+/* common option values */
+#define AC3ENC_OPT_NONE -1
+#define AC3ENC_OPT_AUTO -1
+#define AC3ENC_OPT_OFF 0
+#define AC3ENC_OPT_ON 1
+#define AC3ENC_OPT_NOT_INDICATED 0
+#define AC3ENC_OPT_MODE_ON 2
+#define AC3ENC_OPT_MODE_OFF 1
+
+/* specific option values */
+#define AC3ENC_OPT_LARGE_ROOM 1
+#define AC3ENC_OPT_SMALL_ROOM 2
+#define AC3ENC_OPT_DOWNMIX_LTRT 1
+#define AC3ENC_OPT_DOWNMIX_LORO 2
+#define AC3ENC_OPT_ADCONV_STANDARD 0
+#define AC3ENC_OPT_ADCONV_HDCD 1