ac3enc: Change EXP_DIFF_THRESHOLD to 500.

This patch changes the exponent difference threshold in the exponent
strategy decision function of the AC-3 encoder.  I tested lowering in
increments of 100.  From 1000 down to 500 generally increased in quality
with each step, but 400 was generally much worse.

Signed-off-by: Mans Rullgard <mans@mansr.com>

diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c
index ed7a171..e41a0ae 100644 (file)
--- a/libavcodec/ac3enc.c
+++ b/libavcodec/ac3enc.c
@@ -434,7 +434,7 @@ static void extract_exponents(AC3EncodeContext *s)
  * Exponent Difference Threshold.
  * New exponents are sent if their SAD exceed this number.
  */
-#define EXP_DIFF_THRESHOLD 1000
+#define EXP_DIFF_THRESHOLD 500
 
 
 /**

diff --git a/tests/ref/acodec/ac3_fixed b/tests/ref/acodec/ac3_fixed
index 17159e1..5c75ecd 100644 (file)
--- a/tests/ref/acodec/ac3_fixed
+++ b/tests/ref/acodec/ac3_fixed
@@ -1,2 +1,2 @@
-9823c8f74097eab5d148cf0536ae932e *./tests/data/acodec/ac3.rm
+37e119c644ba0472c079d0e907bf78df *./tests/data/acodec/ac3.rm
 98751 ./tests/data/acodec/ac3.rm

diff --git a/tests/ref/lavf/rm b/tests/ref/lavf/rm
index d9ec51e..c26dd0a 100644 (file)
--- a/tests/ref/lavf/rm
+++ b/tests/ref/lavf/rm
@@ -1,2 +1,2 @@
-e1990def7b195a568340f2c1a89d6587 *./tests/data/lavf/lavf.rm
+b97899ef2812cd1c8851dea550e042e4 *./tests/data/lavf/lavf.rm
 346706 ./tests/data/lavf/lavf.rm