adjust sad per bit constants

While investigating the effect of DC values on SAD and SSE in motion
estimation, a side finding indicates the two table of constants need
be adjusted. The adjustment was done by multiplying old constants by
90% with rounding. Also absorb the 1/2 scaling constant into the two
tables. Refer to change Ifa285c3e for background of the 1/2 factor.

Cif set test showed a very small gain on all metric.

Change-Id: I04333527a823371175dd46cb04a817e5b9a8b752

diff --git a/vp8/encoder/rdopt.c b/vp8/encoder/rdopt.c
index d4d6cd7c7559f677bc2da8801809bb9ff26931f1..124de478cc17a2a033d1ae552733d33535626b68 100644 (file)
--- a/vp8/encoder/rdopt.c
+++ b/vp8/encoder/rdopt.c
@@ -155,51 +155,50 @@ static int rd_iifactor [ 32 ] =  {    4,   4,   3,   2,   1,   0,   0,   0,
                                       0,   0,   0,   0,   0,   0,   0,   0,
                                  };
 
-
 /* values are now correlated to quantizer */
 static int sad_per_bit16lut[QINDEX_RANGE] =
 {
+    2,  2,  2,  2,  2,  2,  2,  2,
+    2,  2,  2,  2,  2,  2,  2,  2,
+    3,  3,  3,  3,  3,  3,  3,  3,
+    3,  3,  3,  3,  3,  3,  4,  4,
+    4,  4,  4,  4,  4,  4,  4,  4,
+    4,  4,  5,  5,  5,  5,  5,  5,
     5,  5,  5,  5,  5,  5,  6,  6,
-    6,  6,  6,  6,  6,  7,  7,  7,
-    7,  7,  7,  7,  8,  8,  8,  8,
-    8,  8,  8,  8,  8,  8,  9,  9,
-    9,  9,  9,  9, 10, 10, 10, 10,
-    10, 10, 11, 11, 11, 11, 11, 11,
-    12, 12, 12, 12, 12, 12, 12, 13,
-    13, 13, 13, 13, 13, 14, 14, 14,
-    14, 14, 15, 15, 15, 15, 15, 15,
-    16, 16, 16, 16, 16, 16, 17, 17,
-    17, 17, 17, 17, 17, 18, 18, 18,
-    18, 18, 19, 19, 19, 19, 19, 19,
-    20, 20, 20, 21, 21, 21, 21, 22,
-    22, 22, 23, 23, 23, 24, 24, 24,
-    25, 25, 26, 26, 27, 27, 27, 28,
-    28, 28, 29, 29, 30, 30, 31, 31
+    6,  6,  6,  6,  6,  6,  6,  6,
+    6,  6,  7,  7,  7,  7,  7,  7,
+    7,  7,  7,  7,  7,  7,  8,  8,
+    8,  8,  8,  8,  8,  8,  8,  8,
+    8,  8,  9,  9,  9,  9,  9,  9,
+    9,  9,  9,  9,  9,  9,  10, 10,
+    10, 10, 10, 10, 10, 10, 11, 11,
+    11, 11, 11, 11, 12, 12, 12, 12,
+    12, 12, 13, 13, 13, 13, 14, 14
 };
 static int sad_per_bit4lut[QINDEX_RANGE] =
 {
-    5,  5,  5,  5,  5,  5,  7,  7,
+    2,  2,  2,  2,  2,  2,  3,  3,
+    3,  3,  3,  3,  3,  3,  3,  3,
+    3,  3,  3,  3,  4,  4,  4,  4,
+    4,  4,  4,  4,  4,  4,  5,  5,
+    5,  5,  5,  5,  6,  6,  6,  6,
+    6,  6,  6,  6,  6,  6,  6,  6,
+    7,  7,  7,  7,  7,  7,  7,  7,
     7,  7,  7,  7,  7,  8,  8,  8,
-    8,  8,  8,  8,  10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 11, 11,
-    11, 11, 11, 11, 13, 13, 13, 13,
-    13, 13, 14, 14, 14, 14, 14, 14,
-    16, 16, 16, 16, 16, 16, 16, 17,
-    17, 17, 17, 17, 17, 19, 19, 19,
-    19, 19, 20, 20, 20, 20, 20, 20,
-    22, 22, 22, 22, 22, 22, 23, 23,
-    23, 23, 23, 23, 23, 25, 25, 25,
-    25, 25, 26, 26, 26, 26, 26, 26,
-    28, 28, 28, 29, 29, 29, 29, 31,
-    31, 31, 32, 32, 32, 34, 34, 34,
-    35, 35, 37, 37, 38, 38, 38, 40,
-    40, 40, 41, 41, 43, 43, 44, 44,
+    8,  8,  9,  9,  9,  9,  9,  9,
+    10, 10, 10, 10, 10, 10, 10, 10,
+    11, 11, 11, 11, 11, 11, 11, 11,
+    12, 12, 12, 12, 12, 12, 12, 12,
+    13, 13, 13, 13, 13, 13, 13, 14,
+    14, 14, 14, 14, 15, 15, 15, 15,
+    16, 16, 16, 16, 17, 17, 17, 18,
+    18, 18, 19, 19, 19, 20, 20, 20,
 };
 
 void vp8cx_initialize_me_consts(VP8_COMP *cpi, int QIndex)
 {
-    cpi->mb.sadperbit16 =  sad_per_bit16lut[QIndex]/2;
-    cpi->mb.sadperbit4  =  sad_per_bit4lut[QIndex]/2;
+    cpi->mb.sadperbit16 =  sad_per_bit16lut[QIndex];
+    cpi->mb.sadperbit4  =  sad_per_bit4lut[QIndex];
 }
 
 void vp8_initialize_rd_consts(VP8_COMP *cpi, int Qvalue)