Constructor
obj = cv.SIFT()
obj = cv.SIFT(..., 'OptionName',optionValue, ...)
Options
- NFeatures The number of best features to retain. The
features are ranked by their scores (measured in SIFT
algorithm as the local contrast). default 0
- NOctaveLayers The number of layers in each octave. 3 is
the value used in D. Lowe paper. The number of octaves is
computed automatically from the image resolution. default 3
- ConstrastThreshold The contrast threshold used to filter
out weak features in semi-uniform (low-contrast) regions. The
larger the threshold, the less features are produced by the
detector. default 0.04
- EdgeThreshold The threshold used to filter out edge-like
features. Note that the its meaning is different from the
ContrastThreshold
, i.e. the larger the EdgeThreshold
, the
less features are filtered out (more features are retained).
default 10
- Sigma The sigma of the Gaussian applied to the input image
at the octave #0. If your image is captured with a weak camera
with soft lenses, you might want to reduce the number.
default 1.6