Remove redundant mv_pred use for sub8x8 blocks

The sub8x8 blocks has its own motion vector reference scheme. The
mv_pred is only used blocks of sizes 8x8 and above, to find the
starting point for motion search.

This change does not change any coding behavior. It makes the
encoding process slightly faster. (0.5% speed-up for local test on
speed 1.)

Change-Id: I746ee6ef0eac19aa3621be014afa12be8d82cbb9

diff --git a/vp9/encoder/vp9_rdopt.c b/vp9/encoder/vp9_rdopt.c
index 470379c47fb0a75355b78f4e4968d934cf1743ba..3ef3eeeebf4ae3f196b161d9d36b897c4b3ab104 100644 (file)
--- a/vp9/encoder/vp9_rdopt.c
+++ b/vp9/encoder/vp9_rdopt.c
@@ -2296,7 +2296,7 @@ static void setup_buffer_inter(VP9_COMP *cpi, MACROBLOCK *x,
   // Further refinement that is encode side only to test the top few candidates
   // in full and choose the best as the centre point for subsequent searches.
   // The current implementation doesn't support scaling.
-  if (!vp9_is_scaled(&scale[frame_type]))
+  if (!vp9_is_scaled(&scale[frame_type]) && block_size >= BLOCK_8X8)
     mv_pred(cpi, x, yv12_mb[frame_type][0].buf, yv12->y_stride,
             frame_type, block_size);
 }