Improve performance of Tiff decoders

SixLabors · Aug 22, 2019 · 1b32629 · 1b32629
1 parent e101736
commit 1b32629
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Showing 12 changed files with 47 additions and 16 deletions.
diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero1TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero1TiffColor.cs
@@ -33,17 +33,18 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
                 for (int x = left; x < left + width; x += 8)
                 {
                     byte b = data[offset++];
                     int maxShift = Math.Min(left + width - x, 8);
 
-                    for (int shift = 0; shift < maxShift; shift++)
+                    for (int shift = 0, index = x; shift < maxShift; shift++, index++)
                     {
                         int bit = (b >> (7 - shift)) & 1;
                         byte intensity = (bit == 1) ? (byte)255 : (byte)0;
                         color.FromRgba32(new Rgba32(intensity, intensity, intensity, 255));
-                        pixels[x + shift, y] = color;
+                        buffer[index] = color;
                     }
                 }
             }

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero4TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero4TiffColor.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -33,17 +34,19 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width - 1; x += 2)
                 {
                     byte byteData = data[offset++];
 
                     byte intensity1 = (byte)(((byteData & 0xF0) >> 4) * 17);
                     color.FromRgba32(new Rgba32(intensity1, intensity1, intensity1, 255));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
 
                     byte intensity2 = (byte)((byteData & 0x0F) * 17);
                     color.FromRgba32(new Rgba32(intensity2, intensity2, intensity2, 255));
-                    pixels[x + 1, y] = color;
+                    buffer[x + 1] = color;
                 }
 
                 if (isOddWidth)

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero8TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZero8TiffColor.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -32,11 +33,13 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     byte intensity = data[offset++];
                     color.FromRgba32(new Rgba32(intensity, intensity, intensity, 255));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
                 }
             }
         }

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZeroTiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/BlackIsZeroTiffColor.cs
@@ -36,12 +36,14 @@ public static void Decode<TPixel>(byte[] data, uint[] bitsPerSample, Buffer2D<TP
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     int value = bitReader.ReadBits(bitsPerSample[0]);
                     float intensity = ((float)value) / factor;
                     color.FromVector4(new Vector4(intensity, intensity, intensity, 1.0f));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
                 }
 
                 bitReader.NextRow();

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/PaletteTiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/PaletteTiffColor.cs
@@ -37,10 +37,12 @@ public static void Decode<TPixel>(byte[] data, uint[] bitsPerSample, uint[] colo
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     int index = bitReader.ReadBits(bitsPerSample[0]);
-                    pixels[x, y] = palette[index];
+                    buffer[x] = palette[index];
                 }
 
                 bitReader.NextRow();

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/Rgb888TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/Rgb888TiffColor.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -32,13 +33,15 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     byte r = data[offset++];
                     byte g = data[offset++];
                     byte b = data[offset++];
                     color.FromRgba32(new Rgba32(r, g, b, 255));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
                 }
             }
         }

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/RgbPlanarTiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/RgbPlanarTiffColor.cs
@@ -40,13 +40,16 @@ public static void Decode<TPixel>(byte[][] data, uint[] bitsPerSample, Buffer2D<
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     float r = ((float)rBitReader.ReadBits(bitsPerSample[0])) / rFactor;
                     float g = ((float)gBitReader.ReadBits(bitsPerSample[1])) / gFactor;
                     float b = ((float)bBitReader.ReadBits(bitsPerSample[2])) / bFactor;
                     color.FromVector4(new Vector4(r, g, b, 1.0f));
-                    pixels[x, y] = color;
+
+                    buffer[x] = color;
                 }
 
                 rBitReader.NextRow();

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/RgbTiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/RgbTiffColor.cs
@@ -38,13 +38,16 @@ public static void Decode<TPixel>(byte[] data, uint[] bitsPerSample, Buffer2D<TP
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     float r = ((float)bitReader.ReadBits(bitsPerSample[0])) / rFactor;
                     float g = ((float)bitReader.ReadBits(bitsPerSample[1])) / gFactor;
                     float b = ((float)bitReader.ReadBits(bitsPerSample[2])) / bFactor;
                     color.FromVector4(new Vector4(r, g, b, 1.0f));
-                    pixels[x, y] = color;
+
+                    buffer[x] = color;
                 }
 
                 bitReader.NextRow();

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero1TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero1TiffColor.cs
@@ -33,17 +33,20 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x += 8)
                 {
                     byte b = data[offset++];
                     int maxShift = Math.Min(left + width - x, 8);
 
-                    for (int shift = 0; shift < maxShift; shift++)
+                    for (int shift = 0, index = x; shift < maxShift; shift++, index++)
                     {
                         int bit = (b >> (7 - shift)) & 1;
                         byte intensity = (bit == 1) ? (byte)0 : (byte)255;
                         color.FromRgba32(new Rgba32(intensity, intensity, intensity, 255));
-                        pixels[x + shift, y] = color;
+
+                        buffer[index] = color;
                     }
                 }
             }

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero4TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero4TiffColor.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -33,17 +34,19 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width - 1; x += 2)
                 {
                     byte byteData = data[offset++];
 
                     byte intensity1 = (byte)((15 - ((byteData & 0xF0) >> 4)) * 17);
                     color.FromRgba32(new Rgba32(intensity1, intensity1, intensity1, 255));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
 
                     byte intensity2 = (byte)((15 - (byteData & 0x0F)) * 17);
                     color.FromRgba32(new Rgba32(intensity2, intensity2, intensity2, 255));
-                    pixels[x + 1, y] = color;
+                    buffer[x + 1] = color;
                 }
 
                 if (isOddWidth)

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero8TiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZero8TiffColor.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Runtime.CompilerServices;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
@@ -32,11 +33,13 @@ public static void Decode<TPixel>(byte[] data, Buffer2D<TPixel> pixels, int left
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     byte intensity = (byte)(255 - data[offset++]);
                     color.FromRgba32(new Rgba32(intensity, intensity, intensity, 255));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
                 }
             }
         }

diff --git a/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZeroTiffColor.cs b/src/ImageSharp/Formats/Tiff/PhotometricInterpretation/WhiteIsZeroTiffColor.cs
@@ -36,12 +36,14 @@ public static void Decode<TPixel>(byte[] data, uint[] bitsPerSample, Buffer2D<TP
 
             for (int y = top; y < top + height; y++)
             {
+                Span<TPixel> buffer = pixels.GetRowSpan(y);
+
                 for (int x = left; x < left + width; x++)
                 {
                     int value = bitReader.ReadBits(bitsPerSample[0]);
                     float intensity = 1.0f - (((float)value) / factor);
                     color.FromVector4(new Vector4(intensity, intensity, intensity, 1.0f));
-                    pixels[x, y] = color;
+                    buffer[x] = color;
                 }
 
                 bitReader.NextRow();