avutil/frame: add helper for freeing arrays of side data

libavutil/frame.c

@@ -78,6 +78,11 @@ static void frame_side_data_wipe(AVFrame *frame)
     wipe_side_data(&frame->side_data, &frame->nb_side_data);
 }
 
+void av_frame_side_data_free(AVFrameSideData ***sd, int *nb_sd)
+{
+    wipe_side_data(sd, nb_sd);
+}
+
 AVFrame *av_frame_alloc(void)
 {
     AVFrame *frame = av_malloc(sizeof(*frame));

libavutil/frame.h

@@ -988,6 +988,17 @@ int av_frame_apply_cropping(AVFrame *frame, int flags);
  */
 const char *av_frame_side_data_name(enum AVFrameSideDataType type);
 
+/**
+ * Free all side data entries and their contents, then zeroes out the
+ * values which the pointers are pointing to.
+ *
+ * @param sd    pointer to array of side data to free. Will be set to NULL
+ *              upon return.
+ * @param nb_sd pointer to an integer containing the number of entries in
+ *              the array. Will be set to 0 upon return.
+ */
+void av_frame_side_data_free(AVFrameSideData ***sd, int *nb_sd);
+
 /**
  * @}
  */