void HighPassFilter::applyLowPass(const Image2DPtr &image)
{
// Guassian convolution can be separated in two 1D convolution
// because of properties of the 2D Gaussian function.
Image2DPtr temp = Image2D::CreateZeroImagePtr(image->Width(), image->Height());
size_t hKernelMid = _hWindowSize/2;
for(size_t i=0; i<_hWindowSize; ++i) {
const num_t kernelValue = _hKernel[i];
const size_t
xStart = (i >= hKernelMid) ? 0 : (hKernelMid-i),
xEnd = (i <= hKernelMid) ? image->Width() : image->Width()-i+hKernelMid;
for(unsigned y=0;y<image->Height();++y) {
for(unsigned x=xStart;x<xEnd;++x)
temp->AddValue(x, y, image->Value(x+i-hKernelMid, y)*kernelValue);
}
}
image->SetAll(0.0);
size_t vKernelMid = _vWindowSize/2;
for(size_t i=0; i<_vWindowSize; ++i) {
const num_t kernelValue = _vKernel[i];
const size_t
yStart = (i >= vKernelMid) ? 0 : (vKernelMid-i),
yEnd = (i <= vKernelMid) ? image->Height() : image->Height()-i+vKernelMid;
for(unsigned y=yStart;y<yEnd;++y) {
for(unsigned x=0;x<image->Width();++x)
image->AddValue(x, y, temp->Value(x, y+i-vKernelMid)*kernelValue);
}
}
}
void HighPassFilter::applyLowPassSSE(const Image2DPtr &image)
{
Image2DPtr temp = Image2D::CreateZeroImagePtr(image->Width(), image->Height());
unsigned hKernelMid = _hWindowSize/2;
for(unsigned i=0; i<_hWindowSize; ++i) {
const num_t k = _hKernel[i];
const __m128 k4 = _mm_set_ps(k, k, k, k);
unsigned
/* xStart is the first column to start writing to. Note that it might be larger
* than the width. */
xStart = (i >= hKernelMid) ? 0 : (hKernelMid-i),
xEnd = (i <= hKernelMid) ? image->Width() : (image->Width()+hKernelMid > i ? (image->Width()-i+hKernelMid) : 0);
for(unsigned y=0;y<image->Height();++y) {
float *tempPtr = temp->ValuePtr(xStart, y);
const float *imagePtr = image->ValuePtr(xStart+i-hKernelMid, y);
unsigned x = xStart;
for(;x+4<xEnd;x+=4) {
const __m128
imageVal = _mm_loadu_ps(imagePtr),
tempVal = _mm_loadu_ps(tempPtr);
// *tempPtr += k * (*imagePtr);
_mm_storeu_ps(tempPtr, _mm_add_ps(tempVal, _mm_mul_ps(imageVal, k4)));
tempPtr += 4;
imagePtr += 4;
}
for(;x<xEnd;++x) {
*tempPtr += k * (*imagePtr);
++tempPtr;
++imagePtr;
}
}
}
image->SetAll(0.0);
unsigned vKernelMid = _vWindowSize/2;
for(unsigned i=0; i<_vWindowSize; ++i) {
const num_t k = _vKernel[i];
const __m128 k4 = _mm_set_ps(k, k, k, k);
const unsigned
yStart = (i >= vKernelMid) ? 0 : (vKernelMid-i),
yEnd = (i <= vKernelMid) ? image->Height() : ((image->Height()+vKernelMid>i) ? (image->Height()-i+vKernelMid) : 0);
for(unsigned y=yStart;y<yEnd;++y) {
const float *tempPtr = temp->ValuePtr(0, y+i-vKernelMid);
float *imagePtr = image->ValuePtr(0, y);
unsigned x=0;
for(;x+4<image->Width();x += 4) {
const __m128
imageVal = _mm_load_ps(imagePtr),
tempVal = _mm_load_ps(tempPtr);
// *imagePtr += k * (*tempPtr);
_mm_store_ps(imagePtr, _mm_add_ps(imageVal, _mm_mul_ps(tempVal, k4)));
tempPtr += 4;
imagePtr += 4;
}
for(;x<image->Width();++x) {
*imagePtr += k * (*tempPtr);
++tempPtr;
++imagePtr;
}
}
}
}
