Optimize matrix read/write

src/ImageSharp/Metadata/Profiles/ICC/DataReader/IccDataReader.Matrix.cs

@@ -17,16 +17,23 @@ internal sealed partial class IccDataReader
     /// <returns>The read matrix</returns>
     public float[,] ReadMatrix(int xCount, int yCount, bool isSingle)
     {
-        var matrix = new float[xCount, yCount];
+        float[,] matrix = new float[xCount, yCount];
-        for (int y = 0; y < yCount; y++)
+
+        if (isSingle)
         {
-            for (int x = 0; x < xCount; x++)
+            for (int y = 0; y < yCount; y++)
             {
-                if (isSingle)
+                for (int x = 0; x < xCount; x++)
                 {
                     matrix[x, y] = this.ReadSingle();
                 }
-                else
+            }
+        }
+        else
+        {
+            for (int y = 0; y < yCount; y++)
+            {
+                for (int x = 0; x < xCount; x++)
                 {
                     matrix[x, y] = this.ReadFix16();
                 }
@@ -44,14 +51,17 @@ internal sealed partial class IccDataReader
     /// <returns>The read matrix</returns>
     public float[] ReadMatrix(int yCount, bool isSingle)
     {
-        var matrix = new float[yCount];
+        float[] matrix = new float[yCount];
-        for (int i = 0; i < yCount; i++)
+        if (isSingle)
         {
-            if (isSingle)
+            for (int i = 0; i < yCount; i++)
             {
                 matrix[i] = this.ReadSingle();
             }
-            else
+        }
+        else
+        {
+            for (int i = 0; i < yCount; i++)
             {
                 matrix[i] = this.ReadFix16();
             }

src/ImageSharp/Metadata/Profiles/ICC/DataWriter/IccDataWriter.Matrix.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Six Labors.
+// Copyright (c) Six Labors.
 // Licensed under the Six Labors Split License.
 
 using System.Numerics;
@@ -61,15 +61,21 @@ internal sealed partial class IccDataWriter
     public int WriteMatrix(in DenseMatrix<float> value, bool isSingle)
     {
         int count = 0;
-        for (int y = 0; y < value.Rows; y++)
+        if (isSingle)
         {
-            for (int x = 0; x < value.Columns; x++)
+            for (int y = 0; y < value.Rows; y++)
             {
-                if (isSingle)
+                for (int x = 0; x < value.Columns; x++)
                 {
                     count += this.WriteSingle(value[x, y]);
                 }
-                else
+            }
+        }
+        else
+        {
+            for (int y = 0; y < value.Rows; y++)
+            {
+                for (int x = 0; x < value.Columns; x++)
                 {
                     count += this.WriteFix16(value[x, y]);
                 }
@@ -88,15 +94,22 @@ internal sealed partial class IccDataWriter
     public int WriteMatrix(float[,] value, bool isSingle)
     {
         int count = 0;
-        for (int y = 0; y < value.GetLength(1); y++)
+
+        if (isSingle)
         {
-            for (int x = 0; x < value.GetLength(0); x++)
+            for (int y = 0; y < value.GetLength(1); y++)
             {
-                if (isSingle)
+                for (int x = 0; x < value.GetLength(0); x++)
                 {
                     count += this.WriteSingle(value[x, y]);
                 }
-                else
+            }
+        }
+        else
+        {
+            for (int y = 0; y < value.GetLength(1); y++)
+            {
+                for (int x = 0; x < value.GetLength(0); x++)
                 {
                     count += this.WriteFix16(value[x, y]);
                 }