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started work on DecoderScanProcessor

af/merge-core
antonfirsov 9 years ago
parent
327d505e21
commit
38d6e3277a
5 changed files with 397 additions and 153 deletions
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  1. 1
      ImageSharp.sln.DotSettings
  2. 229
      src/ImageSharp/Formats/Jpg/Components/Decoder/DecoderScanProcessor.cs
  3. 6
      src/ImageSharp/Formats/Jpg/Components/Decoder/HuffmanTree.cs
  4. 26
      src/ImageSharp/Formats/Jpg/Components/Decoder/Scan.cs
  5. 288
      src/ImageSharp/Formats/Jpg/JpegDecoderCore.cs

1
ImageSharp.sln.DotSettings
View File

@ -345,6 +345,7 @@
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=FDCT/@EntryIndexedValue">FDCT</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=IDCT/@EntryIndexedValue">IDCT</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=JPEG/@EntryIndexedValue">JPEG</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=MCU/@EntryIndexedValue">MCU</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=PNG/@EntryIndexedValue">PNG</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=RGB/@EntryIndexedValue">RGB</s:String>
<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/Abbreviations/=RLE/@EntryIndexedValue">RLE</s:String>

229
src/ImageSharp/Formats/Jpg/Components/Decoder/DecoderScanProcessor.cs
View File

@ -0,0 +1,229 @@
namespace ImageSharp.Formats.Jpg
{
using System;
internal unsafe struct DecoderScanProcessor
{
public struct ComponentData
{
public Block8x8F Block;
public Block8x8F Temp1;
public Block8x8F Temp2;
public UnzigData Unzig;
public fixed byte ScanData [3 * JpegDecoderCore.MaxComponents];
public fixed int Dc [JpegDecoderCore.MaxComponents];
public static ComponentData Create()
{
ComponentData data = default(ComponentData);
data.Unzig = UnzigData.Create();
return data;
}
}
public struct ComponentPointers
{
public Block8x8F* Block;
public Block8x8F* Temp1;
public Block8x8F* Temp2;
public int* Unzig;
public Scan* Scan;
public int* Dc;
public ComponentPointers(ComponentData* basePtr)
{
this.Block = &basePtr->Block;
this.Temp1 = &basePtr->Temp1;
this.Temp2 = &basePtr->Temp2;
this.Unzig = basePtr->Unzig.Data;
this.Scan = (Scan*) basePtr->ScanData;
this.Dc = basePtr->Dc;
}
}
public int bx;
public int by;
public int zigStart;
public int zigEnd;
public int ah;
public int al;
public int mxx;
public int myy;
public ComponentData Data;
public ComponentPointers Pointers;
public static void Init(DecoderScanProcessor* p, JpegDecoderCore decoder, int remaining)
{
p->Pointers = new ComponentPointers(&p->Data);
}
private void InitCommon(JpegDecoderCore decoder, int remaining)
{
if (decoder.ComponentCount == 0)
{
throw new ImageFormatException("Missing SOF marker");
}
if (remaining < 6 || 4 + (2 * decoder.ComponentCount) < remaining || remaining % 2 != 0)
{
throw new ImageFormatException("SOS has wrong length");
}
decoder.ReadFull(decoder.Temp, 0, remaining);
byte scanComponentCount = decoder.Temp[0];
int scanComponentCountX2 = 2 * scanComponentCount;
if (remaining != 4 + scanComponentCountX2)
{
throw new ImageFormatException("SOS length inconsistent with number of components");
}
int totalHv = 0;
for (int i = 0; i < scanComponentCount; i++)
{
this.ProcessScanImpl(decoder, i, ref this.Pointers.Scan[i], ref totalHv);
}
// Section B.2.3 states that if there is more than one component then the
// total H*V values in a scan must be <= 10.
if (decoder.ComponentCount > 1 && totalHv > 10)
{
throw new ImageFormatException("Total sampling factors too large.");
}
this.zigEnd = Block8x8F.ScalarCount - 1;
if (decoder.IsProgressive)
{
this.zigStart = decoder.Temp[1 + scanComponentCountX2];
this.zigEnd = decoder.Temp[2 + scanComponentCountX2];
this.ah = decoder.Temp[3 + scanComponentCountX2] >> 4;
this.al = decoder.Temp[3 + scanComponentCountX2] & 0x0f;
if ((this.zigStart == 0 && this.zigEnd != 0) || this.zigStart > this.zigEnd
|| this.zigEnd >= Block8x8F.ScalarCount)
{
throw new ImageFormatException("Bad spectral selection bounds");
}
if (this.zigStart != 0 && scanComponentCount != 1)
{
throw new ImageFormatException("Progressive AC coefficients for more than one component");
}
if (this.ah != 0 && this.ah != this.al + 1)
{
throw new ImageFormatException("Bad successive approximation values");
}
}
// mxx and myy are the number of MCUs (Minimum Coded Units) in the image.
