private void WriteXorBitmap(BufferedImage img)
{
Raster raster = img.getRaster();
switch (img.getColorModel().getPixelSize())
{
case 1:
Write1(raster);
break;
case 4:
Write4(raster);
break;
case 8:
Write8(raster);
break;
case 24:
Write24(raster);
break;
case 32:
Raster alpha = img.getAlphaRaster();
Write32(raster, alpha);
break;
}
}
/// <summary>
/// Encodes the <em>AND</em> bitmap for the given image according the its
/// alpha channel (transparency) and writes it to the given output.
/// </summary>
/// <param name="img">
/// the image to encode as the <em>AND</em> bitmap. </param>
private void WriteAndBitmap(BufferedImage img)
{
WritableRaster alpha = img.getAlphaRaster();
// indexed transparency (eg. GIF files)
if (img.getColorModel() is IndexColorModel && img.getColorModel().hasAlpha())
{
int w = img.getWidth();
int h = img.getHeight();
int bytesPerLine = GetBytesPerLine1(w);
byte[] line = new byte[bytesPerLine];
IndexColorModel icm = (IndexColorModel)img.getColorModel();
Raster raster = img.getRaster();
for (int y = h - 1; y >= 0; y--)
{
for (int x = 0; x < w; x++)
{
int bi = x / 8;
int i = x % 8;
// int a = alpha.getSample(x, y, 0);
int p = raster.getSample(x, y, 0);
int a = icm.getAlpha(p);
// invert bit since and mask is applied to xor mask
int b = ~a & 1;
line[bi] = SetBit(line[bi], i, b);
}
writer.Write(line);
}
}
// no transparency
else if (alpha == null)
{
int h = img.getHeight();
int w = img.getWidth();
// calculate number of bytes per line, including 32-bit padding
int bytesPerLine = GetBytesPerLine1(w);
byte[] line = new byte[bytesPerLine];
for (int i = 0; i < bytesPerLine; i++)
{
line[i] = (byte)0;
}
for (int y = h - 1; y >= 0; y--)
{
writer.Write(line);
}
}
// transparency (ARGB, etc. eg. PNG)
else
{
int w = img.getWidth();
int h = img.getHeight();
int bytesPerLine = GetBytesPerLine1(w);
byte[] line = new byte[bytesPerLine];
for (int y = h - 1; y >= 0; y--)
{
for (int x = 0; x < w; x++)
{
int bi = x / 8;
int i = x % 8;
int a = alpha.getSample(x, y, 0);
// invert bit since and mask is applied to xor mask
int b = ~a & 1;
line[bi] = SetBit(line[bi], i, b);
}
writer.Write(line);
}
}
}
