Normalize quantizer's zero bin and rounding factors

This patch changes a few numbers in the two constant arrays
for quantizer's zerobin and rounding factors, in general to
make the sum of the two factors for any Q to be 128.  While
it might be beneficial to calibrate the two arrays for best
quantizer performance, it is not the purpose of this patch.
Normalizing the two arrays will enable quick optimization
of the current faster quantizer, i.e .zerobin check can be
removed.

Change-Id: If9abfd7929bf4b8e9ecd64a79d817c6728c820bd

diff --git a/vp8/encoder/encodeframe.c b/vp8/encoder/encodeframe.c
index 4e4483e..905ef88 100644 (file)
--- a/vp8/encoder/encodeframe.c
+++ b/vp8/encoder/encodeframe.c
@@ -60,10 +60,9 @@ unsigned int uv_modes[4]  = {0, 0, 0, 0};
 unsigned int b_modes[14]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 #endif
 
-// The first four entries are dummy values
 static const int qrounding_factors[129] =
 {
-    56, 56, 56, 56, 56, 56, 56, 56,
+    56, 56, 56, 56, 48, 48, 56, 56,
     48, 48, 48, 48, 48, 48, 48, 48,
     48, 48, 48, 48, 48, 48, 48, 48,
     48, 48, 48, 48, 48, 48, 48, 48,
@@ -84,7 +83,7 @@ static const int qrounding_factors[129] =
 
 static const int qzbin_factors[129] =
 {
-    64, 64, 64, 64, 80, 80, 80, 80,
+    72, 72, 72, 72, 80, 80, 72, 72,
     80, 80, 80, 80, 80, 80, 80, 80,
     80, 80, 80, 80, 80, 80, 80, 80,
     80, 80, 80, 80, 80, 80, 80, 80,