applies a Perona–Malik diffusion filter to image.
specifies the amount of diffusion time t to be applied.
uses a conductance parameter k.
applies a Gaussian regularization of width σ to the image gradient in the conductance function.
- Perona–Malik filtering is an inhomogeneous diffusion method typically used for smoothing images while preserving edges.
- PeronaMalikFilter works on arbitrary grayscale or multichannel images, operating on each channel separately.
- applies the diffusion equation to every image channel .
- The function of the σ-regularized gradient norm defines the conductance of the diffusion current. At edges where the gradient norm is large in comparison to k, diffusion is suppressed, thereby preserving edges.
- In PeronaMalikFilter[image,t], t parameterizes the evolution of the diffusion and thereby the spatial range of the filter.
- The conductance parameter k can take any positive value. The default value of k is Automatic, which assigns to k the 50% quantile of the gradient norm of image. If more than one channel is present, the gradient norm of the channel average is taken into account.
- The regularization parameter σ is the standard deviation of the Gaussian kernel , with which the image gradient is convolved. The σ-regularization makes the conductance term less susceptible to noise. If , a finite difference scheme is used to determine the gradient.
- PeronaMalikFilter[image] is equivalent to PeronaMalikFilter[image,1,Automatic,0].