The offsets are not random, but algorithmic, using the GCJ-02 datum.  Of course, legal access to use the GCJ-02 algorithms requires that you kowtow to the Chinese government:<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Restrictions_on_geographic_data_in_China" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Restrictions_on_geographic_dat...</a>