A remarkably facile automated numerical data extraction tool from oscilloscope screen snapshots

In this study, we show the results of some traditional experiments, performed by using an inexpensive dual-trace cathode ray oscilloscope (CRO), combined with an automated data extraction tool (based on image processing techniques) to learn about their fundamentals. This tool, called a WebPlotDigitizer (WPD) is an opensource software program (https://automeris.io/WebPlotDigitizer/download.html) to extract numerical data from a variety of plots uploaded as an image. We emphasize that the WPD is an exceptionally versatile and easy-to-use tool that works both online (within web browsers) and offline. We also show that it is a straightforward and speedy tool to reproduce the results with pragmatic accuracy. Here, we processed CRO screen snapshots (images) acquired using a digital camera (or smart phone), by WPD to extract the numerical data of the waveforms (curves) and then replotted them. We then suggested the execution of numerical simulations on the extracted data to enhance the fascination of the practical work. The results obtained with this instructive and easy tool are considerably well matched with theory and are more precise than those obtained with the tedious traditional methods of manually tracing the temporal waveforms. To the best of our knowledge, this work is unique and innovative, giving a prescription to bridge between CRO-assisted laboratory experiments and image processing. In our view, the proposed study not only benefits physics and engineering students, but young faculty members working in an electronics laboratory and those concerned with image processing, electronic circuits and instruments. (paper)