shithub: libvpx

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Merge "added a last stage rounding for 8x8 inverse dct" into experimental

--- a/vp8/common/idctllm.c

+++ b/vp8/common/idctllm.c

@@ -369,7 +369,7 @@

       ((blk[8 * 0] + 32) >> 6);

     return;

   }

-  x0 = (blk[8 * 0] << 8) + 8192;

+  x0 = (blk[8 * 0] << 8) + 16384;

   /* first stage */

   x8 = W7 * (x4 + x5) + 4;

@@ -399,14 +399,14 @@

   x4 = (181 * (x4 - x5) + 128) >> 8;

   /* fourth stage */

-  blk[8 * 0] = (x7 + x1) >> 14;

-  blk[8 * 1] = (x3 + x2) >> 14;

-  blk[8 * 2] = (x0 + x4) >> 14;

-  blk[8 * 3] = (x8 + x6) >> 14;

-  blk[8 * 4] = (x8 - x6) >> 14;

-  blk[8 * 5] = (x0 - x4) >> 14;

-  blk[8 * 6] = (x3 - x2) >> 14;

-  blk[8 * 7] = (x7 - x1) >> 14;

+  blk[8 * 0] = (x7 + x1 ) >> 15;

+  blk[8 * 1] = (x3 + x2 ) >> 15;

+  blk[8 * 2] = (x0 + x4 ) >> 15;

+  blk[8 * 3] = (x8 + x6 ) >> 15;

+  blk[8 * 4] = (x8 - x6 ) >> 15;

+  blk[8 * 5] = (x0 - x4 ) >> 15;

+  blk[8 * 6] = (x3 - x2 ) >> 15;

+  blk[8 * 7] = (x7 - x1 ) >> 15;

 }

 #define TX_DIM 8

@@ -434,7 +434,7 @@

     {

         for (j = 0; j < TX_DIM; j++)

         {

-             block[i*shortpitch+j]  = X[i * TX_DIM + j]>>1;

+             block[i*shortpitch+j]  = X[i * TX_DIM + j];

         }

     }

 }