diff --git a/libavcodec/put_bits.h b/libavcodec/put_bits.h
index 3bddd44ac0..32b11f6445 100644
--- a/libavcodec/put_bits.h
+++ b/libavcodec/put_bits.h
@@ -259,7 +259,10 @@ static inline void put_sbits(PutBitContext *pb, int bits, int32_t val)
     put_bits(pb, bits, val & ((1<<bits)-1));
 }
 
-
+/**
+ * Returns the pointer to the byte where the bitstream writer will put
+ * the next bit.
+ */
 static inline uint8_t* pbBufPtr(PutBitContext *s)
 {
 #ifdef ALT_BITSTREAM_WRITER