commit afe7c5fd7a9073a58e0b24069084100aecbf4735
author Debargha Mukherjee <debargha@google.com> Thu Jun 22 13:47:23 2017 -0700
committer Debargha Mukherjee <debargha@google.com> Fri Jun 23 13:36:49 2017 +0000
tree 29cdc26659a164c2cf2fc0aec99153f63c6a2ef4
parent d598f04df2d8d088f0840f6840dd86c7a7f5beb2

Do not find transformation for very few points

Adds check to make sure that find transformation functions are
never called for 0 points.

Change-Id: I2d7cf40aace535b1d708d6189aea9c1e0f7c281b

av1/encoder/ransac.c

diff --git a/av1/encoder/ransac.c b/av1/encoder/ransac.c
index ce6ae78..c6e3675 100644
--- a/av1/encoder/ransac.c
+++ b/av1/encoder/ransac.c
@@ -139,7 +139,8 @@
   double msqe = 0;
   double scale;
   int i;
-  if (n <= 0) return;
+
+  assert(n > 0);
   for (i = 0; i < n; ++i, p += 2) {
     mean[0] += p[0];
     mean[1] += p[1];
@@ -822,13 +823,15 @@
 
   // Recompute the motions using only the inliers.
   for (i = 0; i < num_desired_motions; ++i) {
-    copy_points_at_indices(points1, corners1, motions[i].inlier_indices,
-                           motions[i].num_inliers);
-    copy_points_at_indices(points2, corners2, motions[i].inlier_indices,
-                           motions[i].num_inliers);
+    if (motions[i].num_inliers >= minpts) {
+      copy_points_at_indices(points1, corners1, motions[i].inlier_indices,
+                             motions[i].num_inliers);
+      copy_points_at_indices(points2, corners2, motions[i].inlier_indices,
+                             motions[i].num_inliers);
 
-    find_transformation(motions[i].num_inliers, points1, points2,
-                        params_by_motion + (MAX_PARAMDIM - 1) * i);
+      find_transformation(motions[i].num_inliers, points1, points2,
+                          params_by_motion + (MAX_PARAMDIM - 1) * i);
+    }
     num_inliers_by_motion[i] = motions[i].num_inliers;
   }