Local Directional Pattern How to Calculate Local Directional Pattern (LDP) Code? With Example |Kirsch Compass Mask| ~xRay Pixy Click here - > WATCH NOW What are Local Directional Patterns? LDP = Local Directional Pattern. Local Directional Pattern is a descriptor i.e., used for Face Recognition. What is Descriptor? Descriptors rely on Gradient-based or intensity variation approaches detect Local Features (e.g., Edges, Blobs and Regions). BLOB = Binary Large Object (i.e., the region of the image). Descriptors such as HOG, SIFT, SURF (rely on local gradient computation). Binary Descriptors such as BRISK, ORB or FREAK (rely on local intensity differences). Local Directional Pattern ( LDP) Assign code for each pixel in the image. Local Directional Pattern ( LDP) encoded image is divided into regions. How LDP Calculate? For Each pixel in the image LDP computes an 8-bit binary code. 8-bit binary pattern is calculated by involving the local regions of the image of size 3x3 with Kr