[FFmpeg-devel] [PATCH] Dolby Digital dynamic range compression (drc_scale) is now 0 by default

[Wiebe Cazemier]

Signed-off-by: Wiebe Cazemier <wiebe at halfgaar.net>
---
 Changelog                 | 1 +
 doc/decoders.texi         | 2 +-
 libavcodec/ac3dec_fixed.c | 2 +-
 libavcodec/ac3dec_float.c | 2 +-
 libavutil/version.h       | 2 +-
 5 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/Changelog b/Changelog
index 109a1b8..0bd9875 100644
--- a/Changelog
+++ b/Changelog
@@ -11,6 +11,7 @@ version <next>:
 - nvenc H265 encoder
 - Detelecine filter
 - Intel QSV-accelerated H.264 encoding
+- Dolby Digital dynamic range compression disabled by default
 
 
 version 2.6:
diff --git a/doc/decoders.texi b/doc/decoders.texi
index 01fca9f..ba78a31 100644
--- a/doc/decoders.texi
+++ b/doc/decoders.texi
@@ -72,7 +72,7 @@ from the AC-3 stream. This factor is applied exponentially.
 There are 3 notable scale factor ranges:
 @table @option
 @item drc_scale == 0
-DRC disabled. Produces full range audio.
+DRC disabled. Produces full range audio. Default value.
 @item 0 < drc_scale <= 1
 DRC enabled.  Applies a fraction of the stream DRC value.
 Audio reproduction is between full range and full compression.
diff --git a/libavcodec/ac3dec_fixed.c b/libavcodec/ac3dec_fixed.c
index b4beee6..e3c8ce8 100644
--- a/libavcodec/ac3dec_fixed.c
+++ b/libavcodec/ac3dec_fixed.c
@@ -168,7 +168,7 @@ static void ac3_downmix_c_fixed16(int16_t **samples, int16_t (*matrix)[2],
 #include "ac3dec.c"
 
 static const AVOption options[] = {
-    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
+    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 0.0}, 0.0, 6.0, PAR },
     { "heavy_compr", "heavy dynamic range compression enabled", OFFSET(heavy_compression), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, PAR },
     { NULL},
 };
diff --git a/libavcodec/ac3dec_float.c b/libavcodec/ac3dec_float.c
index d74a0df..5c45c49 100644
--- a/libavcodec/ac3dec_float.c
+++ b/libavcodec/ac3dec_float.c
@@ -32,7 +32,7 @@
 #include "ac3dec.c"
 
 static const AVOption options[] = {
-    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
+    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 0.0}, 0.0, 6.0, PAR },
     { "heavy_compr", "heavy dynamic range compression enabled", OFFSET(heavy_compression), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, PAR },
     { "target_level", "target level in -dBFS (0 not applied)", OFFSET(target_level), AV_OPT_TYPE_INT, {.i64 = 0 }, -31, 0, PAR },
 
diff --git a/libavutil/version.h b/libavutil/version.h
index 897384a..0d8c065 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -57,7 +57,7 @@
 
 #define LIBAVUTIL_VERSION_MAJOR  54
 #define LIBAVUTIL_VERSION_MINOR  20
-#define LIBAVUTIL_VERSION_MICRO 101
+#define LIBAVUTIL_VERSION_MICRO 102
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \
-- 
1.9.1