public override ImageData Read(Stream stream, ImageMetaData info)
{
var meta = info as GrdMetaData;
if (null == meta)
throw new ArgumentException ("GrdFormat.Read should be supplied with GrdMetaData", "info");
stream.Position = 12;
using (var reader = new Reader (stream, meta.DataSize))
{
reader.Unpack();
byte[] pixels = reader.Data;
using (var bmp = new MemoryStream (reader.Data, false))
{
var decoder = new BmpBitmapDecoder (bmp,
BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
BitmapSource frame = decoder.Frames[0];
frame.Freeze();
return new ImageData (frame, info);
}
}
}
public override ImageMetaData ReadMetaData(Stream stream)
{
stream.Seek (4, SeekOrigin.Current);
int data_size = stream.ReadByte() | stream.ReadByte() << 8 | stream.ReadByte() << 16 | stream.ReadByte() << 24;
stream.Seek (4, SeekOrigin.Current);
using (var reader = new Reader (stream, 0x22)) // BMP header
{
reader.Unpack();
var bmp = reader.Data;
if (bmp[0] != 'B' || bmp[1] != 'M')
return null;
int width = LittleEndian.ToInt32 (bmp, 0x12);
int height = LittleEndian.ToInt32 (bmp, 0x16);
int bpp = LittleEndian.ToInt16 (bmp, 0x1c);
return new GrdMetaData
{
Width = (uint)width,
Height = (uint)height,
BPP = bpp,
DataSize = data_size,
};
}
}