ENH: optimizing tiepoint search.

Common/geometry.py

@@ -116,7 +116,7 @@ def compute_displacement_with_masks(_src: otb.Application, _tgt: otb.Application
     mask = np.all((mask, ref_mask), axis=0).astype(int)
     H, W = mask.shape
     ratio = np.sum(mask)/(H*W) #scale number of bins based on coverage ratio
-    cnt, cov, cov_ext = get_patch_centers(mask, geobin_size, int(ratio*num_geobins), margin=margin)
+    cnt, cov, cov_ext = get_patch_centers(mask, geobin_size, max(1,int(ratio*num_geobins)), margin=margin)
     _src_msk.FreeRessources()
     _tgt_msk.FreeRessources()