+/* The presets can also be indexed numerically, as in:
+ * x264_param_default_preset( ¶m, "3", ... )
+ * with ultrafast mapping to "0" and placebo mapping to "9". This mapping may
+ * of course change if new presets are added in between, but will always be
+ * ordered from fastest to slowest.
+ *
+ * Warning: the speed of these presets scales dramatically. Ultrafast is a full