int h0 = decoder.ComponentArray[0].HorizontalFactor;
int v0 = decoder.ComponentArray[0].VerticalFactor;
this.mxx = (decoder.ImageWidth + (8 * h0) - 1) / (8 * h0);
this.myy = (decoder.ImageHeight + (8 * v0) - 1) / (8 * v0);
if (decoder.IsProgressive)
{
for (int i = 0; i < scanComponentCount; i++)
{
int compIndex = this.Pointers.Scan[i].Index;
if (decoder.ProgCoeffs[compIndex] == null)
{
int size = mxx * myy * decoder.ComponentArray[compIndex].HorizontalFactor
* decoder.ComponentArray[compIndex].VerticalFactor;
decoder.ProgCoeffs[compIndex] = new Block8x8F[size];
}
}
}
}
private void ProcessScanImpl(JpegDecoderCore decoder, int i, ref Scan currentScan, ref int totalHv)
{
// Component selector.
int cs = decoder.Temp[1 + (2 * i)];
int compIndex = -1;
for (int j = 0; j < decoder.ComponentCount; j++)
{
// Component compv = ;
if (cs == decoder.ComponentArray[j].Identifier)
{
compIndex = j;
}
}
if (compIndex < 0)
{
throw new ImageFormatException("Unknown component selector");
}
currentScan.Index = (byte)compIndex;
this.ProcessComponentImpl(decoder, i, ref currentScan, ref totalHv, ref decoder.ComponentArray[compIndex]);
}
private void ProcessComponentImpl(
JpegDecoderCore decoder,
int i,
ref Scan currentScan,
ref int totalHv,
ref Component currentComponent)
{
// Section B.2.3 states that "the value of Cs_j shall be different from
// the values of Cs_1 through Cs_(j-1)". Since we have previously
// verified that a frame's component identifiers (C_i values in section
// B.2.2) are unique, it suffices to check that the implicit indexes
// into comp are unique.
for (int j = 0; j < i; j++)
{
if (currentScan.Index == this.Pointers.Scan[j].Index)
{
throw new ImageFormatException("Repeated component selector");
}
}
totalHv += currentComponent.HorizontalFactor * currentComponent.VerticalFactor;
currentScan.DcTableSelector = (byte)(decoder.Temp[2 + (2 * i)] >> 4);
if (currentScan.DcTableSelector > HuffmanTree.MaxTh)
{
throw new ImageFormatException("Bad DC table selector value");
}
currentScan.AcTableSelector = (byte)(decoder.Temp[2 + (2 * i)] & 0x0f);
if (currentScan.AcTableSelector > HuffmanTree.MaxTh)
{
throw new ImageFormatException("Bad AC table selector value");
}
}
private void InitProgressive(JpegDecoderCore decoder)
{
}
}
}

6
src/ImageSharp/Formats/Jpg/Components/Decoder/HuffmanTree.cs
View File

@ -91,7 +91,7 @@ namespace ImageSharp.Formats.Jpg
/// <summary>
/// Creates and initializes an array of <see cref="HuffmanTree" /> instances of size <see cref="NumberOfTrees" />
/// </summary>
/// <returns>An array of <see cref="HuffmanTree" /> instances representing the Huffman table</returns>
/// <returns>An array of <see cref="HuffmanTree" /> instances representing the Huffman tables</returns>
public static HuffmanTree[] CreateHuffmanTrees()
{
HuffmanTree[] result = new HuffmanTree[NumberOfTrees];
@ -109,7 +109,7 @@ namespace ImageSharp.Formats.Jpg
/// <summary>
/// Initializes the Huffman tree
/// </summary>
public void Init()
private void Init()
{
this.Lut = UshortBuffer.Rent(1 << LutSize);
this.Values = ByteBuffer.Rent(MaxNCodes);
@ -134,7 +134,7 @@ namespace ImageSharp.Formats.Jpg
/// Internal part of the DHT processor, whatever does it mean
/// </summary>
/// <param name="decoder">The decoder instance</param>
/// <param name="defineHuffmanTablesData">The temporal buffer that holds the data that has been read from stream</param>
/// <param name="defineHuffmanTablesData">The temporal buffer that holds the data that has been read from the Jpeg stream</param>
/// <param name="remaining">Remaining bits</param>
internal void ProcessDefineHuffmanTablesMarkerLoop(
JpegDecoderCore decoder,

26
src/ImageSharp/Formats/Jpg/Components/Decoder/Scan.cs
View File

@ -0,0 +1,26 @@
namespace ImageSharp.Formats.Jpg
{
using System.Runtime.InteropServices;
/// <summary>
/// Represents a component scan
/// </summary>
[StructLayout(LayoutKind.Sequential)]
internal struct Scan
{
/// <summary>
/// Gets or sets the component index.
/// </summary>
public byte Index;
/// <summary>
/// Gets or sets the DC table selector
/// </summary>
public byte DcTableSelector;
/// <summary>
/// Gets or sets the AC table selector
/// </summary>
public byte AcTableSelector;
}
}

288
src/ImageSharp/Formats/Jpg/JpegDecoderCore.cs
View File

@ -10,7 +10,7 @@ namespace ImageSharp.Formats
using System.Threading.Tasks;
using ImageSharp.Formats.Jpg;
/// <summary>
/// Performs the jpeg decoding operation.
