Freehand Drawings over Multimedia Maps as Analytical and Communication Tool

The paper describes the methods to preserve and communicate observations made during visual analysis and exploration of geographic information. The patterns observed on a map showing attributive information are highlighted using freehand drawings. These drawings are encoded in geographical coordinates and attached to maps together with a description of the observed phenomena. Each drawing or mark indicates a spatial pattern and bind it with the data that prompted it. The marks allow navigation between data and expressed patterns, simplify the analysis of behavior of the observed phenomena in time and help the search of dependencies between data elements. Use of marks as a selection mechanism can help to locate the objects that lay inside or close to the annotated area and thus having a potential influence on the observed pattern. In a collaborative environment, the analysts can exchange their annotated maps, discuss and comment them and come to common decisions.