extern gchar *opt_input_format;
extern gchar *opt_output_format;
extern gchar *opt_transform_module;
-extern gchar *opt_show;
+extern gboolean opt_show;
extern gchar *opt_time;
extern gchar *opt_samples;
extern gchar *opt_frames;
-extern gchar *opt_continuous;
+extern gboolean opt_continuous;
extern gchar *opt_get;
-extern gchar *opt_set;
+extern gboolean opt_set;
int parse_options(int argc, char **argv);
void show_help(void);