Baidu Maps

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Baidu Maps (百度地图)
Baidu map for Shanghai, China, using the Sim City style.png
Screenshot of the Sim City-like style that Baidu Maps offers for the city of Shanghai, China.
Type of site
Web mapping
Available in Chinese
Owner Baidu
Website Baidu Maps
Commercial Yes
Launched 2005; 13 years ago (2005)
Current status Active

Baidu Maps is a desktop and mobile web mapping service application and technology provided by Baidu, offering satellite imagery, street maps, street view ("Panorama" - zh:百度全景) and indoor view[1] perspectives, as well as functions such as a route planner for traveling by foot, car, or with public transportation. Android and iOS applications are available.

Baidu Maps is available only in the Chinese language and before 2016, it offered maps only of mainland China, Hong Kong, Macau and Taiwan, the rest of the world appearing unexplored.[2] Currently Baidu Maps also offers maps of various other countries.[3] It's reported that more than 150 countries will be supported by the end of 2016.[4] Baidu uses map data supplied by NavInfo, MapKing, Here, LocalKing and OpenStreetMap.[5]

In 2016, it is reported that Baidu Maps has over 348 million monthly active users, and will "transform from a Chinese map provider to a world map provider and become the Chinese brand that provides global services for mobile travel applications", which also outlines Baidu's plans for global expansion.[6][7]

Countries and territories supported[edit]

History[edit]

  • September 2005 - Baidu Maps is released
  • 2010 - Baidu adds a unique 3D highly detailed view for select cities, very similar to the computer game SimCity.[8] The images are licensed from digital mapping service Edushi.[9] Cities being currently covered include Beijing, Shanghai, Guangzhou and Shenzhen.
  • November 2011 - Baidu launches satellite imagery with much better resolution for the Greater China region than Google Maps[10] City-level only includes Beijing, Shanghai, Guangzhou, Shenzhen, Hong Kong, Macao and other major cities.
  • September 3, 2012 - at its annual Baidu World event, Baidu reveals 360-degree digital imagery for select buildings[9]

Coordinate system[edit]

Baidu Map with WGS-84, GCJ-02 and BD-09 markers
Screenshot of Baidu Map with WGS-84, GCJ-02 and BD-09 markers

Baidu Map uses a variant of web Mercator projection for slicing map data into tiles, with distances expressed in degrees. It's associated with an underlying latitude-longitude reference. However, the reference uses the BD-09 coordinate system, which adds further obfuscation to the already obfuscated national standard in China, GCJ-02[11] (which in turn is defined in terms of the de facto standard around the world, WGS 84). Baidu alleges that adopting BD-09 "protects users' privacy".[12]

The Baidu Map API documentation specifies that "real" (WGS-84) GPS coordinates must be converted via a coordinate conversion interface.[13] An HTTP interface, JavaScript API, Android SDK, and iOS SDK are available.

The JavaScript coordinate conversion API is demonstrated online by Baidu, but without any reverse (to GCJ-02) conversion capabilities.[14] Open source implementations in R [15] and various other languages[16] exist, implemented in a manner much like the reverse GCJ-02 algorithm.

BD-09's lat-lon coordinates are derived by scrambling a polar version of GCJ-02 coordinates and adding a fixed offset:[15]

from cmath import polar, rect
from math import sin, cos, pi
# Represent coordinates with complex numbers for simplicity
coords = complex

# baidu assumes x/real: lon; y/imag: lat here.
def gcj_bd(gcj: coords) -> coords:
    r, θ = polar(gcj)
    r += 2e-5 * sin(gcj.imag * pi * 3000 / 180)
    θ += 3e-6 * cos(gcj.real * pi * 3000 / 180)
    return rect(r, θ) + (0.0065 + 0.006j)

Street view service[edit]

The street view service of Baidu Maps was first launched on August 21, 2013.[17] This is a list of cities supported as of March 11, 2015:

