Merge "Changes 16 point idct" into experimental

vp9/common/vp9_rtcd_defs.sh

@@ -398,6 +398,10 @@ specialize vp9_short_idct16x16
 prototype void vp9_short_idct10_16x16 "int16_t *input, int16_t *output, int pitch"
 specialize vp9_short_idct10_16x16
 
+prototype void vp9_short_idct1_16x16 "int16_t *input, int16_t *output"
+specialize vp9_short_idct1_16x16
+
+
 prototype void vp9_short_idct32x32 "int16_t *input, int16_t *output, int pitch"
 specialize vp9_short_idct32x32
 

vp9/decoder/vp9_dequantize.c

@@ -300,14 +300,11 @@ void vp9_dequant_idct_add_16x16_c(int16_t *input, const int16_t *dq,
     vp9_copy_mem16x16(pred, pitch, dest, stride);
   } else if (eob == 1) {
     /* DC only DCT coefficient. */
+    int16_t in = input[0] * dq[0];
     int16_t out;
-
     /* Note: the idct1 will need to be modified accordingly whenever
      * vp9_short_idct16x16_c() is modified. */
-    out = (input[0] * dq[0] + 2) >> 2;
-    out = (out + 2) >> 2;
-    out = (out + 4) >> 3;
-
+    vp9_short_idct1_16x16_c(&in, &out);
     input[0] = 0;
 
     add_constant_residual(out, pred, pitch, dest, stride, 16, 16);