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ScanDecoder: refactor parameters to members

af/merge-core
Anton Firszov 8 years ago
parent
27269683b9
commit
f790a8cc82
3 changed files with 61 additions and 63 deletions
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  1. 9
      src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/FastACTables.cs
  2. 108
      src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/ScanDecoder.cs
  3. 7
      src/ImageSharp/Formats/Jpeg/PdfJsPort/PdfJsJpegDecoderCore.cs

9
src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/FastACTables.cs
View File

@ -34,6 +34,15 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
return this.tables.GetRowSpan(index);
}
/// <summary>
/// Gets a reference to the first element of the AC table indexed by <see cref="PdfJsFrameComponent.ACHuffmanTableId"/>
/// </summary>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public ref short GetAcTableReference(PdfJsFrameComponent component)
{
return ref this.tables.GetRowSpan(component.ACHuffmanTableId)[0];
}
/// <summary>
/// Builds a lookup table for fast AC entropy scan decoding.
/// </summary>

108
src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/ScanDecoder.cs
View File

@ -23,6 +23,11 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
// LUT Bias[n] = (-1 << n) + 1
private static readonly int[] Bias = { 0, -1, -3, -7, -15, -31, -63, -127, -255, -511, -1023, -2047, -4095, -8191, -16383, -32767 };
private readonly PdfJsFrame frame;
private readonly PdfJsHuffmanTables dcHuffmanTables;
private readonly PdfJsHuffmanTables acHuffmanTables;
private readonly FastACTables fastACTables;
private readonly DoubleBufferedStreamReader stream;
private readonly PdfJsFrameComponent[] components;
private readonly ZigZag dctZigZag;
@ -79,7 +84,10 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
/// Initializes a new instance of the <see cref="ScanDecoder"/> class.
/// </summary>
/// <param name="stream">The input stream.</param>
/// <param name="components">The scan components.</param>
/// <param name="frame">The image frame.</param>
/// <param name="dcHuffmanTables">The DC Huffman tables.</param>
/// <param name="acHuffmanTables">The AC Huffman tables.</param>
/// <param name="fastACTables">The fast AC decoding tables.</param>
/// <param name="componentIndex">The component index within the array.</param>
/// <param name="componentsLength">The length of the components. Different to the array length.</param>
/// <param name="restartInterval">The reset interval.</param>
@ -89,7 +97,10 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
/// <param name="successiveLow">The successive approximation bit low end.</param>
public ScanDecoder(
DoubleBufferedStreamReader stream,
PdfJsFrameComponent[] components,
PdfJsFrame frame,
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables,
int componentIndex,
int componentsLength,
int restartInterval,
@ -100,7 +111,11 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
{
this.dctZigZag = ZigZag.CreateUnzigTable();
this.stream = stream;
this.components = components;
this.frame = frame;
this.dcHuffmanTables = dcHuffmanTables;
this.acHuffmanTables = acHuffmanTables;
this.fastACTables = fastACTables;
this.components = frame.Components;
this.marker = JpegConstants.Markers.XFF;
this.markerPosition = 0;
this.componentIndex = componentIndex;
@ -115,25 +130,17 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
/// <summary>
/// Decodes the entropy coded data.
/// </summary>
/// <param name="frame">The image frame.</param>
/// <param name="dcHuffmanTables">The DC Huffman tables.</param>
/// <param name="acHuffmanTables">The AC Huffman tables.</param>
/// <param name="fastACTables">The fast AC decoding tables.</param>
public void ParseEntropyCodedData(
PdfJsFrame frame,
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
public void ParseEntropyCodedData()
{
this.Reset();
if (!frame.Progressive)
if (!this.frame.Progressive)
{
this.ParseBaselineData(frame, dcHuffmanTables, acHuffmanTables, fastACTables);
this.ParseBaselineData();
}
else
{
this.ParseProgressiveData(frame, dcHuffmanTables, acHuffmanTables, fastACTables);
this.ParseProgressiveData();
}
if (this.badMarker)
@ -145,32 +152,24 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static uint LRot(uint x, int y) => (x << y) | (x >> (32 - y));
private void ParseBaselineData(
PdfJsFrame frame,
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
private void ParseBaselineData()
{
if (this.componentsLength == 1)
{
this.ParseBaselineDataNonInterleaved(dcHuffmanTables, acHuffmanTables, fastACTables);
this.ParseBaselineDataNonInterleaved();
}
else
{
this.ParseBaselineDataInterleaved(frame, dcHuffmanTables, acHuffmanTables, fastACTables);
this.ParseBaselineDataInterleaved();
}
}
private void ParseBaselineDataInterleaved(
PdfJsFrame frame,
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
private void ParseBaselineDataInterleaved()
{
// Interleaved
int mcu = 0;
int mcusPerColumn = frame.McusPerColumn;
int mcusPerLine = frame.McusPerLine;
int mcusPerColumn = this.frame.McusPerColumn;
