tsai
/
ImageSharp
mirror of https://github.com/SixLabors/ImageSharp
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

Minor perf changes.

pull/643/head
James Jackson-South 8 years ago
parent
1a79cfb002
commit
f2e05bfcbc
1 changed files with 18 additions and 18 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 36
      src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/ScanDecoder.cs

36
src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/ScanDecoder.cs
View File

@ -22,6 +22,14 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
private readonly DoubleBufferedStreamReader stream;
private readonly PdfJsFrameComponent[] components;
private readonly ZigZag dctZigZag;
private readonly int restartInterval;
private readonly int componentIndex;
private readonly int componentsLength;
private readonly int spectralStart;
private readonly int spectralEnd;
private readonly int successiveHigh;
private readonly int successiveLow;
private int codeBits;
private uint codeBuffer;
private bool nomore;
@ -29,16 +37,8 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
private byte marker;
private bool badMarker;
private long markerPosition;
private int todo;
private int restartInterval;
private int componentIndex;
private int componentsLength;
private int eobrun;
private int spectralStart;
private int spectralEnd;
private int successiveHigh;
private int successiveLow;
/// <summary>
/// Initializes a new instance of the <see cref="ScanDecoder"/> class.
@ -126,7 +126,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
ref short blockDataRef = ref MemoryMarshal.GetReference(MemoryMarshal.Cast<Block8x8, short>(component.SpectralBlocks.Span));
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ReadOnlySpan<short> fastAC = fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId);
ref short fastACRef = ref MemoryMarshal.GetReference(fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId));
int mcu = 0;
for (int j = 0; j < h; j++)
@ -141,7 +141,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
int blockRow = mcu / w;
int blockCol = mcu % w;
int offset = component.GetBlockBufferOffset(blockRow, blockCol);
this.DecodeBlock(component, ref Unsafe.Add(ref blockDataRef, offset), ref dcHuffmanTable, ref acHuffmanTable, fastAC);
this.DecodeBlock(component, ref Unsafe.Add(ref blockDataRef, offset), ref dcHuffmanTable, ref acHuffmanTable, ref fastACRef);
mcu++;
// Every data block is an MCU, so countdown the restart interval
@ -181,7 +181,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
ref short blockDataRef = ref MemoryMarshal.GetReference(MemoryMarshal.Cast<Block8x8, short>(component.SpectralBlocks.Span));
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ReadOnlySpan<short> fastAC = fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId);
ref short fastACRef = ref MemoryMarshal.GetReference(fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId));
int h = component.HorizontalSamplingFactor;
int v = component.VerticalSamplingFactor;
@ -201,7 +201,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
int blockRow = (mcuRow * v) + y;
int blockCol = (mcuCol * h) + x;
int offset = component.GetBlockBufferOffset(blockRow, blockCol);
this.DecodeBlock(component, ref Unsafe.Add(ref blockDataRef, offset), ref dcHuffmanTable, ref acHuffmanTable, fastAC);
this.DecodeBlock(component, ref Unsafe.Add(ref blockDataRef, offset), ref dcHuffmanTable, ref acHuffmanTable, ref fastACRef);
}
}
}
@ -249,7 +249,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
ref short blockDataRef = ref MemoryMarshal.GetReference(MemoryMarshal.Cast<Block8x8, short>(component.SpectralBlocks.Span));
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ReadOnlySpan<short> fastAC = fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId);
ref short fastACRef = ref MemoryMarshal.GetReference(fastACTables.Tables.GetRowSpan(component.ACHuffmanTableId));
int mcu = 0;
for (int j = 0; j < h; j++)
@ -271,7 +271,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
}
else
{
this.DecodeBlockProgressiveAC(ref Unsafe.Add(ref blockDataRef, offset), ref acHuffmanTable, fastAC);
this.DecodeBlockProgressiveAC(ref Unsafe.Add(ref blockDataRef, offset), ref acHuffmanTable, ref fastACRef);
}
mcu++;
@ -367,7 +367,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
ref short blockDataRef,
ref PdfJsHuffmanTable dcTable,
ref PdfJsHuffmanTable acTable,
ReadOnlySpan<short> fastAc)
ref short fastACRef)
{
this.CheckBits();
int t = this.DecodeHuffman(ref dcTable);
@ -391,7 +391,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
this.CheckBits();
int c = this.PeekBits();
int r = fastAc[c];
int r = Unsafe.Add(ref fastACRef, c);
if (r != 0)
{
@ -474,7 +474,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
private void DecodeBlockProgressiveAC(
ref short blockDataRef,
ref PdfJsHuffmanTable acTable,
ReadOnlySpan<short> fastAc)
ref short fastACRef)
{
int k;
@ -501,7 +501,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
this.CheckBits();
int c = this.PeekBits();
int r = fastAc[c];
int r = Unsafe.Add(ref fastACRef, c);
if (r != 0)
{

Write Preview
Loading…
Cancel
Save