diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 8d8b6356045f945f76edee1b0e352c6e4992c909..9641a882f22d38b37361e2e3532500bb7d75846e 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -921,7 +921,7 @@ typedef struct AVCodecContext {
 
     /* audio only */
     int sample_rate; ///< samples per second
-    int channels;
+    int channels;    ///< number of audio channels
 
     /**
      * audio sample format