Abstract: A computer-implemented method of converting time series data of at least one operational data source of a technical system into an image, includes providing a time series data of at least one operational data source of the technical system as a series of values of successive time stamps, wherein the values of the series of values vary over time. The method further includes the steps of assigning for each of the considered time stamps of the respective time series data either a value-depending color, a value-depending brightness, a value-depending pattern or a combination thereof to an image element of the image, and sequencing the image elements along a timeline, preferably without spaces between the image elements, to form for each time series data a set of linearly arranged image elements of the image.