Reoptimizing the interpolation filters

Reoptimizes the 8-tap smooth filter.

Results:
derf: +0.101%
yt: +0.157%
hd: +0.791%
stdhd: +0.264%

The next step will be to reoptimize the other two filters.

Change-Id: I3d256a510ad9c7c30c33fae4a70fb43dfc708ed0

diff --git a/vp9/common/vp9_filter.c b/vp9/common/vp9_filter.c
index 434c63e..6c1ea21 100644 (file)
--- a/vp9/common/vp9_filter.c
+++ b/vp9/common/vp9_filter.c
@@ -34,8 +34,9 @@ DECLARE_ALIGNED(256, const int16_t, vp9_bilinear_filters[SUBPEL_SHIFTS][8]) = {
   { 0, 0, 0,   8, 120, 0, 0, 0 }
 };
 
-#define FILTER_ALPHA       0
-#define FILTER_ALPHA_SHARP 1
+#define FILTER_ALPHA        0
+#define FILTER_ALPHA_SHARP  0
+#define FILTER_ALPHA_SMOOTH 50
 DECLARE_ALIGNED(256, const int16_t, vp9_sub_pel_filters_8[SUBPEL_SHIFTS][8])
     = {
 #if FILTER_ALPHA == 0
@@ -81,12 +82,13 @@ DECLARE_ALIGNED(256, const int16_t, vp9_sub_pel_filters_8[SUBPEL_SHIFTS][8])
   { 0,   3,  -9,  27, 118, -13,   3, -1},
   { 0,   2,  -6,  18, 122, -10,   2,  0},
   { 0,   1,  -3,   8, 126,  -5,   1,  0}
+
 #endif  /* FILTER_ALPHA */
 };
 
 DECLARE_ALIGNED(256, const int16_t, vp9_sub_pel_filters_8s[SUBPEL_SHIFTS][8])
     = {
-#if FILTER_ALPHA_SHARP == 1
+#if FILTER_ALPHA_SHARP == 0
   /* dct based filter */
   {0,   0,   0, 128,   0,   0,   0, 0},
   {-1,   3,  -7, 127,   8,  -3,   1, 0},
@@ -105,24 +107,24 @@ DECLARE_ALIGNED(256, const int16_t, vp9_sub_pel_filters_8s[SUBPEL_SHIFTS][8])
   {-1,   3,  -6,  17, 125, -13,   5, -2},
   {0,   1,  -3,   8, 127,  -7,   3, -1}
 
-#elif FILTER_ALPHA_SHARP == 75
-  /* alpha = 0.75 */
-  {0,   0,   0, 128,   0,   0,   0, 0},
-  {-1,   2,  -6, 126,   9,  -3,   2, -1},
-  {-1,   4, -11, 123,  18,  -7,   3, -1},
-  {-2,   6, -16, 119,  28, -10,   5, -2},
-  {-2,   7, -19, 113,  38, -13,   6, -2},
-  {-3,   8, -21, 106,  49, -16,   7, -2},
-  {-3,   9, -22,  99,  59, -19,   8, -3},
-  {-3,   9, -23,  90,  70, -21,   9, -3},
-  {-3,   9, -22,  80,  80, -22,   9, -3},
-  {-3,   9, -21,  70,  90, -23,   9, -3},
-  {-3,   8, -19,  59,  99, -22,   9, -3},
-  {-2,   7, -16,  49, 106, -21,   8, -3},
-  {-2,   6, -13,  38, 113, -19,   7, -2},
-  {-2,   5, -10,  28, 119, -16,   6, -2},
-  {-1,   3,  -7,  18, 123, -11,   4, -1},
-  {-1,   2,  -3,   9, 126,  -6,   2, -1}
+#elif FILTER_ALPHA_SHARP == 80
+  /* alpha = 0.80 */
+  { 0,   0,   0, 128,   0,   0,   0,  0},
+  {-1,   2,  -6, 127,   9,  -4,   2, -1},
+  {-2,   5, -12, 124,  18,  -7,   4, -2},
+  {-2,   7, -16, 119,  28, -11,   5, -2},
+  {-3,   8, -19, 114,  38, -14,   7, -3},
+  {-3,   9, -22, 107,  49, -17,   8, -3},
+  {-4,  10, -23,  99,  60, -20,  10, -4},
+  {-4,  11, -23,  90,  70, -22,  10, -4},
+  {-4,  11, -23,  80,  80, -23,  11, -4},
+  {-4,  10, -22,  70,  90, -23,  11, -4},
+  {-4,  10, -20,  60,  99, -23,  10, -4},
+  {-3,   8, -17,  49, 107, -22,   9, -3},
+  {-3,   7, -14,  38, 114, -19,   8, -3},
+  {-2,   5, -11,  28, 119, -16,   7, -2},
+  {-2,   4,  -7,  18, 124, -12,   5, -2},
+  {-1,   2,  -4,   9, 127,  -6,   2, -1}
 #endif  /* FILTER_ALPHA_SHARP */
 };
 
@@ -130,6 +132,8 @@ DECLARE_ALIGNED(256, const int16_t,
                 vp9_sub_pel_filters_8lp[SUBPEL_SHIFTS][8]) = {
   /* 8-tap lowpass filter */
   /* Hamming window */
+  /* freqmultiplier = 0.625 */
+#if FILTER_ALPHA_SMOOTH == 625
   {-1, -7, 32, 80, 32, -7, -1,  0},
   {-1, -8, 28, 80, 37, -7, -2,  1},
   { 0, -8, 24, 79, 41, -7, -2,  1},
@@ -146,6 +150,26 @@ DECLARE_ALIGNED(256, const int16_t,
   { 1, -3, -5, 45, 78, 20, -8,  0},
   { 1, -2, -7, 41, 79, 24, -8,  0},
   { 1, -2, -7, 37, 80, 28, -8, -1}
+
+#elif FILTER_ALPHA_SMOOTH == 50
+  /* freqmultiplier = 0.5 */
+  {-3,  0, 35, 64, 35,  0, -3, 0},
+  {-3, -1, 32, 64, 38,  1, -3, 0},
+  {-2, -2, 29, 63, 41,  2, -3, 0},
+  {-2, -2, 26, 63, 43,  4, -4, 0},
+  {-2, -3, 24, 62, 46,  5, -4, 0},
+  {-2, -3, 21, 60, 49,  7, -4, 0},
+  {-1, -4, 18, 59, 51,  9, -4, 0},
+  {-1, -4, 16, 57, 53, 12, -4, -1},
+  {-1, -4, 14, 55, 55, 14, -4, -1},
+  {-1, -4, 12, 53, 57, 16, -4, -1},
+  {0, -4,  9, 51, 59, 18, -4, -1},
+  {0, -4,  7, 49, 60, 21, -3, -2},
+  {0, -4,  5, 46, 62, 24, -3, -2},
+  {0, -4,  4, 43, 63, 26, -2, -2},
+  {0, -3,  2, 41, 63, 29, -2, -2},
+  {0, -3,  1, 38, 64, 32, -1, -3}
+#endif
 };
 
 DECLARE_ALIGNED(256, const int16_t, vp9_sub_pel_filters_6[SUBPEL_SHIFTS][8])