+ for (i = 0; i < graph->nb_filters; i++)
+ swap_samplerates_on_filter(graph->filters[i]);
+}
+
+#define CH_CENTER_PAIR (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)
+#define CH_FRONT_PAIR (AV_CH_FRONT_LEFT | AV_CH_FRONT_RIGHT)
+#define CH_STEREO_PAIR (AV_CH_STEREO_LEFT | AV_CH_STEREO_RIGHT)
+#define CH_WIDE_PAIR (AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT)
+#define CH_SIDE_PAIR (AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT)
+#define CH_DIRECT_PAIR (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)
+#define CH_BACK_PAIR (AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT)
+
+/* allowable substitutions for channel pairs when comparing layouts,
+ * ordered by priority for both values */
+static const uint64_t ch_subst[][2] = {
+ { CH_FRONT_PAIR, CH_CENTER_PAIR },
+ { CH_FRONT_PAIR, CH_WIDE_PAIR },
+ { CH_FRONT_PAIR, AV_CH_FRONT_CENTER },
+ { CH_CENTER_PAIR, CH_FRONT_PAIR },
+ { CH_CENTER_PAIR, CH_WIDE_PAIR },
+ { CH_CENTER_PAIR, AV_CH_FRONT_CENTER },
+ { CH_WIDE_PAIR, CH_FRONT_PAIR },
+ { CH_WIDE_PAIR, CH_CENTER_PAIR },
+ { CH_WIDE_PAIR, AV_CH_FRONT_CENTER },
+ { AV_CH_FRONT_CENTER, CH_FRONT_PAIR },
+ { AV_CH_FRONT_CENTER, CH_CENTER_PAIR },
+ { AV_CH_FRONT_CENTER, CH_WIDE_PAIR },
+ { CH_SIDE_PAIR, CH_DIRECT_PAIR },
+ { CH_SIDE_PAIR, CH_BACK_PAIR },
+ { CH_SIDE_PAIR, AV_CH_BACK_CENTER },
+ { CH_BACK_PAIR, CH_DIRECT_PAIR },
+ { CH_BACK_PAIR, CH_SIDE_PAIR },
+ { CH_BACK_PAIR, AV_CH_BACK_CENTER },
+ { AV_CH_BACK_CENTER, CH_BACK_PAIR },
+ { AV_CH_BACK_CENTER, CH_DIRECT_PAIR },
+ { AV_CH_BACK_CENTER, CH_SIDE_PAIR },
+};