/// <summary>
/// Compresses the image data.
/// </summary>
public void CompressImageData()
{
// Do not recompress if compressed data is already present.
if (ImageDataRaw != null)
{
return;
}
if (ImageData == null)
{
return;
}
if (ImageCompression == ImageCompression.Rle)
{
RleRowLengths = new RleRowLengths(Rect.Height);
}
var compressor = ImageDataFactory.Create(this, null);
compressor.Write(ImageData);
ImageDataRaw = compressor.ReadCompressed();
Length = 2 + ImageDataRaw.Length;
if (ImageCompression == ImageCompression.Rle)
{
var rowLengthSize = Layer.PsdFile.IsLargeDocument ? 4 : 2;
Length += rowLengthSize * Rect.Height;
}
}
//////////////////////////////////////////////////////////////////
internal void LoadPixelData(PsdBinaryReader reader)
{
var endPosition = reader.BaseStream.Position + this.Length;
ImageCompression = (ImageCompression)reader.ReadInt16();
var dataLength = this.Length - 2;
switch (ImageCompression)
{
case ImageCompression.Raw:
ImageDataRaw = reader.ReadBytes(dataLength);
break;
case ImageCompression.Rle:
// RLE row lengths
RleRowLengths = new RleRowLengths(reader, (int)Rect.height);
var rleDataLength = (int)(endPosition - reader.BaseStream.Position);
// 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;
}
}
//internal void Save(PsdBinaryWriter writer)
//{
// Util.DebugMessage(writer.BaseStream, "Save, Begin, Channel");
// writer.Write(ID);
// if (Layer.PsdFile.IsLargeDocument)
// {
// writer.Write(Length);
// }
// else
// {
// writer.Write((Int32)Length);
// }
// Util.DebugMessage(writer.BaseStream, "Save, 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 + this.Length;
ImageCompression = (ImageCompression)reader.ReadInt16();
var longDataLength = this.Length - 2;
Util.CheckByteArrayLength(longDataLength);
var dataLength = (int)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 = (int)(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.");
}
/// <summary>
/// Compresses the image data.
/// </summary>
public void CompressImageData()
{
// Do not recompress if compressed data is already present.
if (ImageDataRaw != null)
{
return;
}
if (ImageData == null)
{
return;
}
if (ImageCompression == ImageCompression.Raw)
{
ImageDataRaw = ImageData;
this.Length = 2 + ImageDataRaw.Length;
}
else if (ImageCompression == ImageCompression.Rle)
{
RleRowLengths = new RleRowLengths((int)Rect.height);
using (var dataStream = new MemoryStream())
{
var rleWriter = new RleWriter(dataStream);
var bytesPerRow = Util.BytesPerRow(Rect, Layer.PsdFile.BitDepth);
for (int row = 0; row < Rect.height; row++)
{
int rowIndex = row * (int)Rect.width;
RleRowLengths[row] = rleWriter.Write(
ImageData, rowIndex, bytesPerRow);
}
// Save compressed data
dataStream.Flush();
ImageDataRaw = dataStream.ToArray();
}
Length = 2 + 2 * (int)Rect.height + ImageDataRaw.Length;
}
else
{
throw new NotImplementedException("Only raw and RLE compression have been implemented.");
}
}
