patches extracted question

[DIVE128]

After reading the description about Patch Extraction Method.There'are some question:
1.'multiple detections with ellipse overlap greater than 50% 'means two keypoint’region or more.
2. aside from the reference,are the detections from other image calculated by reference and the parameters form H_ref_X or calculated like the refercence and match them then give the same label?
could you put codes about Patch Extracting? thanks a lot