Abstract: Combustion flame temperature measurement is important for combustion status diagnosis which is widely used to improveengine combustion. A two-color temperature measurement calculation model was established based on digital image processing technology, optical and radiological knowledge. Flame images obtained by a color CCD (charge coupled device) camera were used to produce temperature field and then to extract color matrix information using a calibration and calculation software programed by authors with MATLAB software. The system can be used to batch process calibrated image. The calibration parameter curve from two-color method was using to get the temperature field in gray scale or pseudo-color image, and the statistical value of the temperature field. The results show that calculation results and the measurement results are basically the same.

Key words: combustion flame of engine, temperature measurement, two-color method, flame image, digital image processing, soot