avutil/frame: add helper for getting side data from array

libavutil/frame.c

@@ -813,16 +813,26 @@ int av_frame_side_data_clone(AVFrameSideData ***sd, int *nb_sd,
     return 0;
 }
 
-AVFrameSideData *av_frame_get_side_data(const AVFrame *frame,
+const AVFrameSideData *av_frame_side_data_get(const AVFrameSideData **sd,
+                                              const int nb_sd,
                                               enum AVFrameSideDataType type)
 {
-    for (int i = 0; i < frame->nb_side_data; i++) {
-        if (frame->side_data[i]->type == type)
-            return frame->side_data[i];
+    for (int i = 0; i < nb_sd; i++) {
+        if (sd[i]->type == type)
+            return sd[i];
     }
     return NULL;
 }
 
+AVFrameSideData *av_frame_get_side_data(const AVFrame *frame,
+                                        enum AVFrameSideDataType type)
+{
+    return (AVFrameSideData *)av_frame_side_data_get(
+        (const AVFrameSideData **)frame->side_data, frame->nb_side_data,
+        type
+    );
+}
+
 static int frame_copy_video(AVFrame *dst, const AVFrame *src)
 {
     int planes;

libavutil/frame.h

@@ -1041,6 +1041,20 @@ AVFrameSideData *av_frame_side_data_new(AVFrameSideData ***sd, int *nb_sd,
 int av_frame_side_data_clone(AVFrameSideData ***sd, int *nb_sd,
                              const AVFrameSideData *src, unsigned int flags);
 
+/**
+ * Get a side data entry of a specific type from an array.
+ *
+ * @param sd    array of side data.
+ * @param nb_sd integer containing the number of entries in the array.
+ * @param type  type of side data to be queried
+ *
+ * @return a pointer to the side data of a given type on success, NULL if there
+ *         is no side data with such type in this set.
+ */
+const AVFrameSideData *av_frame_side_data_get(const AVFrameSideData **sd,
+                                              const int nb_sd,
+                                              enum AVFrameSideDataType type);
+
 /**
  * @}
  */