public static extern void liq_set_last_index_transparent(liq_attr_ptr attr, int is_last);
public static extern liq_image_ptr liq_image_create_rgba(liq_attr_ptr attr, [In, MarshalAs(UnmanagedType.LPArray)] byte[] bitmap, int width, int height, double gamma);
public static extern liq_error liq_set_quality(liq_attr_ptr attr, int minimum, int maximum);
public static extern int liq_get_max_quality(liq_attr_ptr attr);
public static extern liq_error liq_set_min_posterization(liq_attr_ptr attr, int bits);
public static extern int liq_get_min_posterization(liq_attr_ptr attr);
public static extern liq_error liq_set_min_opacity(liq_attr_ptr attr, int min);
public static extern int liq_get_min_opacity(liq_attr_ptr attr);
public static extern liq_error liq_set_speed(liq_attr_ptr attr, int speed);
public static extern int liq_get_speed(liq_attr_ptr attr);
public static extern int liq_get_max_colors(liq_attr_ptr attr);
public static extern liq_error liq_set_max_colors(liq_attr_ptr attr, int colors);
public static extern void liq_attr_destroy(liq_attr_ptr attr);
public static extern liq_attr_ptr liq_attr_copy(liq_attr_ptr attr);
public static extern liq_result_ptr liq_quantize_image(liq_attr_ptr attr, liq_image_ptr input_image);