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SIFT feature extractor
sf = isift(im, options) is a vector of SiftPointFeature objects representing scale and rotationally invariant interest points in the image im.
'nfeat', N | set the number of features to return (default Inf) |
'suppress', R | set the suppression radius (default 0) |
'id', V | set the image_id of all features |
The SiftPointFeature object has many properties including:
u | horizontal coordinate |
v | vertical coordinate |
strength | feature strength |
descriptor | feature descriptor (128x1) |
sigma | feature scale |
theta | feature orientation [rad] |
image_id | a value passed as an option to ISIFT |
The SiftPointFeature object has many methods including:
plot | Plot feature position |
plot_scale | Plot feature scale |
distance | Descriptor distance |
match | Match features |
ncc | Descriptor similarity |
See SiftPointFeature and PointFeature classes for more details.
"Distinctive image features from scale-invariant keypoints", David G. Lowe, International Journal of Computer Vision, 60, 2 (2004), pp. 91-110.
SiftPointFeature, isurf, icorner
© 1990-2012 Peter Corke.