期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：1980
卷号：XXIII Part B10
页码：795-814
出版社：Copernicus Publications
摘要：In the four year period since the last I.S.P. Congress atHelsinki, a large numher of mapping organisations have either enteredthe digital mapping field or have developed their existing capabilitysubstantially. Indeed there are few agencies of any size in the morehighly developed countries that do not have some digital mappingcapability, hov;ever limited or experimental this may be., It must berecognised however that, in quite a number of cases, this activity isbased on the digitizing of graphic documents, even though these areoften produced photogrammetrically in the first instance
