Bug fix in motion vector limit calculation

Motion vector limits are calculated using right shifts, which
could give wrong results for negative numbers. James Berry's
test on one clip showed encoder produced some artifacts. This
change fixed that.

Change-Id: I035fc02280b10455b7f6eb388f7c2e33b796b018

diff --git a/vp8/encoder/mcomp.c b/vp8/encoder/mcomp.c
index 41694887085e58be82f36c7960b5004feee93c14..6f314a386e1000e51d6353ced8f3ab7a7a567043 100644 (file)
--- a/vp8/encoder/mcomp.c
+++ b/vp8/encoder/mcomp.c
@@ -286,8 +286,8 @@ int vp8_find_best_sub_pixel_step_iteratively(MACROBLOCK *x, BLOCK *b, BLOCKD *d,
     bestmv->as_mv.row = br << 1;
     bestmv->as_mv.col = bc << 1;
 
-    if ((abs(bestmv->as_mv.col - ref_mv->as_mv.col) > MAX_FULL_PEL_VAL) ||
-        (abs(bestmv->as_mv.row - ref_mv->as_mv.row) > MAX_FULL_PEL_VAL))
+    if ((abs(bestmv->as_mv.col - ref_mv->as_mv.col) > (MAX_FULL_PEL_VAL<<3)) ||
+        (abs(bestmv->as_mv.row - ref_mv->as_mv.row) > (MAX_FULL_PEL_VAL<<3)))
         return INT_MAX;
 
     return besterr;

diff --git a/vp8/encoder/mcomp.h b/vp8/encoder/mcomp.h
index 44ed055db9793f9209468923652fb6d80bc5b3b9..416c4d5eb6a19b78c5424730d508728e75b40308 100644 (file)
--- a/vp8/encoder/mcomp.h
+++ b/vp8/encoder/mcomp.h
@@ -22,7 +22,7 @@ extern void accum_mv_refs(MB_PREDICTION_MODE, const int near_mv_ref_cts[4]);
 
 
 #define MAX_MVSEARCH_STEPS 8                                    // The maximum number of steps in a step search given the largest allowed initial step
-#define MAX_FULL_PEL_VAL ((1 << (MAX_MVSEARCH_STEPS+3)) - 8)    // Max full pel mv specified in 1/8 pel units
+#define MAX_FULL_PEL_VAL ((1 << (MAX_MVSEARCH_STEPS)) - 1)      // Max full pel mv specified in 1 pel units
 #define MAX_FIRST_STEP (1 << (MAX_MVSEARCH_STEPS-1))            // Maximum size of the first step in full pel units
 
 extern void print_mode_context(void);

diff --git a/vp8/encoder/pickinter.c b/vp8/encoder/pickinter.c
index b60d2419fc75969933190054480385a3e30ceab3..6c73511a9bd4ab78ffc10729292732fc503b5faa 100644 (file)
--- a/vp8/encoder/pickinter.c
+++ b/vp8/encoder/pickinter.c
@@ -588,10 +588,10 @@ void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
 
             /* adjust mvp to make sure it is within MV range */
             vp8_clamp_mv(&mvp,
-                         best_ref_mv.as_mv.col - MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.col + MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.row - MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.row + MAX_FULL_PEL_VAL);
+                         best_ref_mv.as_mv.col - (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.col + (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.row - (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.row + (MAX_FULL_PEL_VAL<<3));
         }
 
         switch (this_mode)
@@ -681,10 +681,14 @@ void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,
                 mvp.as_int = best_ref_mv.as_int;
             }
 
-            col_min = (best_ref_mv.as_mv.col - MAX_FULL_PEL_VAL) >>3;
-            col_max = (best_ref_mv.as_mv.col + MAX_FULL_PEL_VAL) >>3;
-            row_min = (best_ref_mv.as_mv.row - MAX_FULL_PEL_VAL) >>3;
-            row_max = (best_ref_mv.as_mv.row + MAX_FULL_PEL_VAL) >>3;
+            col_min = (best_ref_mv.as_mv.col < 0)?(-((abs(best_ref_mv.as_mv.col))>>3) - MAX_FULL_PEL_VAL)
+                                                 :((best_ref_mv.as_mv.col>>3) - MAX_FULL_PEL_VAL);
+            col_max = (best_ref_mv.as_mv.col < 0)?(-((abs(best_ref_mv.as_mv.col))>>3) + MAX_FULL_PEL_VAL)
+                                                 :((best_ref_mv.as_mv.col>>3) + MAX_FULL_PEL_VAL);
+            row_min = (best_ref_mv.as_mv.row < 0)?(-((abs(best_ref_mv.as_mv.row))>>3) - MAX_FULL_PEL_VAL)
+                                                 :((best_ref_mv.as_mv.row>>3) - MAX_FULL_PEL_VAL);
+            row_max = (best_ref_mv.as_mv.row < 0)?(-((abs(best_ref_mv.as_mv.row))>>3) + MAX_FULL_PEL_VAL)
+                                                 :((best_ref_mv.as_mv.row>>3) + MAX_FULL_PEL_VAL);
 
