Combustion is a very complex reactive fluid dynamical process. A thorough analysis is a prerequisite to reduce pollutant emissions, for fuel economy, for the optimization of burner performance and for on-line control purposes. Local point measurements (e.g. with thermocouples or local radiation pyrometry and spectroscopic methods) give only a little information to characterize these spatially distributed and time dependent processes. Large array sensors like CCD-arrays provide us with an enormous amount of information; automatic image processing as well as pattern recognition methods give a much higher potential for the analysis of such processes and have the attraction of a non-contact and non-intrusive optical measurement technique. The literature shows a wide acceptance, and gives examples for the potential, of these methods.