On the Efficiency of the Mean Intercept Length Tensor

The Mean Intercept Length tensor is one of the most used techniques to estimate microstructure orientation and anisotropy of materials from 2D or 3D binary images. This paper proposes an efficient implementation of this technique. First, the Extended Gaussian Image is computed for the binary image. Second, the intercepts are computed for all possible orientations through an angular convolution. Finally, the tensor is computed by means of the covariance matrix. The complexity of the method is O(n+m) in contrast with O(nm) of traditional implementations, where n is the number of voxels in the image and m is the number of orientations used in the computations.