Add av_clip_int8(), used in the upcoming VP8 decoder.

Originally committed as revision 23713 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 11 insertions, 0 deletions

diff --git a/libavutil/common.h b/libavutil/common.h
index ba67b4a559..ee4417558c 100644
--- a/libavutil/common.h
+++ b/libavutil/common.h
@@ -123,6 +123,17 @@ static inline av_const uint8_t av_clip_uint8(int a)
 }
 
 /**
+ * Clips a signed integer value into the -128,127 range.
+ * @param a value to clip
+ * @return clipped value
+ */
+static inline av_const int8_t av_clip_int8(int a)
+{
+    if ((a+0x80) & ~0xFF) return (a>>31) ^ 0x7F;
+    else                  return a;
+}
+
+/**
  * Clips a signed integer value into the 0-65535 range.
  * @param a value to clip
  * @return clipped value