From 49d86e1b31f51664f8f0425879a82d8fd11aa07c Mon Sep 17 00:00:00 2001
From: Brian Popow <popow@gmx.de>
Date: Mon, 16 Aug 2021 17:40:39 +0200
Subject: [PATCH] Use buffer as span to reduce some bound checks when writing
 components

---
 src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs b/src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs
index b7a3680064..ad05b298be 100644
--- a/src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs
+++ b/src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs
@@ -642,9 +642,10 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
                 int i3 = 3 * i;
 
                 // Component ID.
-                this.buffer[i3 + 6] = componentIds[i];
-                this.buffer[i3 + 7] = subsamples[i];
-                this.buffer[i3 + 8] = chroma[i];
+                Span<byte> bufferSpan = this.buffer.AsSpan(i3 + 6, 3);
+                bufferSpan[2] = chroma[i];
+                bufferSpan[1] = subsamples[i];
+                bufferSpan[0] = componentIds[i];
             }
 
             this.outputStream.Write(this.buffer, 0, (3 * (componentCount - 1)) + 9);