Automatic Extraction of Data Points and Text Blocks from 2-Dimensional Plots in Digital Documents

Two dimensional plots (2-D) in digital documents on the web are an important source of information that is largely under-utilized. In this paper, we outline how data and text can be extracted automatically from these 2-D plots, thus eliminating a time consuming manual process. Our information extraction algorithm identifies the axes of the figures, extracts text blocks like axes-labels and legends and identifies data points in the figure. It also extracts the units appearing in the axes labels and segments the legends to identify the different lines in the legend, the different symbols and their associated text explanations. Our algorithm also performs the challenging task of separating out overlapping text and data points effectively. Our experiments indicate that these techniques are computationally efficient and provide acceptable accuracy.