Quality assurance during the thermal spraying by computational revision or alienation of digital images

is The invention relates to a method for thermal spraying to produce a spray layer on the surface of a substrate, said detected at least one quality of the sprayed layer influencing feature of the thermal spraying process by means of a digital camera, controlled and / or monitored, and a system for quality assurance in the forming a spray layer on the surface of a substrate by a thermal spraying method, comprising a digital camera to capture, control and / or monitoring at least one of the quality of the sprayed layer influencing feature of the thermal spraying process. DOLLAR A According to the invention associated with at least one region of equal intensity and / or at least one area within a certain intensity interval to one or more symmetrical geometric surface bodies in the images by computational revision and / or estrangement. The symmetrical geometric surface body can be detected as records and these records the quality of diagnosis can be made based on characteristic of the respective geometric shape features. Ellipses are preferably used as a symmetrical geometric surface body. The invention provides for quality assurance on a diagnosis, which is based on relatively small amounts of data, thereby on for the injection process and for the spray gun meaningful unique data is based.