VL_INLINE
void _vl_dsift_with_flat_window (VlDsiftFilter* self)
{
int binx, biny, bint ;
int framex, framey ;
/* for each orientation bin */
for (bint = 0 ; bint < self->geom.numBinT ; ++bint) {
vl_imconvcoltri_vf (self->convTmp1, self->imHeight,
self->grads [bint], self->imWidth, self->imHeight,
self->imWidth,
self->geom.binSizeY - 1, /* filt size */
1, /* subsampling step */
VL_PAD_BY_CONTINUITY|VL_TRANSPOSE) ;
vl_imconvcoltri_vf (self->convTmp2, self->imWidth,
self->convTmp1, self->imHeight, self->imWidth,
self->imHeight,
self->geom.binSizeX - 1,
1,
VL_PAD_BY_CONTINUITY|VL_TRANSPOSE) ;
for (biny = 0 ; biny < self->geom.numBinY ; ++biny) {
for (binx = 0 ; binx < self->geom.numBinX ; ++binx) {
float *dst = self->descrs
+ bint
+ binx * self->geom.numBinT
+ biny * (self->geom.numBinX * self->geom.numBinT) ;
float *src = self->convTmp2 ;
int frameSizeX = self->geom.binSizeX * (self->geom.numBinX - 1) + 1 ;
int frameSizeY = self->geom.binSizeY * (self->geom.numBinY - 1) + 1 ;
int descrSize = vl_dsift_get_descriptor_size (self) ;
for (framey = self->boundMinY ;
framey <= self->boundMaxY - frameSizeY + 1 ;
framey += self->stepY) {
for (framex = self->boundMinX ;
framex <= self->boundMaxX - frameSizeX + 1 ;
framex += self->stepX) {
*dst = src [(framex + binx * self->geom.binSizeX) * 1 +
(framey + biny * self->geom.binSizeY) * self->imWidth] ;
dst += descrSize ;
} /* framex */
} /* framey */
} /* binx */
} /* biny */
} /* bint */
}
VL_INLINE
void _vl_dsift_with_flat_window (VlDsiftFilter* self)
{
int binx, biny, bint ;
int framex, framey ;
/* for each orientation bin */
for (bint = 0 ; bint < self->geom.numBinT ; ++bint) {
vl_imconvcoltri_vf (self->convTmp1, self->imHeight,
self->grads [bint], self->imWidth, self->imHeight,
self->imWidth,
self->geom.binSizeY, /* filt size */
1, /* subsampling step */
VL_PAD_BY_CONTINUITY|VL_TRANSPOSE) ;
vl_imconvcoltri_vf (self->convTmp2, self->imWidth,
self->convTmp1, self->imHeight, self->imWidth,
self->imHeight,
self->geom.binSizeX,
1,
VL_PAD_BY_CONTINUITY|VL_TRANSPOSE) ;
for (biny = 0 ; biny < self->geom.numBinY ; ++biny) {
float wy = _vl_dsift_get_bin_window_mean (self->geom.binSizeY,
self->geom.numBinY,
biny,
self->windowSize) ;
/* The convolution function uses triangualr wave with unit integral (hence height
* equal to half the bin size). Instead
* for SIFT the triangular wave is used as a partition function and must
* have unit maximum. We compoensate for this by multiplying the result
* by the bin size.
*/
wy *= self->geom.binSizeY ;
for (binx = 0 ; binx < self->geom.numBinX ; ++binx) {
float w ;
float wx = _vl_dsift_get_bin_window_mean (self->geom.binSizeX,
self->geom.numBinX,
binx,
self->windowSize) ;
float *dst = self->descrs
+ bint
+ binx * self->geom.numBinT
+ biny * (self->geom.numBinX * self->geom.numBinT) ;
float *src = self->convTmp2 ;
int frameSizeX = self->geom.binSizeX * (self->geom.numBinX - 1) + 1 ;
int frameSizeY = self->geom.binSizeY * (self->geom.numBinY - 1) + 1 ;
int descrSize = vl_dsift_get_descriptor_size (self) ;
wx *= self->geom.binSizeX ;
w = wx * wy ;
for (framey = self->boundMinY ;
framey <= self->boundMaxY - frameSizeY + 1 ;
framey += self->stepY) {
for (framex = self->boundMinX ;
framex <= self->boundMaxX - frameSizeX + 1 ;
framex += self->stepX) {
*dst = w * src [(framex + binx * self->geom.binSizeX) * 1 +
(framey + biny * self->geom.binSizeY) * self->imWidth] ;
dst += descrSize ;
} /* framex */
} /* framey */
} /* binx */
} /* biny */
} /* bint */
}
