summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorClément Bœsch <ubitux@gmail.com>2012-12-18 21:44:51 +0100
committerClément Bœsch <ubitux@gmail.com>2012-12-19 03:13:26 +0100
commit3bdd70fc661feaf915ae438e05f66cce75334673 (patch)
tree43fe01862cc4b47b4b008d75aae067d7e429d35a
parent63e1fc25884fe7cf3f66a8b99602ca98a47fb763 (diff)
lavfi/gradfun: reduce up limit for threshold.
This will prevent an overflow in the SSSE3 and MMX filter_line code: delta is expressed as an u16 being shifted by 2 to the left. If it overflows, having a strength not above 64 will make sure that m is set to 0 (making the m*m*delta >> 14 expression void). A value above 64 should not make any sense unless gradfun is used as a blur filter.
-rw-r--r--doc/filters.texi2
-rw-r--r--libavfilter/version.h2
-rw-r--r--libavfilter/vf_gradfun.c2
3 files changed, 3 insertions, 3 deletions
diff --git a/doc/filters.texi b/doc/filters.texi
index 827dcf3753..2f50d65bb8 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2670,7 +2670,7 @@ The filter takes two optional parameters, separated by ':':
@var{strength} is the maximum amount by which the filter will change
any one pixel. Also the threshold for detecting nearly flat
-regions. Acceptable values range from .51 to 255, default value is
+regions. Acceptable values range from .51 to 64, default value is
1.2, out-of-range values will be clipped to the valid range.
@var{radius} is the neighborhood to fit the gradient to. A larger
diff --git a/libavfilter/version.h b/libavfilter/version.h
index 048cacec3e..26b66457c5 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
#define LIBAVFILTER_VERSION_MAJOR 3
#define LIBAVFILTER_VERSION_MINOR 28
-#define LIBAVFILTER_VERSION_MICRO 100
+#define LIBAVFILTER_VERSION_MICRO 101
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vf_gradfun.c b/libavfilter/vf_gradfun.c
index 9255f614a2..6319bf7d28 100644
--- a/libavfilter/vf_gradfun.c
+++ b/libavfilter/vf_gradfun.c
@@ -128,7 +128,7 @@ static av_cold int init(AVFilterContext *ctx, const char *args)
if (args)
sscanf(args, "%f:%d", &thresh, &radius);
- thresh = av_clipf(thresh, 0.51, 255);
+ thresh = av_clipf(thresh, 0.51, 64);
gf->thresh = (1 << 15) / thresh;
gf->radius = av_clip((radius + 1) & ~1, 4, 32);