Don't use Linq and test for common path first.

JimBobSquarePants · JimBobSquarePants · commit 8464a3d44884 · 2020-10-29T15:21:52.000Z
diff --git a/src/ImageSharp/Image{TPixel}.cs b/src/ImageSharp/Image{TPixel}.cs
@@ -201,14 +201,14 @@ public Span<TPixel> GetPixelRowSpan(int rowIndex)
         public bool TryGetSinglePixelSpan(out Span<TPixel> span)
         {
             IMemoryGroup<TPixel> mg = this.GetPixelMemoryGroup();
-            if (mg.Count > 1)
+            if (mg.Count == 1)
             {
-                span = default;
-                return false;
+                span = mg[0].Span;
+                return true;
             }
 
-            span = mg.Single().Span;
-            return true;
+            span = default;
+            return false;
         }
 
         /// <summary>

Original file line number	Diff line number	Diff line change
`@@ -201,14 +201,14 @@ public Span<TPixel> GetPixelRowSpan(int rowIndex)`
`201`	`201`	`public bool TryGetSinglePixelSpan(out Span<TPixel> span)`
`202`	`202`	`{`
`203`	`203`	`IMemoryGroup<TPixel> mg = this.GetPixelMemoryGroup();`
`204`		`- if (mg.Count > 1)`
	`204`	`+ if (mg.Count == 1)`
`205`	`205`	`{`
`206`		`- span = default;`
`207`		`- return false;`
	`206`	`+ span = mg[0].Span;`
	`207`	`+ return true;`
`208`	`208`	`}`
`209`	`209`
`210`		`- span = mg.Single().Span;`
`211`		`- return true;`
	`210`	`+ span = default;`
	`211`	`+ return false;`
`212`	`212`	`}`
`213`	`213`
`214`	`214`	`/// <summary>`