-int mp4_meta_get_by_index(const struct mp4 *f, unsigned int index,
- char **item, char **value);
-int32_t mp4_meta_update(struct mp4_callback *f,const struct mp4_metadata * data);
-
-int mp4_meta_get_num_items(const struct mp4 *f);
-int mp4_meta_get_artist(const struct mp4 *f, char **value);
-int mp4_meta_get_title(const struct mp4 *f, char **value);
-int mp4_meta_get_date(const struct mp4 *f, char **value);
-int mp4_meta_get_album(const struct mp4 *f, char **value);
-int mp4_meta_get_comment(const struct mp4 *f, char **value);
+struct mp4_metadata *mp4_get_meta(struct mp4 *f);
+int32_t mp4_meta_update(struct mp4 *f);
+char *mp4_meta_get_artist(const struct mp4 *f);
+char *mp4_meta_get_title(const struct mp4 *f);
+char *mp4_meta_get_date(const struct mp4 *f);
+char *mp4_meta_get_album(const struct mp4 *f);
+char *mp4_meta_get_comment(const struct mp4 *f);