lavu/parseutils: add av_get_known_color_name()

libavutil/parseutils.h

@@ -98,6 +98,19 @@ int av_parse_video_rate(AVRational *rate, const char *str);
 int av_parse_color(uint8_t *rgba_color, const char *color_string, int slen,
                    void *log_ctx);
 
+/**
+ * Get the name of a color from the internal table of hard-coded named
+ * colors.
+ *
+ * This function is meant to enumerate the color names recognized by
+ * av_parse_color().
+ *
+ * @param color_idx index of the requested color, starting from 0
+ * @param rgbp      if not NULL, will point to a 3-elements array with the color value in RGB
+ * @return the color name string or NULL if color_idx is not in the array
+ */
+const char *av_get_known_color_name(int color_idx, const uint8_t **rgb);
+
 /**
  * Parse timestr and return in *time a corresponding number of
  * microseconds.