This video demonstrates, step by step, how to create contour and DEM ( Digital Elevation Model) using free tools : Google Earth, TCX Converter and QGIS 2.10.
You know that QGIS can generates DEM and contours from a points cloud which contains altitude information.
So, we used the Path tool in Google Earth to create the points cloud and we exported them to a KML file.
Then, we used TCX Converter to get altitude data of the points (internet connection needed) and export them to a CSV file.
Finally, we imported the CSV in QGIS 2.10 and we used SAGA tools to generate a DEM and contour lines.
You can download TCX Converter here : TCX-C-Experience_2032_Windows.zip