int mcusPerLine = this.frame.McusPerLine;
for (int j = 0; j < mcusPerColumn; j++)
{
for (int i = 0; i < mcusPerLine; i++)
@ -180,10 +179,9 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
{
PdfJsFrameComponent component = this.components[k];
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef =
ref MemoryMarshal.GetReference(fastACTables.GetTableSpan(component.ACHuffmanTableId));
ref PdfJsHuffmanTable dcHuffmanTable = ref this.dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref this.acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef = ref this.fastACTables.GetAcTableReference(component);
int h = component.HorizontalSamplingFactor;
int v = component.VerticalSamplingFactor;
@ -231,19 +229,16 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
/// number of blocks to do just depends on how many actual "pixels"
/// component has, independent of interleaved MCU blocking and such
/// </summary>
private void ParseBaselineDataNonInterleaved(
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
private void ParseBaselineDataNonInterleaved()
{
PdfJsFrameComponent component = this.components[this.componentIndex];
int w = component.WidthInBlocks;
int h = component.HeightInBlocks;
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef = ref MemoryMarshal.GetReference(fastACTables.GetTableSpan(component.ACHuffmanTableId));
ref PdfJsHuffmanTable dcHuffmanTable = ref this.dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref this.acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef = ref this.fastACTables.GetAcTableReference(component);
int mcu = 0;
for (int j = 0; j < h; j++)
@ -276,28 +271,24 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
}
}
private void ParseProgressiveData(
PdfJsFrame frame,
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
private void ParseProgressiveData()
{
if (this.componentsLength == 1)
{
this.ParseProgressiveDataNonInterleaved(dcHuffmanTables, acHuffmanTables, fastACTables);
this.ParseProgressiveDataNonInterleaved();
}
else
{
this.ParseProgressiveDataInterleaved(frame, dcHuffmanTables);
this.ParseProgressiveDataInterleaved();
}
}
private void ParseProgressiveDataInterleaved(PdfJsFrame frame, PdfJsHuffmanTables dcHuffmanTables)
private void ParseProgressiveDataInterleaved()
{
// Interleaved
int mcu = 0;
int mcusPerColumn = frame.McusPerColumn;
int mcusPerLine = frame.McusPerLine;
int mcusPerColumn = this.frame.McusPerColumn;
int mcusPerLine = this.frame.McusPerLine;
for (int j = 0; j < mcusPerColumn; j++)
{
for (int i = 0; i < mcusPerLine; i++)
@ -306,9 +297,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
for (int k = 0; k < this.componentsLength; k++)
{
PdfJsFrameComponent component = this.components[k];
ref short blockDataRef = ref MemoryMarshal.GetReference(
MemoryMarshal.Cast<Block8x8, short>(component.SpectralBlocks.Span));
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable dcHuffmanTable = ref this.dcHuffmanTables[component.DCHuffmanTableId];
int h = component.HorizontalSamplingFactor;
int v = component.VerticalSamplingFactor;
@ -327,7 +316,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
int mcuCol = mcu % mcusPerLine;
int blockRow = (mcuRow * v) + y;
int blockCol = (mcuCol * h) + x;
int offset = component.GetBlockBufferOffset(blockRow, blockCol);
this.DecodeBlockProgressiveDC(
component,
blockRow,
@ -354,19 +343,16 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
/// number of blocks to do just depends on how many actual "pixels" this
/// component has, independent of interleaved MCU blocking and such
/// </summary>
private void ParseProgressiveDataNonInterleaved(
PdfJsHuffmanTables dcHuffmanTables,
PdfJsHuffmanTables acHuffmanTables,
FastACTables fastACTables)
private void ParseProgressiveDataNonInterleaved()
{
PdfJsFrameComponent component = this.components[this.componentIndex];
int w = component.WidthInBlocks;
int h = component.HeightInBlocks;
ref PdfJsHuffmanTable dcHuffmanTable = ref dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef = ref MemoryMarshal.GetReference(fastACTables.GetTableSpan(component.ACHuffmanTableId));
ref PdfJsHuffmanTable dcHuffmanTable = ref this.dcHuffmanTables[component.DCHuffmanTableId];
ref PdfJsHuffmanTable acHuffmanTable = ref this.acHuffmanTables[component.ACHuffmanTableId];
ref short fastACRef = ref this.fastACTables.GetAcTableReference(component);
int mcu = 0;
for (int j = 0; j < h; j++)

7
src/ImageSharp/Formats/Jpeg/PdfJsPort/PdfJsJpegDecoderCore.cs
View File

@ -806,7 +806,10 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort
var sd = new ScanDecoder(
this.InputStream,
this.Frame.Components,
this.Frame,
this.dcHuffmanTables,
this.acHuffmanTables,
this.fastACTables,
componentIndex,
selectorsCount,
this.resetInterval,
@ -815,7 +818,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort
successiveApproximation >> 4,
successiveApproximation & 15);
sd.ParseEntropyCodedData(this.Frame, this.dcHuffmanTables, this.acHuffmanTables, this.fastACTables);
sd.ParseEntropyCodedData();
}
/// <summary>

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