/// </summary>
@ -29,7 +29,7 @@ namespace ImageSharp.Formats
/// <summary>
/// The maximum number of color components
/// </summary>
private const int MaxComponents = 4;
internal const int MaxComponents = 4;
/// <summary>
/// The maximum number of quantization tables
@ -39,7 +39,7 @@ namespace ImageSharp.Formats
/// <summary>
/// The component array
/// </summary>
private readonly Component[] componentArray;
internal Component[] ComponentArray { get; }
/// <summary>
/// The huffman trees
@ -49,17 +49,17 @@ namespace ImageSharp.Formats
/// <summary>
/// Saved state between progressive-mode scans.
/// </summary>
private readonly Block8x8F[][] progCoeffs;
internal Block8x8F[][] ProgCoeffs { get; }
/// <summary>
/// Quantization tables, in zigzag order.
/// </summary>
private readonly Block8x8F[] quantizationTables;
internal Block8x8F[] QuantizationTables { get; }
/// <summary>
/// A temporary buffer for holding pixels
/// </summary>
private readonly byte[] temp;
internal byte[] Temp { get; }
// TODO: the usage of this buffer is unclean + need to move it to the stack for performance
@ -90,7 +90,7 @@ namespace ImageSharp.Formats
/// <summary>
/// The number of color components within the image.
/// </summary>
private int componentCount;
internal int ComponentCount { get; private set; }
/// <summary>
/// End-of-Band run, specified in section G.1.2.2.
@ -110,12 +110,12 @@ namespace ImageSharp.Formats
/// <summary>
/// The image height
/// </summary>
private int imageHeight;
internal int ImageHeight { get; private set; }
/// <summary>
/// The image width
/// </summary>
private int imageWidth;
internal int ImageWidth { get; private set; }
/// <summary>
/// The byte buffer.
@ -130,7 +130,7 @@ namespace ImageSharp.Formats
/// <summary>
/// Whether the image is interlaced (progressive)
/// </summary>
private bool isProgressive;
public bool IsProgressive { get; private set; }
/// <summary>
/// The restart interval
@ -153,10 +153,10 @@ namespace ImageSharp.Formats
public JpegDecoderCore()
{
this.huffmanTrees = HuffmanTree.CreateHuffmanTrees();
this.quantizationTables = new Block8x8F[MaxTq + 1];
this.temp = new byte[2 * Block8x8F.ScalarCount];
this.componentArray = new Component[MaxComponents];
this.progCoeffs = new Block8x8F[MaxComponents][];
this.QuantizationTables = new Block8x8F[MaxTq + 1];
this.Temp = new byte[2 * Block8x8F.ScalarCount];
this.ComponentArray = new Component[MaxComponents];
this.ProgCoeffs = new Block8x8F[MaxComponents][];
this.bits = default(Bits);
this.bytes = Bytes.Create();
}
@ -219,8 +219,8 @@ namespace ImageSharp.Formats
this.inputStream = stream;
// Check for the Start Of Image marker.
this.ReadFull(this.temp, 0, 2);
if (this.temp[0] != JpegConstants.Markers.XFF || this.temp[1] != JpegConstants.Markers.SOI)
this.ReadFull(this.Temp, 0, 2);
if (this.Temp[0] != JpegConstants.Markers.XFF || this.Temp[1] != JpegConstants.Markers.SOI)
{
throw new ImageFormatException("Missing SOI marker.");
}
@ -228,8 +228,8 @@ namespace ImageSharp.Formats
// Process the remaining segments until the End Of Image marker.
while (true)
{
this.ReadFull(this.temp, 0, 2);
while (this.temp[0] != 0xff)
this.ReadFull(this.Temp, 0, 2);
while (this.Temp[0] != 0xff)
{
// Strictly speaking, this is a format error. However, libjpeg is
// liberal in what it accepts. As of version 9, next_marker in
@ -248,11 +248,11 @@ namespace ImageSharp.Formats
// mechanism within a scan (the RST[0-7] markers).
// Note that extraneous 0xff bytes in e.g. SOS data are escaped as
// "\xff\x00", and so are detected a little further down below.
this.temp[0] = this.temp[1];
this.temp[1] = this.ReadByte();
this.Temp[0] = this.Temp[1];
this.Temp[1] = this.ReadByte();
}
byte marker = this.temp[1];
byte marker = this.Temp[1];
if (marker == 0)
{
// Treat "\xff\x00" as extraneous data.
