Introduction - If you have any usage issues, please Google them yourself
Google maps of each cutting method of cutting a small picture is 256* 256 (pixels), common sense to judge each picture on behalf of the actual length and width ratio of the region should be 2:1, but because of the existence of different projection, in fact, it is one : 1, as the deal between the process of how I did not engage in to understand. About 51ditu