Peaks which are too short may have been generated by clicking and are discarded. You can sort the list according to the different columns by clicking on them. Please note that you can then change the scope value according to the current scope thus..
At each next octave, Frse resolution of the images is halved to save computations. The images composing the Gaussian and DoG scale space can then be arranged as in the following figure:. Notice that the scale level index s varies in a slightly redundant set. Once extracted, local extrema are quadratically interpolated this is very important especially at the lower resolution scales in order to have accurate keypoint localization at the full resolution.
Finally, they are filtered to eliminate low-contrast responses or responses close to edges and the orientation s are assigned, as explained next.