Merge branch 'master' into bp/dofiltersse2

src/ImageSharp/Formats/Jpeg/Components/Encoder/HuffmanScanEncoder.cs

@@ -650,6 +650,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Encoder
             }
 
             this.target.Write(this.streamWriteBuffer, 0, writeIdx);
+            this.emitWriteIndex = this.emitBuffer.Length;
         }
 
         /// <summary>
@@ -660,11 +661,8 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Encoder
         /// This must be called only if <see cref="IsStreamFlushNeeded"/> is true
         /// only during the macroblocks encoding routine.
         /// </remarks>
-        private void FlushToStream()
-        {
+        private void FlushToStream() =>
             this.FlushToStream(this.emitWriteIndex * 4);
-            this.emitWriteIndex = this.emitBuffer.Length;
-        }
 
         /// <summary>
         /// Flushes final cached bits to the stream padding 1's to
@@ -681,10 +679,11 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Encoder
             // And writing only valuable count of bytes count we want to write to the output stream
             int valuableBytesCount = (int)Numerics.DivideCeil((uint)this.bitCount, 8);
             uint packedBytes = this.accumulatedBits | (uint.MaxValue >> this.bitCount);
-            this.emitBuffer[--this.emitWriteIndex] = packedBytes;
+            this.emitBuffer[this.emitWriteIndex - 1] = packedBytes;
 
             // Flush cached bytes to the output stream with padding bits
-            this.FlushToStream((this.emitWriteIndex * 4) - 4 + valuableBytesCount);
+            int lastByteIndex = (this.emitWriteIndex * 4) - valuableBytesCount;
+            this.FlushToStream(lastByteIndex);
         }
     }
 }