Fig. 3
From: Structure from motion using dense CNN features with keypoint relocalization
Keypoint relocalization. a A keypoint on a sparser level is relocalized using a map computed from descriptors’ L2 norm on an lower level which has higher spatial resolution. It is reassigned at the position on the lower level which has the largest value in the corresponding K×K neighborhood. By repeating this, the relocalized keypoint position in conv1_2 has the accuracy as in the input image pixels. b The green dots show the extracted conv3 features points (top) and the result of our keypoint relocalization (bottom)