This is a free Windows program that enables you to extract the underlying data from a graph. The graph can be loaded as a bitmap or scanned directly from hardcopy from within the program. The program will accomodate linear, log-linear and log-log plots, and will work with scatter plots, line plots or barcharts.
Digitizing data from the graph: Data can be extracted manually, or by an automated process for linear plots or certain scatter plots with large amounts of data. The data can be viewed in tabular or graphical form, and saved to an Excel file for further analysis.