@ -285,8 +285,8 @@ namespace ImageSharp.Formats
// Read the 16-bit length of the segment. The value includes the 2 bytes for the
// length itself, so we subtract 2 to get the number of remaining bytes.
this.ReadFull(this.temp, 0, 2);
int remaining = (this.temp[0] << 8) + this.temp[1] - 2;
this.ReadFull(this.Temp, 0, 2);
int remaining = (this.Temp[0] << 8) + this.Temp[1] - 2;
if (remaining < 0)
{
throw new ImageFormatException("Short segment length.");
@ -297,7 +297,7 @@ namespace ImageSharp.Formats
case JpegConstants.Markers.SOF0:
case JpegConstants.Markers.SOF1:
case JpegConstants.Markers.SOF2:
this.isProgressive = marker == JpegConstants.Markers.SOF2;
this.IsProgressive = marker == JpegConstants.Markers.SOF2;
this.ProcessStartOfFrameMarker(remaining);
if (configOnly && this.isJfif)
{
@ -377,11 +377,11 @@ namespace ImageSharp.Formats
if (this.grayImage.IsInitialized)
{
this.ConvertFromGrayScale(this.imageWidth, this.imageHeight, image);
this.ConvertFromGrayScale(this.ImageWidth, this.ImageHeight, image);
}
else if (this.ycbcrImage != null)
{
if (this.componentCount == 4)
if (this.ComponentCount == 4)
{
if (!this.adobeTransformValid)
{
@ -394,26 +394,26 @@ namespace ImageSharp.Formats
// TODO: YCbCrA?
if (this.adobeTransform == JpegConstants.Adobe.ColorTransformYcck)
{
this.ConvertFromYcck(this.imageWidth, this.imageHeight, image);
this.ConvertFromYcck(this.ImageWidth, this.ImageHeight, image);
}
else if (this.adobeTransform == JpegConstants.Adobe.ColorTransformUnknown)
{
// Assume CMYK
this.ConvertFromCmyk(this.imageWidth, this.imageHeight, image);
this.ConvertFromCmyk(this.ImageWidth, this.ImageHeight, image);
}
return;
}
if (this.componentCount == 3)
if (this.ComponentCount == 3)
{
if (this.IsRGB())
{
this.ConvertFromRGB(this.imageWidth, this.imageHeight, image);
this.ConvertFromRGB(this.ImageWidth, this.ImageHeight, image);
return;
}
this.ConvertFromYCbCr(this.imageWidth, this.imageHeight, image);
this.ConvertFromYCbCr(this.ImageWidth, this.ImageHeight, image);
return;
}
@ -538,7 +538,7 @@ namespace ImageSharp.Formats
private void ConvertFromCmyk<TColor>(int width, int height, Image<TColor> image)
where TColor : struct, IPackedPixel, IEquatable<TColor>
{
int scale = this.componentArray[0].HorizontalFactor / this.componentArray[1].HorizontalFactor;
int scale = this.ComponentArray[0].HorizontalFactor / this.ComponentArray[1].HorizontalFactor;
image.InitPixels(width, height);
@ -613,7 +613,7 @@ namespace ImageSharp.Formats
private void ConvertFromRGB<TColor>(int width, int height, Image<TColor> image)
where TColor : struct, IPackedPixel, IEquatable<TColor>
{
int scale = this.componentArray[0].HorizontalFactor / this.componentArray[1].HorizontalFactor;
int scale = this.ComponentArray[0].HorizontalFactor / this.ComponentArray[1].HorizontalFactor;
image.InitPixels(width, height);
using (PixelAccessor<TColor> pixels = image.Lock())
@ -653,7 +653,7 @@ namespace ImageSharp.Formats
private void ConvertFromYCbCr<TColor>(int width, int height, Image<TColor> image)
where TColor : struct, IPackedPixel, IEquatable<TColor>
{
int scale = this.componentArray[0].HorizontalFactor / this.componentArray[1].HorizontalFactor;
int scale = this.ComponentArray[0].HorizontalFactor / this.ComponentArray[1].HorizontalFactor;
image.InitPixels(width, height);
using (PixelAccessor<TColor> pixels = image.Lock())
@ -693,7 +693,7 @@ namespace ImageSharp.Formats
private void ConvertFromYcck<TColor>(int width, int height, Image<TColor> image)
where TColor : struct, IPackedPixel, IEquatable<TColor>
{
int scale = this.componentArray[0].HorizontalFactor / this.componentArray[1].HorizontalFactor;
int scale = this.ComponentArray[0].HorizontalFactor / this.ComponentArray[1].HorizontalFactor;
image.InitPixels(width, height);
@ -836,7 +836,7 @@ namespace ImageSharp.Formats
private JpegPixelArea GetDestinationChannel(int compIndex)
{
if (this.componentCount == 1)
if (this.ComponentCount == 1)
{
return this.grayImage;
}
@ -878,8 +878,8 @@ namespace ImageSharp.Formats
return true;
}
return this.componentArray[0].Identifier == 'R' && this.componentArray[1].Identifier == 'G'
&& this.componentArray[2].Identifier == 'B';