             // Get intersection of UMV window and valid MV window to reduce # of checks in diamond search.
             if (x->mv_col_min < col_min )

diff --git a/vp8/encoder/rdopt.c b/vp8/encoder/rdopt.c
index e0359057a1da2d7628d022eda52047bbba9a3e2f..fa5bb079b0706e7aeeec4df7a5ac53a229c3bd5a 100644 (file)
--- a/vp8/encoder/rdopt.c
+++ b/vp8/encoder/rdopt.c
@@ -1330,10 +1330,14 @@ static int vp8_rd_pick_best_mbsegmentation(VP8_COMP *cpi, MACROBLOCK *x,
 
         if (bsi.segment_rd < best_rd)
         {
-            int col_min = (best_ref_mv->as_mv.col - MAX_FULL_PEL_VAL) >>3;
-            int col_max = (best_ref_mv->as_mv.col + MAX_FULL_PEL_VAL) >>3;
-            int row_min = (best_ref_mv->as_mv.row - MAX_FULL_PEL_VAL) >>3;
-            int row_max = (best_ref_mv->as_mv.row + MAX_FULL_PEL_VAL) >>3;
+            int col_min = (best_ref_mv->as_mv.col < 0)?(-((abs(best_ref_mv->as_mv.col))>>3) - MAX_FULL_PEL_VAL)
+                                                      :((best_ref_mv->as_mv.col>>3) - MAX_FULL_PEL_VAL);
+            int col_max = (best_ref_mv->as_mv.col < 0)?(-((abs(best_ref_mv->as_mv.col))>>3) + MAX_FULL_PEL_VAL)
+                                                      :((best_ref_mv->as_mv.col>>3) + MAX_FULL_PEL_VAL);
+            int row_min = (best_ref_mv->as_mv.row < 0)?(-((abs(best_ref_mv->as_mv.row))>>3) - MAX_FULL_PEL_VAL)
+                                                      :((best_ref_mv->as_mv.row>>3) - MAX_FULL_PEL_VAL);
+            int row_max = (best_ref_mv->as_mv.row < 0)?(-((abs(best_ref_mv->as_mv.row))>>3) + MAX_FULL_PEL_VAL)
+                                                      :((best_ref_mv->as_mv.row>>3) + MAX_FULL_PEL_VAL);
 
             int tmp_col_min = x->mv_col_min;
             int tmp_col_max = x->mv_col_max;
@@ -1876,10 +1880,10 @@ void vp8_rd_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset, int
 
             /* adjust mvp to make sure it is within MV range */
             vp8_clamp_mv(&mvp,
-                         best_ref_mv.as_mv.col - MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.col + MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.row - MAX_FULL_PEL_VAL,
-                         best_ref_mv.as_mv.row + MAX_FULL_PEL_VAL);
+                         best_ref_mv.as_mv.col - (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.col + (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.row - (MAX_FULL_PEL_VAL<<3),
+                         best_ref_mv.as_mv.row + (MAX_FULL_PEL_VAL<<3));
         }
 
         // Check to see if the testing frequency for this mode is at its max
@@ -2011,10 +2015,14 @@ void vp8_rd_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset, int
 
             int sadpb = x->sadperbit16;
 
-            int col_min = (best_ref_mv.as_mv.col - MAX_FULL_PEL_VAL) >>3;
-            int col_max = (best_ref_mv.as_mv.col + MAX_FULL_PEL_VAL) >>3;
-            int row_min = (best_ref_mv.as_mv.row - MAX_FULL_PEL_VAL) >>3;
-            int row_max = (best_ref_mv.as_mv.row + MAX_FULL_PEL_VAL) >>3;
+            int col_min = (best_ref_mv.as_mv.col < 0)?(-((abs(best_ref_mv.as_mv.col))>>3) - MAX_FULL_PEL_VAL)
+                                                     :((best_ref_mv.as_mv.col>>3) - MAX_FULL_PEL_VAL);
+            int col_max = (best_ref_mv.as_mv.col < 0)?(-((abs(best_ref_mv.as_mv.col))>>3) + MAX_FULL_PEL_VAL)
+                                                     :((best_ref_mv.as_mv.col>>3) + MAX_FULL_PEL_VAL);
+            int row_min = (best_ref_mv.as_mv.row < 0)?(-((abs(best_ref_mv.as_mv.row))>>3) - MAX_FULL_PEL_VAL)
+                                                     :((best_ref_mv.as_mv.row>>3) - MAX_FULL_PEL_VAL);
+            int row_max = (best_ref_mv.as_mv.row < 0)?(-((abs(best_ref_mv.as_mv.row))>>3) + MAX_FULL_PEL_VAL)
+                                                     :((best_ref_mv.as_mv.row>>3) + MAX_FULL_PEL_VAL);
 
             int tmp_col_min = x->mv_col_min;
             int tmp_col_max = x->mv_col_max;