一种基于DCT变换的数字水印算法在“天地图·广东”中的应用

A Novel Watermarking Solution for Guangdong Public Geographic Information System Online Map

地理信息公共服务通过云平台进行部署和发布,可以使得其应用于政府部门和社会的空间数据服务更加高效和稳定。然而,把对应的地图信息挂载在云平台供应商处同时也加大了防止电子地图被盗用的难度。本文针对"天地图?广东"的电子地图瓦片,提出了一种具有高鲁棒性、基于离散余弦变换(DCT)的数字水印算法,在寄存云端和公开发布的电子地图中隐藏生产单位版权的数字水印图片,藉此来跟踪、抵制"天地图"图片数据的非法流通,非法复制,有效地保护数据生产单位的合法权益。

Nowadays, The services of Public Geographic Information System are more stable and effective by means of the cloud technology. Somehow, it causes more difficulties for protected the electronic map data be stolen since the map data need to be uploaded to the cloud service provider. In this paper, a novel watermark solution with high robustness is proposed to applied in the GIS public version of Guangdong province, namely＂Tianditu ·uangdong＂. The solution is based on Discrete Cosine Transform （DCT）, embed the watermark of map producer into the map to prevent illegal circulation and protect intellectual property rights.