return this.ComponentArray[0].Identifier == 'R' && this.ComponentArray[1].Identifier == 'G'
&& this.ComponentArray[2].Identifier == 'B';
}
/// <summary>
@ -894,16 +894,16 @@ namespace ImageSharp.Formats
return;
}
if (this.componentCount == 1)
if (this.ComponentCount == 1)
{
this.grayImage = JpegPixelArea.CreatePooled(8 * mxx, 8 * myy);
}
else
{
int h0 = this.componentArray[0].HorizontalFactor;
int v0 = this.componentArray[0].VerticalFactor;
int horizontalRatio = h0 / this.componentArray[1].HorizontalFactor;
int verticalRatio = v0 / this.componentArray[1].VerticalFactor;
int h0 = this.ComponentArray[0].HorizontalFactor;
int v0 = this.ComponentArray[0].VerticalFactor;
int horizontalRatio = h0 / this.ComponentArray[1].HorizontalFactor;
int verticalRatio = v0 / this.ComponentArray[1].VerticalFactor;
YCbCrImage.YCbCrSubsampleRatio ratio = YCbCrImage.YCbCrSubsampleRatio.YCbCrSubsampleRatio444;
switch ((horizontalRatio << 4) | verticalRatio)
@ -930,10 +930,10 @@ namespace ImageSharp.Formats
this.ycbcrImage = new YCbCrImage(8 * h0 * mxx, 8 * v0 * myy, ratio);
if (this.componentCount == 4)
if (this.ComponentCount == 4)
{
int h3 = this.componentArray[3].HorizontalFactor;
int v3 = this.componentArray[3].VerticalFactor;
int h3 = this.ComponentArray[3].HorizontalFactor;
int v3 = this.ComponentArray[3].VerticalFactor;
this.blackImage = JpegPixelArea.CreatePooled(8 * h3 * mxx, 8 * v3 * myy);
}
@ -1017,14 +1017,14 @@ namespace ImageSharp.Formats
return;
}
this.ReadFull(this.temp, 0, 12);
this.ReadFull(this.Temp, 0, 12);
remaining -= 12;
if (this.temp[0] == 'A' && this.temp[1] == 'd' && this.temp[2] == 'o' && this.temp[3] == 'b'
&& this.temp[4] == 'e')
if (this.Temp[0] == 'A' && this.Temp[1] == 'd' && this.Temp[2] == 'o' && this.Temp[3] == 'b'
&& this.Temp[4] == 'e')
{
this.adobeTransformValid = true;
this.adobeTransform = this.temp[11];
this.adobeTransform = this.Temp[11];
}
if (remaining > 0)
@ -1070,17 +1070,17 @@ namespace ImageSharp.Formats
return;
}
this.ReadFull(this.temp, 0, 13);
this.ReadFull(this.Temp, 0, 13);
remaining -= 13;
// TODO: We should be using constants for this.
this.isJfif = this.temp[0] == 'J' && this.temp[1] == 'F' && this.temp[2] == 'I' && this.temp[3] == 'F'
&& this.temp[4] == '\x00';
this.isJfif = this.Temp[0] == 'J' && this.Temp[1] == 'F' && this.Temp[2] == 'I' && this.Temp[3] == 'F'
&& this.Temp[4] == '\x00';
if (this.isJfif)
{
this.horizontalResolution = (short)(this.temp[9] + (this.temp[10] << 8));
this.verticalResolution = (short)(this.temp[11] + (this.temp[12] << 8));
this.horizontalResolution = (short)(this.Temp[9] + (this.Temp[10] << 8));
this.verticalResolution = (short)(this.Temp[11] + (this.Temp[12] << 8));
}
if (remaining > 0)
@ -1182,7 +1182,7 @@ namespace ImageSharp.Formats
}
}
if (this.isProgressive)
if (this.IsProgressive)
{
if (zigEnd != Block8x8F.ScalarCount - 1 || al != 0)
{
@ -1190,8 +1190,8 @@ namespace ImageSharp.Formats
// TODO!!!
// throw new NotImplementedException();
// this.progCoeffs[compIndex][((@by * mxx) * hi) + bx] = b.Clone();
this.progCoeffs[compIndex][((@by * mxx) * hi) + bx] = *b;
// this.ProgCoeffs[compIndex][((@by * mxx) * hi) + bx] = b.Clone();
this.ProgCoeffs[compIndex][((@by * mxx) * hi) + bx] = *b;
// At this point, we could execute the rest of the loop body to dequantize and
// perform the inverse DCT, to save early stages of a progressive image to the
@ -1234,13 +1234,13 @@ namespace ImageSharp.Formats
totalHv += currentComponent.HorizontalFactor * currentComponent.VerticalFactor;
currentScan.DcTableSelector = (byte)(this.temp[2 + (2 * i)] >> 4);
currentScan.DcTableSelector = (byte)(this.Temp[2 + (2 * i)] >> 4);
if (currentScan.DcTableSelector > HuffmanTree.MaxTh)
{
throw new ImageFormatException("Bad DC table selector value");
}
currentScan.AcTableSelector = (byte)(this.temp[2 + (2 * i)] & 0x0f);
currentScan.AcTableSelector = (byte)(this.Temp[2 + (2 * i)] & 0x0f);
if (currentScan.AcTableSelector > HuffmanTree.MaxTh)
{
throw new ImageFormatException("Bad AC table selector value");
@ -1261,22 +1261,22 @@ namespace ImageSharp.Formats
throw new ImageFormatException("DHT has wrong length");
}
this.ReadFull(this.temp, 0, 17);
this.ReadFull(this.Temp, 0, 17);
int tc = this.temp[0] >> 4;
