[FFmpeg-cvslog] aacenc_tns: use 4 bits for short windows

[Rostislav Pehlivanov]

ffmpeg | branch: master | Rostislav Pehlivanov <atomnuker at gmail.com> | Tue Dec  8 13:21:41 2015 +0000| [6e5dbe7267fc5790ff48225623be2ed9abd575c9] | committer: Rostislav Pehlivanov

aacenc_tns: use 4 bits for short windows

With only 7 coefficients per short window at most the extra precision
makes a difference and seems to reduce crackling and stddev even
further.

Signed-off-by: Rostislav Pehlivanov <atomnuker at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6e5dbe7267fc5790ff48225623be2ed9abd575c9
---

 libavcodec/aacenc_tns.c |    2 +-
 tests/fate/aac.mak      |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/aacenc_tns.c b/libavcodec/aacenc_tns.c
index 84f5d09..9ac9ed9 100644
--- a/libavcodec/aacenc_tns.c
+++ b/libavcodec/aacenc_tns.c
@@ -35,7 +35,7 @@
 #define TNS_Q_BITS 4
 
 /* Coefficient resolution in short windows */
-#define TNS_Q_BITS_IS8 3
+#define TNS_Q_BITS_IS8 4
 
 /* We really need the bits we save here elsewhere */
 #define TNS_ENABLE_COEF_COMPRESSION
diff --git a/tests/fate/aac.mak b/tests/fate/aac.mak
index d658751..816fbf0 100644
--- a/tests/fate/aac.mak
+++ b/tests/fate/aac.mak
@@ -182,7 +182,7 @@ fate-aac-tns-encode: CMD = enc_dec_pcm adts wav s16le $(TARGET_SAMPLES)/audio-re
 fate-aac-tns-encode: CMP = stddev
 fate-aac-tns-encode: REF = $(SAMPLES)/audio-reference/luckynight_2ch_44kHz_s16.wav
 fate-aac-tns-encode: CMP_SHIFT = -4096
-fate-aac-tns-encode: CMP_TARGET = 818
+fate-aac-tns-encode: CMP_TARGET = 817
 fate-aac-tns-encode: FUZZ = 6
 fate-aac-tns-encode: SIZE_TOLERANCE = 3560