public PsdFile(string filename, LoadContext loadContext)
: this()
{
using (var stream = new FileStream(filename, FileMode.Open))
{
Load(stream, loadContext);
}
}
private void Load(Stream stream, LoadContext loadContext)
{
LoadContext = loadContext;
var reader = new PsdBinaryReader(stream, loadContext.Encoding);
LoadHeader(reader);
LoadColorModeData(reader);
LoadImageResources(reader);
LoadLayerAndMaskInfo(reader);
LoadImage(reader);
DecompressImages();
}
public PsdFile(Stream stream, LoadContext loadContext)
: this()
{
Load(stream, loadContext);
}
///////////////////////////////////////////////////////////////////////////
/// <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");
}