private static IReadWriteBitmapData?DoLoadBitmapData(IAsyncContext context, Stream stream)
{
context.Progress?.New(DrawingOperation.Loading, 1000);
var reader = new BinaryReader(stream);
if (reader.ReadInt32() != magicNumber)
{
throw new ArgumentException(Res.ImagingNotBitmapDataStream, nameof(stream));
}
var size = new Size(reader.ReadInt32(), reader.ReadInt32());
var pixelFormat = (PixelFormat)reader.ReadInt32();
Color32 backColor = Color32.FromArgb(reader.ReadInt32());
byte alphaThreshold = reader.ReadByte();
Palette?palette = null;
int paletteLength = reader.ReadInt32();
if (paletteLength > 0)
{
var entries = new Color32[paletteLength];
for (int i = 0; i < paletteLength; i++)
{
entries[i] = Color32.FromArgb(reader.ReadInt32());
}
palette = new Palette(entries, backColor, alphaThreshold);
}
context.Progress?.SetProgressValue((int)(stream.Position * 1000 / stream.Length));
if (context.IsCancellationRequested)
{
return(null);
}
IBitmapDataInternal result = CreateManagedBitmapData(size, pixelFormat, backColor, alphaThreshold, palette);
int bpp = pixelFormat.ToBitsPerPixel();
bool canceled = false;
try
{
IBitmapDataRowInternal row = result.DoGetRow(0);
for (int y = 0; y < result.Height; y++)
{
if (canceled = context.IsCancellationRequested)
{
return(null);
}
switch (bpp)
{
case 32:
for (int x = 0; x < result.Width; x++)
{
row.DoWriteRaw(x, reader.ReadInt32());
}
break;
case 16:
for (int x = 0; x < result.Width; x++)
{
row.DoWriteRaw(x, reader.ReadInt16());
}
break;
case 64:
for (int x = 0; x < result.Width; x++)
{
row.DoWriteRaw(x, reader.ReadInt64());
}
break;
default:
for (int x = 0; x < result.RowSize; x++)
{
row.DoWriteRaw(x, reader.ReadByte());
}
break;
}
row.MoveNextRow();
context.Progress?.SetProgressValue((int)(stream.Position * 1000 / stream.Length));
}
return((canceled = context.IsCancellationRequested) ? null : result);
}
finally
{
if (canceled)
{
result.Dispose();
}
}
}
public static Color64 FromArgb32(int argb) => new Color64(Color32.FromArgb(argb));