shithub: dav1d

Info  •  Files  •  Log  •  Branches

Remove dav1d_sgr_one_by_x

Since n equals either 25 or 9, the dav1d_sgr_one_by_x table can be
replaced with a ternary operation.

--- a/src/looprestoration_tmpl.c

+++ b/src/looprestoration_tmpl.c

@@ -412,6 +412,8 @@

                               const ptrdiff_t src_stride, const int w,

                               const int h, const int n, const int s)

 {

+    const int sgr_one_by_x = n == 25 ? 164 : 455;

+

     // Selfguided filter is applied to a maximum stripe height of 64 + 3 pixels

     // of padding above and below

     int32_t A_[70 /*(64 + 3 + 3)*/ * REST_UNIT_STRIDE];

@@ -444,7 +446,7 @@

             const int x = dav1d_sgr_x_by_xplus1[imin(z, 255)];

             // This is where we invert A and B, so that B is of size coef.

-            AA[i] = (((1 << 8) - x) * BB[i] * dav1d_sgr_one_by_x[n - 1] + (1 << 11)) >> 12;

+            AA[i] = (((1 << 8) - x) * BB[i] * sgr_one_by_x + (1 << 11)) >> 12;

             BB[i] = x;

         }

         AA += step * REST_UNIT_STRIDE;

--- a/src/tables.c

+++ b/src/tables.c

@@ -523,11 +523,6 @@

   256,

 };

-const int16_t dav1d_sgr_one_by_x[25] = {

-  4096, 2048, 1365, 1024, 819, 683, 585, 512, 455, 410, 372, 341, 315,

-  293,  273,  256,  241,  228, 216, 205, 195, 186, 178, 171, 164,

-};

-

 const int8_t ALIGN(dav1d_mc_subpel_filters[5][15][8], 8) = {

     [FILTER_8TAP_REGULAR] = {

         {   0,   1,  -3,  63,   4,  -1,   0,   0 },