int tc = this.Temp[0] >> 4;
if (tc > HuffmanTree.MaxTc)
{
throw new ImageFormatException("Bad Tc value");
}
int th = this.temp[0] & 0x0f;
if (th > HuffmanTree.MaxTh || (!this.isProgressive && (th > 1)))
int th = this.Temp[0] & 0x0f;
if (th > HuffmanTree.MaxTh || (!this.IsProgressive && (th > 1)))
{
throw new ImageFormatException("Bad Th value");
}
int huffTreeIndex = (tc * HuffmanTree.ThRowSize) + th;
this.huffmanTrees[huffTreeIndex].ProcessDefineHuffmanTablesMarkerLoop(this, this.temp, ref remaining);
this.huffmanTrees[huffTreeIndex].ProcessDefineHuffmanTablesMarkerLoop(this, this.Temp, ref remaining);
}
}
@ -1292,8 +1292,8 @@ namespace ImageSharp.Formats
throw new ImageFormatException("DRI has wrong length");
}
this.ReadFull(this.temp, 0, 2);
this.restartInterval = ((int)this.temp[0] << 8) + (int)this.temp[1];
this.ReadFull(this.Temp, 0, 2);
this.restartInterval = ((int)this.Temp[0] << 8) + (int)this.Temp[1];
}
/// <summary>
@ -1327,11 +1327,11 @@ namespace ImageSharp.Formats
}
remaining -= Block8x8F.ScalarCount;
this.ReadFull(this.temp, 0, Block8x8F.ScalarCount);
this.ReadFull(this.Temp, 0, Block8x8F.ScalarCount);
for (int i = 0; i < Block8x8F.ScalarCount; i++)
{
this.quantizationTables[tq][i] = this.temp[i];
this.QuantizationTables[tq][i] = this.Temp[i];
}
break;
@ -1343,11 +1343,11 @@ namespace ImageSharp.Formats
}
remaining -= 2 * Block8x8F.ScalarCount;
this.ReadFull(this.temp, 0, 2 * Block8x8F.ScalarCount);
this.ReadFull(this.Temp, 0, 2 * Block8x8F.ScalarCount);
for (int i = 0; i < Block8x8F.ScalarCount; i++)
{
this.quantizationTables[tq][i] = (this.temp[2 * i] << 8) | this.temp[(2 * i) + 1];
this.QuantizationTables[tq][i] = (this.Temp[2 * i] << 8) | this.Temp[(2 * i) + 1];
}
break;
@ -1370,12 +1370,12 @@ namespace ImageSharp.Formats
private void ProcessScanImpl(int i, ref Scan currentScan, Scan[] scan, ref int totalHv)
{
// Component selector.
int cs = this.temp[1 + (2 * i)];
int cs = this.Temp[1 + (2 * i)];
int compIndex = -1;
for (int j = 0; j < this.componentCount; j++)
for (int j = 0; j < this.ComponentCount; j++)
{
// Component compv = ;
if (cs == this.componentArray[j].Identifier)
if (cs == this.ComponentArray[j].Identifier)
{
compIndex = j;
}
@ -1388,7 +1388,7 @@ namespace ImageSharp.Formats
currentScan.Index = (byte)compIndex;
this.ProcessComponentImpl(i, ref currentScan, scan, ref totalHv, ref this.componentArray[compIndex]);
this.ProcessComponentImpl(i, ref currentScan, scan, ref totalHv, ref this.ComponentArray[compIndex]);
}
/// <summary>
@ -1397,7 +1397,7 @@ namespace ImageSharp.Formats
/// <param name="remaining">The remaining bytes in the segment block.</param>
private void ProcessStartOfFrameMarker(int remaining)
{
if (this.componentCount != 0)
if (this.ComponentCount != 0)
{
throw new ImageFormatException("Multiple SOF markers");
}
@ -1405,54 +1405,54 @@ namespace ImageSharp.Formats
switch (remaining)
{
case 6 + (3 * 1): // Grayscale image.
this.componentCount = 1;
this.ComponentCount = 1;
break;
case 6 + (3 * 3): // YCbCr or RGB image.
this.componentCount = 3;
this.ComponentCount = 3;
break;
case 6 + (3 * 4): // YCbCrK or CMYK image.
this.componentCount = 4;
this.ComponentCount = 4;
break;
default:
throw new ImageFormatException("Incorrect number of components");
}
this.ReadFull(this.temp, 0, remaining);
this.ReadFull(this.Temp, 0, remaining);
// We only support 8-bit precision.
if (this.temp[0] != 8)
if (this.Temp[0] != 8)
{
throw new ImageFormatException("Only 8-Bit precision supported.");
}
this.imageHeight = (this.temp[1] << 8) + this.temp[2];
this.imageWidth = (this.temp[3] << 8) + this.temp[4];
if (this.temp[5] != this.componentCount)
this.ImageHeight = (this.Temp[1] << 8) + this.Temp[2];
this.ImageWidth = (this.Temp[3] << 8) + this.Temp[4];
if (this.Temp[5] != this.ComponentCount)
{
throw new ImageFormatException("SOF has wrong length");
}
for (int i = 0; i < this.componentCount; i++)
for (int i = 0; i < this.ComponentCount; i++)
{
this.componentArray[i].Identifier = this.temp[6 + (3 * i)];
this.ComponentArray[i].Identifier = this.Temp[6 + (3 * i)];
// Section B.2.2 states that "the value of C_i shall be different from
// the values of C_1 through C_(i-1)".