Provincial level division City
Beijing Beijing
Shanghai Shanghai
Tianjin Tianjin
Chongqing Chongqing
Liaoning Shenyang, Liaoyang, Dalian, Fushun, Panjin, Jinzhou, Chaoyang, Dandong, Yingkou
Jilin Changchun, Jilin City, Tonghua, Yanbian Korean Autonomous Prefecture, Songyuan, Baicheng
Heilongjiang Harbin, Daqing, Qiqihar, Mudanjiang, Jiamusi
Shanxi Taiyuan, Jinzhong, Shuozhou, Xinzhou, Lüliang, Yangquan, Linfen, Changzhi, Yuncheng
Shandong Jinan, Qingdao, Tai'an, Weifang, Rizhao, Weihai, Jining, Yantai, Dongying, Binzhou, Liaocheng
Anhui Hefei, Wuhu, Huangshan City, Lu'an
Jiangsu Nanjing, Suzhou, Wuxi, Yangzhou, Changzhou, Xuzhou, Lianyungang, Yancheng, Huai'an, Nantong, Zhenjiang, Suqian
Zhejiang Hangzhou, Jiaxing, Ningbo, Huzhou, Shaoxing, Zhoushan, Lishui, Taizhou, Quzhou
Hebei Shijiazhuang, Baoding, Langfang, Qinhuangdao, Chengde, Tangshan, Zhangjiakou
Henan Zhengzhou, Kaifeng, Anyang, Xinxiang, Luoyang, Shangqiu, Xuchang, Pingdingshan, Zhoukou, Zhumadian, Xinyang, Jiaozuo
Hubei Xiangyang, Jingmen, Jingzhou, Shiyan, Suizhou, Huangshi
Hunan Changsha, Zhangjiajie, Xiangxi Tujia and Miao Autonomous Prefecture
Jiangxi Nanchang, Jiujiang, Jingdezhen, Ji'an, Shangrao
Fujian Fuzhou, Xiamen, Quanzhou, Putian, Zhangzhou, Nanping
Guangdong Guangzhou, Shenzhen, Dongguan, Qingyuan, Jiangmen, Zhongshan, Zhuhai, Zhanjiang, Foshan, Shantou, Shanwei, Jieyang
Guangxi Liuzhou, Guilin, Beihai, Qinzhou, Fangchenggang, Yulin, Guangxi, Guigang, Chongzuo, Baise
Hainan Haikou, Sanya, Danzhou, Wenchang, Tunchang County, Qionghai, Wanning, Lingshui Li Autonomous County, Wuzhishan City, Dongfang, Hainan, Ding'an County,

Chengmai County, Lingao County, Changjiang Li Autonomous County, Ledong Li Autonomous County, Qiongzhong Li and Miao Autonomous County, Baoting Li and Miao Autonomous County

Inner Mongolia Hohhot, Hulunbuir, Ordos City, Baotou, Hinggan League, Chifeng, Tongliao
Ningxia Yinchuan, Wuzhong, Zhongwei
Gansu Lanzhou, Jiuquan, Zhangye, Jiayuguan City, Qingyang, Pingliang, Tianshui, Wuwei
Qinghai Xining, Golmud, Yushu Tibetan Autonomous Prefecture, Haibei Tibetan Autonomous Prefecture, Hainan Tibetan Autonomous Prefecture
Shaanxi Xi'an, Yulin, Baoji, Yan'an, Xianyang, Hanzhong
Yunnan Kunming
Tibet Autonomous Region Lhasa (prefecture-level city), Shigatse, Nagqu Prefecture, Lhoka (Shannan) Prefecture
Xinjiang Aksu, Kashgar, Turpan, Hotan Prefecture
Hong Kong Hong Kong
Macau Macau

References[edit]

  1. ^ "Indoor view of Chinese restaurant". Baidu Maps. Retrieved 5 April 2015. 
  2. ^ "Why do Baidu and Tencent QQ Map(s) only show China, and blank for the rest of the world?". 5 April 2015. 
  3. ^ "百度地图和支付宝抢在春节前登陆日本". 环球网. 2016-02-01. Retrieved 2016-02-14. 
  4. ^ "百度地图宣布国际化战略 年底覆盖150个国家". 百度. 2016-04-22. Retrieved 2016-06-26. 
  5. ^ Lee, Mark (6 July 2012). "Apple Shares Google China Map Partner in Win for AutoNavi: Tech". Bloomberg. 
  6. ^ "Baidu maps out global expansion - Business - Chinadaily.com.cn". www.chinadaily.com.cn. 
  7. ^ https://expandedramblings.com/index.php/baidu-stats/.  Missing or empty |title= (help)
  8. ^ "Baidu beats Google when it comes to mapping". 23 November 2010. Retrieved 5 April 2015. 
  9. ^ a b Millward, Steven (3 September 2012). "Baidu Maps Gets 8-Bit 3D Views, Makes Real Life Feel Like Sim City [UPDATED]". TechInAsia. Retrieved 5 April 2015. 
  10. ^ Custer, Charlie (6 November 2011). "Baidu Maps Launches Satellite View". TechInAsia. Retrieved 5 April 2015. 
  11. ^ "Frequently Asked Questions". developer.baidu.com/map (in Chinese). Baidu. 
  12. ^ "Baidu LBS Open Platform FAQ". Baidu Developer. Retrieved 2016-12-19. 
  13. ^ "Coordinate Conversion API". developer.baidu.com/map (in Chinese). Baidu. 
  14. ^ "Conversion from GCJ-02 coordinates used by Google Maps in China to BD-09". Baidu Map JavaScript demos (in Chinese). 
  15. ^ a b "A package for geocoding, reverse geocoding and coordinate transformations between WGS-84, GCJ-02 and BD-09 coordinate systems". 15 February 2014. 
  16. ^ Lee, Googol. "Transform coordinates between Earth (WGS-84) and Mars in China (GCJ-02)". 
  17. ^ "百度全景:真实世界 百度地图触手可及". 

External links[edit]