An Engauge Digitizer alternative with nothing to install
Engauge Digitizer is a free desktop program: you install it, import an image, set three axis points and then trace. Chart to Data runs in the browser and reads the axes and the data for you.
Why people switch
- Nothing to install or update.
- PDFs go in as they are: there is no need to export each figure as an image first.
- Several charts on a page, and all the pages of a paper, are read in one go.
How the values are checked
When a PDF holds the chart as a drawing (most figures in papers do), the values are read from the drawing itself. Nothing is estimated from pixels, so a point is as precise as the file is.
A picture (a screenshot, a scan, a PNG or JPEG) is read by an AI model. Every value is then drawn back on the picture as a ring, so a wrong one is easy to see and to correct in the table.
Questions
Can I correct a value?
Yes. The table beside the chart can be edited, rows can be added or removed, a missed point or series can be added by clicking on the chart, and the Excel file records what was changed by hand.