///////////////////////////////////////////////////////////////////////////
private void LoadHeader(PsdBinaryReader reader)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, File header");
var signature = reader.ReadAsciiChars(4);
if (signature != "8BPS")
{
throw new PsdInvalidException("The given stream is not a valid PSD file");
}
Version = (PsdFileVersion)reader.ReadInt16();
Util.DebugMessage(reader.BaseStream, "Load, Info, Version {0}", (int)Version);
if ((Version != PsdFileVersion.Psd) &&
(Version != PsdFileVersion.PsbLargeDocument))
{
throw new PsdInvalidException("The PSD file has an unknown version");
}
//6 bytes reserved
reader.BaseStream.Position += 6;
this.ChannelCount = reader.ReadInt16();
this.RowCount = reader.ReadInt32();
this.ColumnCount = reader.ReadInt32();
BitDepth = reader.ReadInt16();
ColorMode = (PsdColorMode)reader.ReadInt16();
Util.DebugMessage(reader.BaseStream, "Load, End, File header");
}
public ResolutionInfo(PsdBinaryReader reader, string name)
: base(name)
{
this.HDpi = new UFixed1616(reader.ReadUInt32());
this.HResDisplayUnit = (ResUnit)reader.ReadInt16();
this.WidthDisplayUnit = (Unit)reader.ReadInt16();
this.VDpi = new UFixed1616(reader.ReadUInt32());
this.VResDisplayUnit = (ResUnit)reader.ReadInt16();
this.HeightDisplayUnit = (Unit)reader.ReadInt16();
}
internal Channel(PsdBinaryReader reader, Layer layer)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Channel");
ID = reader.ReadInt16();
Length = (layer.PsdFile.IsLargeDocument)
? reader.ReadInt64()
: reader.ReadInt32();
Layer = layer;
Util.DebugMessage(reader.BaseStream, "Load, End, Channel, {0}", ID);
}
//////////////////////////////////////////////////////////////////
internal void LoadPixelData(PsdBinaryReader reader)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Channel image");
if (Length == 0)
{
ImageCompression = ImageCompression.Raw;
ImageDataRaw = new Byte[0];
return;
}
var endPosition = reader.BaseStream.Position + Length;
ImageCompression = (ImageCompression)reader.ReadInt16();
var longDataLength = Length - 2;
Util.CheckByteArrayLength(longDataLength);
var dataLength = (Int32)longDataLength;
switch (ImageCompression)
{
case ImageCompression.Raw:
ImageDataRaw = reader.ReadBytes(dataLength);
break;
case ImageCompression.Rle:
// RLE row lengths
RleRowLengths = new RleRowLengths(reader, Rect.Height,
Layer.PsdFile.IsLargeDocument);
var rleDataLength = (Int32)(endPosition - reader.BaseStream.Position);
Debug.Assert(rleDataLength == RleRowLengths.Total,
"RLE row lengths do not sum to length of channel image data.");
// The PSD specification states that rows are padded to even sizes.
// However, Photoshop doesn't actually do this. RLE rows can have
// odd lengths in the header, and there is no padding between rows.
ImageDataRaw = reader.ReadBytes(rleDataLength);
break;
case ImageCompression.Zip:
case ImageCompression.ZipPrediction:
ImageDataRaw = reader.ReadBytes(dataLength);
break;
}
Util.DebugMessage(reader.BaseStream, "Load, End, Channel image, {0}",
ID, Layer.Name);
Debug.Assert(reader.BaseStream.Position == endPosition,
"Pixel data was not fully read in.");
}
private void LoadImage(PsdBinaryReader reader)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Composite image");
ImageCompression = (ImageCompression)reader.ReadInt16();
// Create channels
for (Int16 i = 0; i < ChannelCount; i++)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Channel image data");
var channel = new Channel(i, this.BaseLayer);
channel.ImageCompression = ImageCompression;
channel.Length = this.RowCount
* Util.BytesPerRow(BaseLayer.Rect.Size, BitDepth);
// The composite image stores all RLE headers up-front, rather than
// with each channel.
if (ImageCompression == ImageCompression.Rle)
{
channel.RleRowLengths = new RleRowLengths(reader, RowCount, IsLargeDocument);
channel.Length = channel.RleRowLengths.Total;
}
BaseLayer.Channels.Add(channel);
Util.DebugMessage(reader.BaseStream, "Load, End, Channel image data");
}
foreach (var channel in this.BaseLayer.Channels)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Channel image data");
Util.CheckByteArrayLength(channel.Length);
channel.ImageDataRaw = reader.ReadBytes((int)channel.Length);
Util.DebugMessage(reader.BaseStream, "Load, End, Channel image data");
}
// If there is exactly one more channel than we need, then it is the
// alpha channel.
if ((ColorMode != PsdColorMode.Multichannel) &&
(ChannelCount == ColorMode.MinChannelCount() + 1))
{
var alphaChannel = BaseLayer.Channels.Last();
alphaChannel.ID = -1;
}
Util.DebugMessage(reader.BaseStream, "Load, End, Composite image");
}
///////////////////////////////////////////////////////////////////////////
/// <summary>
/// Load Layers Info section, including image data.
/// </summary>
/// <param name="reader">PSD reader.</param>
/// <param name="hasHeader">Whether the Layers Info section has a length header.</param>
internal void LoadLayers(PsdBinaryReader reader, bool hasHeader)
{
Util.DebugMessage(reader.BaseStream, "Load, Begin, Layers Info section");
long sectionLength = 0;
if (hasHeader)
{
sectionLength = IsLargeDocument
? reader.ReadInt64()
: reader.ReadUInt32();
if (sectionLength <= 0)
{
// The callback may take action when there are 0 layers, so it must
// be called even though the Layers Info section is empty.
LoadContext.OnLoadLayersHeader(this);
Util.DebugMessage(reader.BaseStream, "Load, End, Layers Info section");
return;
}
}
var startPosition = reader.BaseStream.Position;
var numLayers = reader.ReadInt16();
// If numLayers < 0, then number of layers is absolute value,
// and the first alpha channel contains the transparency data for
// the merged result.
if (numLayers < 0)
{
AbsoluteAlpha = true;
numLayers = Math.Abs(numLayers);
}
for (int i = 0; i < numLayers; i++)
{
var layer = new Layer(reader, this);
Layers.Add(layer);
}
// Header is complete just before loading pixel data
LoadContext.OnLoadLayersHeader(this);
//-----------------------------------------------------------------------
// Load image data for all channels.
foreach (var layer in Layers)
{
Util.DebugMessage(reader.BaseStream,
$"Load, Begin, Layer image, {layer.Name}");
foreach (var channel in layer.Channels)
{
channel.LoadPixelData(reader);
}
Util.DebugMessage(reader.BaseStream,
$"Load, End, Layer image, {layer.Name}");
}
// Length is set to 0 when called on higher bitdepth layers.
if (sectionLength > 0)
{
// Layers Info section is documented to be even-padded, but Photoshop
// actually pads to 4 bytes.
var endPosition = startPosition + sectionLength;
var positionOffset = reader.BaseStream.Position - endPosition;
Debug.Assert(positionOffset > -4,
"LoadLayers did not read the full length of the Layers Info section.");
Debug.Assert(positionOffset <= 0,
"LoadLayers read past the end of the Layers Info section.");
if (reader.BaseStream.Position < endPosition)
{
reader.BaseStream.Position = endPosition;
}
}
Util.DebugMessage(reader.BaseStream, "Load, End, Layers");
}
