private void EmbedWatermark(double[,] data)
{
double[,] watermarkData = new double[_watermarkPixels.Width, _watermarkPixels.Height];
//convet 32*32 watermark picture to black and white only (102->black(0);922->wthite(255))
for (int x = 0; x < _watermarkPixels.Width; x++)
{
for (int y = 0; y < _watermarkPixels.Height; y++)
{
watermarkData[x, y] = _watermarkPixels.R[x, y] > 125 ? 255 : 0;//convert to black or white only
}
}
//test
//ParallelHaar.FWT(data, 2);
//var subband = LL2(data);
var subband = data;
Parallel.For(0, _watermarkPixels.Height, y => //height = 32
{
for (int x = 0; x < _watermarkPixels.Width; x++) //width = 32
{
//BlockSize = 4
var block = subband.Submatrix(x * BlockSize, x * BlockSize + BlockSize - 1, y * BlockSize, y * BlockSize + BlockSize - 1);
CosineTransform.DCT(block);//DCT here
var midbandSum = Math.Max(2, Math.Abs(MidBand(block).Sum()));
var sigma = (watermarkData[x, y] > 125 ? 3 : -3);
block[1, 2] += midbandSum * sigma;
block[2, 0] += midbandSum * sigma;
block[2, 1] += midbandSum * sigma;
block[2, 2] += midbandSum * sigma;
CosineTransform.IDCT(block);
for (int i = 0; i < BlockSize; i++)
{
for (int j = 0; j < BlockSize; j++)
{
subband[x * BlockSize + i, y * BlockSize + j] = block[i, j];
}
}
}
});
BackApplySubBand(data, subband);
ParallelHaar.IWT(data, 2);
}//end EmbedWatermark
private void EmbedWatermark(double[,] data)
{
double[,] watermarkData = new double[_watermarkPixels.Width, _watermarkPixels.Height];
for (int x = 0; x < _watermarkPixels.Width; x++)
{
for (int y = 0; y < _watermarkPixels.Height; y++)
{
watermarkData[x, y] = _watermarkPixels.R[x, y] > 125 ? 255 : 0;
}
}
ParallelHaar.FWT(data, 2);
var subband = LL2(data);
Parallel.For(0, _watermarkPixels.Height, y =>
{
for (int x = 0; x < _watermarkPixels.Width; x++)
{
var block = subband.Submatrix(x * BlockSize, x * BlockSize + BlockSize - 1, y * BlockSize, y * BlockSize + BlockSize - 1);
CosineTransform.DCT(block);
var midbandSum = Math.Max(2, Math.Abs(MidBand(block).Sum()));
var sigma = (watermarkData[x, y] > 125 ? 3 : -3);
block[1, 2] += midbandSum * sigma;
block[2, 0] += midbandSum * sigma;
block[2, 1] += midbandSum * sigma;
block[2, 2] += midbandSum * sigma;
CosineTransform.IDCT(block);
for (int i = 0; i < BlockSize; i++)
{
for (int j = 0; j < BlockSize; j++)
{
subband[x * BlockSize + i, y * BlockSize + j] = block[i, j];
}
}
}
});
BackApplySubBand(data, subband);
ParallelHaar.IWT(data, 2);
}