/// <summary>
///
/// </summary>
/// <param name="stream"></param>
/// <returns></returns>
public static BmpFileHeader FillFromStream(Stream stream)
{
byte[] buffer = new byte[_SIZE];
BmpFileHeader header = new BmpFileHeader();
stream.Read(buffer, 0, _SIZE);
// Fill
header.BitmapType = BitConverter.ToInt16(buffer, 0);
header.Size = BitConverter.ToInt32(buffer, 2);
header.OffsetToData = BitConverter.ToInt32(buffer, 10);
// Return results
return(header);
}
/// <summary>
///
/// </summary>
/// <param name="stream"></param>
/// <returns></returns>
public static BmpFileHeader FillFromStream(Stream stream)
{
byte[] buffer = new byte[_SIZE];
BmpFileHeader header = new BmpFileHeader();
stream.Read(buffer, 0, _SIZE);
// Fill
header.BitmapType = BitConverter.ToInt16(buffer, 0);
header.Size = BitConverter.ToInt32(buffer, 2);
header.OffsetToData = BitConverter.ToInt32(buffer, 10);
// Return results
return header;
}
/// <summary>
/// Decodes a bitmap stream into an editable image.
/// </summary>
/// <param name="stream"></param>
/// <returns></returns>
public static EditableImage Decode(Stream stream)
{
EditableImage image = null;
// See http://en.wikipedia.org/wiki/BMP_file_format
try
{
byte[] buffer;
BmpFileHeader fHeader;
BmpInfoHeader iHeader;
// Read File Header
fHeader = BmpFileHeader.FillFromStream(stream);
// Validate file type
if (fHeader.BitmapType != 19778)
{
throw new Exception("Invalid BMP file");
}
// Read Info Header
iHeader = BmpInfoHeader.FillFromStream(stream);
// Data
if ((iHeader.Compression == 0) && (iHeader.BitsPerPixel == 24))
{
// Read bits into the buffer
buffer = new byte[iHeader.ImageSize];
stream.Read(buffer, 0, iHeader.ImageSize);
// Standard RGB file
image = Read24BitBmp(buffer, iHeader);
}
else if ((iHeader.Compression == 0) && (iHeader.BitsPerPixel <= 8))
{
int count = iHeader.ColorCount * 4; // 4 bytes per color
Color[] palette;
// Read colors
buffer = new byte[count];
stream.Read(buffer, 0, count);
palette = FillColorPalette(buffer, iHeader.ColorCount);
// Read data
buffer = new byte[iHeader.ImageSize];
stream.Read(buffer, 0, iHeader.ImageSize);
image = ReadPaletteBmp(buffer, palette, iHeader, iHeader.BitsPerPixel);
}
else if ((iHeader.Compression == 3) && (iHeader.BitsPerPixel == 16))
{
// Special 565 16 bit encoding - see http://www.virtualdub.org/blog/pivot/entry.php?id=177
int remainder = fHeader.OffsetToData - (int)stream.Position;
int rMask;
int bMask;
int gMask;
// Read remainder
buffer = new byte[remainder];
stream.Read(buffer, 0, remainder);
// Read masks
rMask = BitConverter.ToInt32(buffer, 0);
gMask = BitConverter.ToInt32(buffer, 4);
bMask = BitConverter.ToInt32(buffer, 8);
if ((_REDMASK != rMask) || (_GREENMASK != gMask) || (_BLUEMASK != bMask))
{
// Not 565 format
throw new Exception("Unsupported 16 bit format: " + rMask.ToString("X2") + ", " + bMask.ToString("X2") + ", " + gMask.ToString("X2"));
}
// Read data
remainder = iHeader.Height * iHeader.Width * 2; // 2 bytes per pixel
buffer = new byte[remainder];
stream.Read(buffer, 0, remainder);
// Convert to an image
image = Read565Bmp(buffer, iHeader);
}
else
{
throw new Exception("Unsupported format (compression: " + iHeader.Compression.ToString() + ", Bits per pixel: " + iHeader.BitsPerPixel.ToString() + ")");
}
}
catch (Exception ex)
{
#if SILVERLIGHT
HtmlPage.Window.Alert("Error parsing BMP file: " + ex.Message);
#else
throw;
#endif
}
return(image);
}
