The invention discloses an
image denoising method based on a
Contourlet transformation self-
adaptation direction threshold value, and belongs to the technical field of images. An elliptical direction neighborhood consistent with a sub-band energy gathering direction is adopted to calculate the self-
adaptation direction threshold value. The method comprises the steps that (1), an image with
noise I is input; (2),
Contourlet transformation is carried out on the I; (3), local
signal direction energy of a coefficient is estimated through the elliptical direction neighborhood; (4), a direction
energy factor of the coefficient is calculated according to the local
signal direction energy and dimension
signal average energy; (5), based on the Bayes criterion, a Bayes threshold value is corrected through the direction
energy factor to obtain the self-
adaptation direction threshold value; (6), based on soft threshold value rules, threshold value shrinkage is carried out on the coefficient with
noise through the self-adaptation direction threshold value; (7),
Contourlet inverse transformation is carried out through the shrunk coefficient to obtain a denoised image. The method can effectively remove the
noise, and clear image details can be kept.