That's why I suggested to always return the masks as well. 

> Am 21.09.2013 um 18:17 schrieb "AnkitAgrawal" <notifications@github.com>:
> 
> In skimage/feature/match.py:
> 
> > +    descriptors2 : (N, P) ndarray
> > +        BRIEF descriptors of size P about N keypoints in the second image.
> > +    threshold : float in range [0, 1]
> > +        Maximum allowable hamming distance between descriptors of two keypoints
> > +        in separate images to be regarded as a match.
> > +    cross_check : bool
> > +        Cross check if True.
> > +    return_mask : bool
> > +        Return index masks mask1 and mask2 for matched keypoints from
> > +        keypoints1 and keypoints2 respectively.
> > +
> > +    Returns
> > +    -------
> > +    match_keypoints_pairs : (Q, 2, 2) ndarray
> > +        Location of Q matched keypoint pairs from two images.
> > +    mask1 : (Q,) ndarray
> @ahojnnes : I get your point, but in this case, it is important enough to return the matched keypoints directly and also important to have the mask if the user wants to visualize them by scale i.e. keypoint ring proportional to its scale.
> 
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