地图缓存技术显示模式的研究

Display-Mode Research of Map Cache Technology

地图缓存是快速访问地图服务的有效方式,目前流行的Google地图,MapBar地图,ArcGIS Online等在线地图都是通过地图缓存的方式提供高效的访问速度。JPEG格式由于其超强的压缩能力以及卓越的图像品质一直是缓存图片格式的首选。但是,在实际应用中也经常出现诸如"项圈"等差强人意的显示效果。针对这种情况,本文提出一种融JPEG与PNG32于一体的混合缓存模式,并通过验证表明,该模式有效提高了地图缓存的显示效果。

Map cache is the effective way to access map services,by which the popular Google Maps,MapBar map,ArcGIS Online and other online maps provide efficient map services.Because of its superior compression capabilities and excellent image quality,JPEG format has been always the choice of cache image format,but in practice there are often unsatisfied displays like 'Neck-Circle'.In response,this paper presents a way of combining JPEG and PNG to the mixed-cache mode,and experiments verified show that this model improves the appearance of the map cache effectively.