In this paper we characterize a liquefied gas flame by means of infrared image processing aimed to obtain variables that relates the infrared digital data with the combustion process. An infrared camera that capture radiation between 8[µm] to 12[µm] was used, different techniques as the histogram and FFT (fast Fourier transform) were calculated from infrared images and used for the data processing of different variables like axial and radial profiles, radiative zones, peaks of radiation and a frequency analysis of the reaction zone under different combustion conditions. The experimental results have shown a high correlation between the analyzed variables and the air rate conditions making the infrared radiation analysis an important tool for the flame sensing.