The invention discloses an improved Retinex image defogging method. The method comprises the following steps of: inputting a
haze image, estimating n(x,y) firstly and removing n(x,y) according to a new expression formula, wherein n(x,y) is estimated by use of
gaussian filter because n(x,y) is caused by
direct imaging of
airglow, transforms slowly and belongs to a
low frequency part; subtracting the estimated n(x,y) from an original drawing, normalizing the obtained values, and acquiring an intermediate result; carrying out
gaussian filter on the intermediate result according to a single-scale
Retinex algorithm, estimating an illumination component, and removing the estimated illumination component L(x,y) from the intermediate result in a
Log domain; and carrying out automatic color
gradation processing on the obtained result, eliminating an overexposure phenomenon in the result, and outputting the processed result. According to the improved Retinex image defogging method, the defogging effect is greatly improved, the distant scenery becomes clear, detail parts become obvious, the running speed is rapid and the real-time requirement can be satisfied.