for (int j = 0; j < i; j++)
{
if (this.componentArray[i].Identifier == this.componentArray[j].Identifier)
if (this.ComponentArray[i].Identifier == this.ComponentArray[j].Identifier)
{
throw new ImageFormatException("Repeated component identifier");
}
}
this.componentArray[i].Selector = this.temp[8 + (3 * i)];
if (this.componentArray[i].Selector > MaxTq)
this.ComponentArray[i].Selector = this.Temp[8 + (3 * i)];
if (this.ComponentArray[i].Selector > MaxTq)
{
throw new ImageFormatException("Bad Tq value");
}
byte hv = this.temp[7 + (3 * i)];
byte hv = this.Temp[7 + (3 * i)];
int h = hv >> 4;
int v = hv & 0x0f;
if (h < 1 || h > 4 || v < 1 || v > 4)
@ -1465,7 +1465,7 @@ namespace ImageSharp.Formats
throw new ImageFormatException("Lnsupported subsampling ratio");
}
switch (this.componentCount)
switch (this.ComponentCount)
{
case 1:
@ -1512,8 +1512,8 @@ namespace ImageSharp.Formats
case 1:
{
// Cb.
if (this.componentArray[0].HorizontalFactor % h != 0
|| this.componentArray[0].VerticalFactor % v != 0)
if (this.ComponentArray[0].HorizontalFactor % h != 0
|| this.ComponentArray[0].VerticalFactor % v != 0)
{
throw new ImageFormatException("Unsupported subsampling ratio");
}
@ -1524,8 +1524,8 @@ namespace ImageSharp.Formats
case 2:
{
// Cr.
if (this.componentArray[1].HorizontalFactor != h
|| this.componentArray[1].VerticalFactor != v)
if (this.ComponentArray[1].HorizontalFactor != h
|| this.ComponentArray[1].VerticalFactor != v)
{
throw new ImageFormatException("Unsupported subsampling ratio");
}
@ -1565,8 +1565,8 @@ namespace ImageSharp.Formats
break;
case 3:
if (this.componentArray[0].HorizontalFactor != h
|| this.componentArray[0].VerticalFactor != v)
if (this.ComponentArray[0].HorizontalFactor != h
|| this.ComponentArray[0].VerticalFactor != v)
{
throw new ImageFormatException("Unsupported subsampling ratio");
}
@ -1577,11 +1577,18 @@ namespace ImageSharp.Formats
break;
}
this.componentArray[i].HorizontalFactor = h;
this.componentArray[i].VerticalFactor = v;
this.ComponentArray[i].HorizontalFactor = h;
this.ComponentArray[i].VerticalFactor = v;
}
}
private void ProcessStartOfScan22(int remaining)
{
DecoderScanProcessor processor = default(DecoderScanProcessor);
DecoderScanProcessor.Init(&processor, this, remaining);
this.MakeImage(processor.mxx, processor.myy);
}
/// <summary>
/// Processes the SOS (Start of scan marker).
/// </summary>
@ -1595,18 +1602,18 @@ namespace ImageSharp.Formats
/// </exception>
private void ProcessStartOfScan(int remaining)
{
if (this.componentCount == 0)
if (this.ComponentCount == 0)
{
throw new ImageFormatException("Missing SOF marker");
}
if (remaining < 6 || 4 + (2 * this.componentCount) < remaining || remaining % 2 != 0)
if (remaining < 6 || 4 + (2 * this.ComponentCount) < remaining || remaining % 2 != 0)
{
throw new ImageFormatException("SOS has wrong length");
}
this.ReadFull(this.temp, 0, remaining);
byte scanComponentCount = this.temp[0];
this.ReadFull(this.Temp, 0, remaining);
byte scanComponentCount = this.Temp[0];
int scanComponentCountX2 = 2 * scanComponentCount;
if (remaining != 4 + scanComponentCountX2)
@ -1624,7 +1631,7 @@ namespace ImageSharp.Formats
// Section B.2.3 states that if there is more than one component then the
// total H*V values in a scan must be <= 10.
if (this.componentCount > 1 && totalHv > 10)
if (this.ComponentCount > 1 && totalHv > 10)
{
throw new ImageFormatException("Total sampling factors too large.");
}
@ -1648,12 +1655,12 @@ namespace ImageSharp.Formats
int ah = 0;
int al = 0;
if (this.isProgressive)
if (this.IsProgressive)
{
zigStart = this.temp[1 + scanComponentCountX2];
zigEnd = this.temp[2 + scanComponentCountX2];
ah = this.temp[3 + scanComponentCountX2] >> 4;
al = this.temp[3 + scanComponentCountX2] & 0x0f;
zigStart = this.Temp[1 + scanComponentCountX2];
zigEnd = this.Temp[2 + scanComponentCountX2];
ah = this.Temp[3 + scanComponentCountX2] >> 4;
al = this.Temp[3 + scanComponentCountX2] & 0x0f;
if ((zigStart == 0 && zigEnd != 0) || zigStart > zigEnd || zigEnd >= Block8x8F.ScalarCount)
{
@ -1672,24 +1679,22 @@ namespace ImageSharp.Formats
}
// mxx and myy are the number of MCUs (Minimum Coded Units) in the image.
