Feature matching of images without corners
I have referred to Stage I.D of this tutorial. Hope this helps.
http://www.robots.ox.ac.uk/~vgg/practicals/instance-recognition/index.html#stage-id-improving-sift-matching-using-a-geometric-transformation

When the features have scale and orientation assigned (e.g. SIFT features have these properties), you can compute similarity transform between each corresponding feature pair. The similarity transform has 4 parameters: Tx, Ty - translation, R - rotation and S - scale.

The tentative correspondences are then filtered using RANSAC-like algorithm such that only correspondences consistent with common similarity transform (up to a predefined threshold) are used.