avcodec: clarify documentation of avcodec_copy_context()

Following this is not strictly needed but safes some malloc+free

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

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index e4c97cca5d1b3251888cb011a3aad1c7d65f3d73..070ce7a12d8cdfe5af19dbdd3da588a4ed1ce029 100644 (file)
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -3284,7 +3284,7 @@ const AVClass *avcodec_get_subtitle_rect_class(void);
  * can use this AVCodecContext to decode/encode video/audio data.
  *
  * @param dest target codec context, should be initialized with
- *             avcodec_alloc_context3(), but otherwise uninitialized
+ *             avcodec_alloc_context3(NULL), but otherwise uninitialized
  * @param src source codec context
  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
  */