buffer, CancellationToken cancellationToken)

tests/ImageSharp.Tests/Formats/Tiff/TiffDecoderTests.cs

@@ -666,6 +666,8 @@ public class TiffDecoderTests : TiffDecoderBaseTester
 
     [Theory]
     [WithFile(RgbOldJpegCompressed, PixelTypes.Rgba32)]
+    [WithFile(RgbOldJpegCompressed2, PixelTypes.Rgba32)]
+    [WithFile(RgbOldJpegCompressed3, PixelTypes.Rgba32)]
     [WithFile(YCbCrOldJpegCompressed, PixelTypes.Rgba32)]
     public void TiffDecoder_CanDecode_OldJpegCompressed<TPixel>(TestImageProvider<TPixel> provider)
         where TPixel : unmanaged, IPixel<TPixel>

tests/ImageSharp.Tests/TestImages.cs

@@ -796,6 +796,8 @@ public static class TestImages
         public const string RgbJpegCompressed = "Tiff/rgb_jpegcompression.tiff";
         public const string RgbJpegCompressed2 = "Tiff/twain-rgb-jpeg-with-bogus-ycbcr-subsampling.tiff";
         public const string RgbOldJpegCompressed = "Tiff/OldJpegCompression.tiff";
+        public const string RgbOldJpegCompressed2 = "Tiff/OldJpegCompression2.tiff";
+        public const string RgbOldJpegCompressed3 = "Tiff/OldJpegCompression3.tiff";
         public const string YCbCrOldJpegCompressed = "Tiff/YCbCrOldJpegCompressed.tiff";
         public const string RgbWithStripsJpegCompressed = "Tiff/rgb_jpegcompressed_stripped.tiff";
         public const string RgbJpegCompressedNoJpegTable = "Tiff/rgb_jpegcompressed_nojpegtable.tiff";

tests/Images/Input/Tiff/OldJpegCompression2.tiff

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:e8f722bc322b9a7621d1d858bec36ea78d31b85221f314a2b9872d3af91d600a
+size 5052

tests/Images/Input/Tiff/OldJpegCompression3.tiff

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:4b2b73290a40c49a4a29e51ad53dadea65c1ceafc6a5384430f7092d613830db
+size 1390339