VL_PLOTSIFTDESCRIPTOR(D) plots the SIFT descriptor D. If D is a matrix, it plots one descriptor per column. D has the same format used by VL_SIFT().

VL_PLOTSIFTDESCRIPTOR(D,F) plots the SIFT descriptors warped to the SIFT frames F, specified as columns of the matrix F. F has the same format used by VL_SIFT().

H=VL_PLOTSIFTDESCRIPTOR(...) returns the handle H to the line drawing representing the descriptors.

The function assumes that the SIFT descriptors use the standard configuration of 4x4 spatial bins and 8 orientations bins. The following parameters can be used to change this:

NumSpatialBins 4

  Number of spatial bins in both spatial directions X and Y.

NumOrientationBins 8

  Number of orientation bis.

MagnificationFactor 3

  Magnification factor. The width of one bin is equal to the scale of the keypoint F multiplied by this factor.

See also: VL_SIFT(), VL_PLOTFRAME(), VL_HELP().