The Research Institute for Geo-hydrological Protection of Turin (IRPI Turin), of the Italian National Research Council, has an extensive collection of aerial photograms, on paper format. It covers the entire Po Basin and other river basins in northern Italy. Flights involve a period ranging from 1954 to 2003. Part of the archive consists of copies made by other local authorities (Military Geographical Institute, regional and provincial administrations, ...) while other photograms were made by CNR on watercourses and areas affected by natural events located in its area of competence. Flight plans, divided by IGM sheets at 1:100000 scale, were acquired in raster format on A0 size scanner and then geo-referenced according to the UTM-WGS84 reference system. The cover areas of each photogram were manually digitized in vector format and in the associated table, by semiautomatic procedures, the photogram encoding has been attributed to any single object. This tagging was appropriately structured to include in the image name: time, spatial and management data, associated uniquely to each image during scanning. The entire set of frames is being input into a GIS system, implemented in software ArcMap 9.x (TM), integrated with geographic layers, such as hydrography, administrative boundaries, etc.. Within that system, through automated procedures, developed in Model Builder (TM) environment, the operator can perform queries to identify sets of images depending on the area of interest (river, municipality ...) and produce a report that lists photograms selected by the procedure for the optimized file retrieval and their coverage display. This integrated system will allow an optimal use of resources from the photo archive with the possibility of using images in Institute's internal projects and for use by other applicants such as other institutions or professionals.
Il lavoro di scansione dei fotogrammi aerei cartacei e dei piani di volo in atto dal 2009 è stato completato, sono stati digitalizzati 170.000 fotogrammi in formato 23x23 cm impiegando prima uno scanner Umax formato A3 successivamente con uno scanner Fujitsu dotato di avanzamento automatico ADF , con l'impiego di uno scanner a grande formato in dotazione all'Istituto sono stati digitalizzati 1100 piani di volo cartacei. Contestualmente allo svolgimento del lavoro di base riguardante la scansione dei fotogrammi è iniziata la georeferenziazione dei piani volo digitalizzati con l'impiego del software GIS Arc Map, in questa fase per ogni piano di volo sono state georiferite le tracce dei fotogrammi su territorio con la formazione di un poligono per ogni fotogramma, utilizzando come riferimento il sistema geografico di coordinate UTM ETRS89. Ogni poligono è stato identificato con il nome del fotogramma rappresentato usando la codifica evidenziata nell'allegato 1. I piani di volo sono generalmente disegnati alla scala 1:100000 tranne poche eccezioni, la georeferenziazione è stata realizzata utilizzando come riferimento i vertici dei Fogli IGM alla scala 1:100000 le cui coordinate sono state acquisite direttamente dall'Istituto Geografico Militare di Firenze. Attualmente sono i corso le fasi di lavoro della georeferenziazione e una attività di revisione del collegamento informatico fra la codifica dei fotogrammi e la loro posizione all'interno delle unità di memorizzazione di massa.
Progetto per l'informatizzazione della aerofototeca
Franco Godone
2016
Abstract
The Research Institute for Geo-hydrological Protection of Turin (IRPI Turin), of the Italian National Research Council, has an extensive collection of aerial photograms, on paper format. It covers the entire Po Basin and other river basins in northern Italy. Flights involve a period ranging from 1954 to 2003. Part of the archive consists of copies made by other local authorities (Military Geographical Institute, regional and provincial administrations, ...) while other photograms were made by CNR on watercourses and areas affected by natural events located in its area of competence. Flight plans, divided by IGM sheets at 1:100000 scale, were acquired in raster format on A0 size scanner and then geo-referenced according to the UTM-WGS84 reference system. The cover areas of each photogram were manually digitized in vector format and in the associated table, by semiautomatic procedures, the photogram encoding has been attributed to any single object. This tagging was appropriately structured to include in the image name: time, spatial and management data, associated uniquely to each image during scanning. The entire set of frames is being input into a GIS system, implemented in software ArcMap 9.x (TM), integrated with geographic layers, such as hydrography, administrative boundaries, etc.. Within that system, through automated procedures, developed in Model Builder (TM) environment, the operator can perform queries to identify sets of images depending on the area of interest (river, municipality ...) and produce a report that lists photograms selected by the procedure for the optimized file retrieval and their coverage display. This integrated system will allow an optimal use of resources from the photo archive with the possibility of using images in Institute's internal projects and for use by other applicants such as other institutions or professionals.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
