/**********************************************************************************
* Returns a new, gaussian-noise corrupted image from the given image
***********************************************************************************/
Image4DSimple* CImageUtils::addGaussianNoise(
Image4DSimple* im, // input image
float w) // gaussian noise weight (1 = only noise, 0 = no noise)
throw (tf::RuntimeException)
{
// checks
if(!im || !im->getRawData())
throw tf::RuntimeException("in CImageUtils::addGaussianNoise(): invalid image data");
if(im->getTDim() > 1)
throw tf::RuntimeException(tf::strprintf("in CImageUtils::addGaussianNoise(): image has TDim = %d (5D not supported)", im->getTDim()));
// allocate new image
Image4DSimple* imout = new Image4DSimple();
imout->setXDim(im->getXDim());
imout->setYDim(im->getYDim());
imout->setZDim(im->getZDim());
imout->setCDim(im->getCDim());
imout->setTDim(im->getTDim());
imout->setDatatype(im->getDatatype());
V3DLONG data_size = imout->getTotalBytes();
unsigned char* data = new unsigned char[data_size];
imout->setRawDataPointer(data);
// data corruption
if(imout->getDatatype() == V3D_UINT8)
{
unsigned char* data_in = im->getRawData();
for(V3DLONG k=0; k<data_size; k++)
data[k] = static_cast<tf::uint8>((1-w)*data_in[k] + w*(rand()%256) +0.5f);
}
else if(imout->getDatatype() == V3D_UINT16)
{
unsigned short* data_in = (unsigned short*)(im->getRawData());
for(V3DLONG k=0; k<data_size/2; k++)
data[k] = static_cast<tf::uint16>((1-w)*data_in[k] + w*(rand()%65535) +0.5f);
}
else
throw tf::RuntimeException("in CImageUtils::addGaussianNoise(): image is neither UINT8 nor UINT16 (not supported)");
return imout;
}