int h0 = this.componentArray[0].HorizontalFactor;
int v0 = this.componentArray[0].VerticalFactor;
int mxx = (this.imageWidth + (8 * h0) - 1) / (8 * h0);
int myy = (this.imageHeight + (8 * v0) - 1) / (8 * v0);
this.MakeImage(mxx, myy);
int h0 = this.ComponentArray[0].HorizontalFactor;
int v0 = this.ComponentArray[0].VerticalFactor;
int mxx = (this.ImageWidth + (8 * h0) - 1) / (8 * h0);
int myy = (this.ImageHeight + (8 * v0) - 1) / (8 * v0);
if (this.isProgressive)
if (this.IsProgressive)
{
for (int i = 0; i < scanComponentCount; i++)
{
int compIndex = scan[i].Index;
if (this.progCoeffs[compIndex] == null)
if (this.ProgCoeffs[compIndex] == null)
{
int size = mxx * myy * this.componentArray[compIndex].HorizontalFactor
* this.componentArray[compIndex].VerticalFactor;
int size = mxx * myy * this.ComponentArray[compIndex].HorizontalFactor
* this.ComponentArray[compIndex].VerticalFactor;
this.progCoeffs[compIndex] = new Block8x8F[size];
this.ProgCoeffs[compIndex] = new Block8x8F[size];
}
}
}
@ -1716,6 +1721,10 @@ namespace ImageSharp.Formats
int* unzigPtr = unzig.Data;
this.MakeImage(mxx, myy);
for (int my = 0; my < myy; my++)
{
for (int mx = 0; mx < mxx; mx++)
@ -1723,8 +1732,8 @@ namespace ImageSharp.Formats
for (int i = 0; i < scanComponentCount; i++)
{
int compIndex = scan[i].Index;
int hi = this.componentArray[compIndex].HorizontalFactor;
int vi = this.componentArray[compIndex].VerticalFactor;
int hi = this.ComponentArray[compIndex].HorizontalFactor;
int vi = this.ComponentArray[compIndex].VerticalFactor;
for (int j = 0; j < hi * vi; j++)
{
@ -1761,24 +1770,24 @@ namespace ImageSharp.Formats
bx = blockCount % q;
by = blockCount / q;
blockCount++;
if (bx * 8 >= this.imageWidth || by * 8 >= this.imageHeight)
if (bx * 8 >= this.ImageWidth || by * 8 >= this.ImageHeight)
{
continue;
}
}
int qtIndex = this.componentArray[compIndex].Selector;
int qtIndex = this.ComponentArray[compIndex].Selector;
// TODO: A DecoderScanProcessor struct could clean up this mess
// TODO: Reading & processing blocks should be done in 2 separate loops. The second one could be parallelized. The first one could be async.
fixed (Block8x8F* qtp = &this.quantizationTables[qtIndex])
fixed (Block8x8F* qtp = &this.QuantizationTables[qtIndex])
{
// Load the previous partially decoded coefficients, if applicable.
if (this.isProgressive)
if (this.IsProgressive)
{
this.blockIndex = ((@by * mxx) * hi) + bx;
fixed (Block8x8F* bp = &this.progCoeffs[compIndex][this.blockIndex])
fixed (Block8x8F* bp = &this.ProgCoeffs[compIndex][this.blockIndex])
{
this.ProcessBlockImpl(
ah,
@ -1835,8 +1844,8 @@ namespace ImageSharp.Formats
{
// A more sophisticated decoder could use RST[0-7] markers to resynchronize from corrupt input,
// but this one assumes well-formed input, and hence the restart marker follows immediately.
this.ReadFull(this.temp, 0, 2);
if (this.temp[0] != 0xff || this.temp[1] != expectedRst)
this.ReadFull(this.Temp, 0, 2);
if (this.Temp[0] != 0xff || this.Temp[1] != expectedRst)
{
throw new ImageFormatException("Bad RST marker");
}
@ -2072,27 +2081,6 @@ namespace ImageSharp.Formats
}
}
/// <summary>
/// Represents a component scan
/// </summary>
private struct Scan
{
/// <summary>
/// Gets or sets the component index.
/// </summary>
public byte Index { get; set; }
/// <summary>
/// Gets or sets the DC table selector
/// </summary>
public byte DcTableSelector { get; set; }
/// <summary>
/// Gets or sets the AC table selector
/// </summary>
public byte AcTableSelector { get; set; }
}
/// <summary>
/// The EOF (End of File exception).
/// Thrown when the decoder encounters an EOF marker without a proceeding EOI (End Of Image) marker

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