def extract(self, impath):
""" Extract a ScSPM descriptor for an image.
This method will return an ScSPM descriptor for an image.
learn_dictionary() needs to be run (once) before this method can be
used.
Arguments:
impath: str, the path to an image
Returns:
a ScSPM descriptor (array) for the image. This array either has
self.dsize*sum(self.levels**2) elements, or self.compress_dim if
not None.
"""
if self.dic is None:
raise ValueError('No dictionary has been learned!')
# Get and resize image
img = pch.imread_resize(impath, self.maxdim)
# Extract SIFT patches
patches, cx, cy = sw.DSIFT_patches(img, self.psize, self.pstride)
# Get OMP codes
scpatch = np.transpose(
omp(np.asfortranarray(patches.T, np.float64),
self.dic,
self.active,
eps=np.spacing(1),
numThreads=1).todense())
# Pyramid pooling and normalisation
fea = pch.pyramid_pooling(scpatch, cx, cy, img.shape, self.levels)
fea = fea / math.sqrt((fea**2).sum() + 1e-10)
if self.compress_dim is not None:
return np.dot(fea, self.rmat)
else:
return fea
def extract (self, impath):
""" Extract a ScSPM descriptor for an image.
This method will return an ScSPM descriptor for an image.
learn_dictionary() needs to be run (once) before this method can be
used.
Arguments:
impath: str, the path to an image
Returns:
a ScSPM descriptor (array) for the image. This array either has
self.dsize*sum(self.levels**2) elements, or self.compress_dim if
not None.
"""
if self.dic is None:
raise ValueError('No dictionary has been learned!')
# Get and resize image
img = pch.imread_resize(impath, self.maxdim)
# Extract SIFT patches
patches, cx, cy = sw.DSIFT_patches(img, self.psize, self.pstride)
# Get OMP codes
scpatch = np.transpose(omp(np.asfortranarray(patches.T, np.float64),
self.dic, self.active, eps=np.spacing(1),
numThreads=1).todense())
# Pyramid pooling and normalisation
fea = pch.pyramid_pooling(scpatch, cx, cy, img.shape, self.levels)
fea = fea / math.sqrt((fea**2).sum() + 1e-10)
if self.compress_dim is not None:
return np.dot(fea, self.rmat)
else:
return fea
def test_pyramid_pooling (self):
""" Test the imgpatches.pyramid_pooling function. """
pyr = patch.pyramid_pooling(self.tpatch, self.tx, self.ty,
self.timg.shape, (1,2), patch.p_max)
self.assertTrue((self.tpyr == pyr).all())
