“…Other techniques are: multi-scale spatial pyramid (MSSP), it captures the geometry of retina at multiple scales [19]; geodesic distance method (GDM), it can locate pixels in boundaries of layers [43]; convolutional neural network (CNN), it is pooling, which is a non-linear down-sampling [28,108,120]; dynamic programming (DP), it is a method that divide problems and solves each one separately [65,100,102]; canny edge detection, it is an algorithm that detects edges [97,99,104]; markov gibbs random field (MGRF), it allows to derive a global texture description by specifying local properties of textures [98]; loosely coupled level sets (LCLS), it is a technique that uses local intensity variations to segment layers [101]; structure tensor, it utilizes the gradient of a point with neighborhood to get directions of segmentation [102,104]; Randon Forest (RF), that train the data to estimate boundary probabilities [111,121,122]; and OTSU algorithm, it is used to perform automatic image thresholding [102,107,112]. In Figure 3 is shown an example of segmentation approach applied to an OCT image, in which the top boundary of the ILM and RPE layers are highlighted.…”