avcodec/wavpack: fix () in macros

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/wavpack.c

@@ -83,7 +83,7 @@ typedef struct WavpackContext {
     int ch_offset;
 } WavpackContext;
 
-#define LEVEL_DECAY(a)  ((a + 0x80) >> 8)
+#define LEVEL_DECAY(a)  (((a) + 0x80) >> 8)
 
 static av_always_inline int get_tail(GetBitContext *gb, int k)
 {

libavcodec/wavpack.h

@@ -99,8 +99,8 @@ typedef struct WvChannel {
 
 // macros for manipulating median values
 #define GET_MED(n) ((c->median[n] >> 4) + 1)
-#define DEC_MED(n) c->median[n] -= ((c->median[n] + (128 >> n) - 2) / (128 >> n)) * 2
-#define INC_MED(n) c->median[n] += ((c->median[n] + (128 >> n)    ) / (128 >> n)) * 5
+#define DEC_MED(n) c->median[n] -= ((c->median[n] + (128 >> (n)) - 2) / (128 >> (n))) * 2
+#define INC_MED(n) c->median[n] += ((c->median[n] + (128 >> (n))    ) / (128 >> (n))) * 5
 
 // macros for applying weight
 #define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \