+void parse_options(void *optctx, int argc, char **argv, const OptionDef *options,
+ void (* parse_arg_function)(void *optctx, const char*));
+
+/**
+ * Parse one given option.
+ *
+ * @return on success 1 if arg was consumed, 0 otherwise; negative number on error
+ */
+int parse_option(void *optctx, const char *opt, const char *arg, const OptionDef *options);
+
+/**
+ * Check if the given stream matches a stream specifier.
+ *
+ * @param s Corresponding format context.
+ * @param st Stream from s to be checked.
+ * @param spec A stream specifier of the [v|a|s|d]:[<stream index>] form.
+ *
+ * @return 1 if the stream matches, 0 if it doesn't, <0 on error
+ */
+int check_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec);
+
+/**
+ * Filter out options for given codec.
+ *
+ * Create a new options dictionary containing only the options from
+ * opts which apply to the codec with ID codec_id.
+ *
+ * @param s Corresponding format context.
+ * @param st A stream from s for which the options should be filtered.
+ * @return a pointer to the created dictionary
+ */
+AVDictionary *filter_codec_opts(AVDictionary *opts, enum CodecID codec_id, AVFormatContext *s, AVStream *st);