Machine-Readable Zones Detection in Images Captured by Mobile Devices’ Cameras
S. I. Kolmakov, Natalya S. Skoryukina, Vladimir V. Arlazarov · Pattern Recognition and Image Analysis · 2020
Abstract The article deals with the detection of document machine-readable zones (MRZ) in images obtained with the aid of small-size digital cameras. The herein proposed method is based on the mutual arrangement of binarized image connected components. A graph is plotted the nodes of which are the center of the black connected components. Distribution of the graph edges provides information on the document orientation whereby the algorithm is made rotation-invariant. Paths which satisfy special requirements and highly likely correspond to the MRZ lines are searched for in the graph. Such paths are clustered and then the most consistent cluster is selected with due regard for knowledge on possible MRZ geometrical characteristics. The square enclosing this cluster is the answer to the algorithm. Tests performed on open sets of data showed substantial improvement in detection quality as compared with the state-of-the-art methods. The computational complexity of the algorithm allows its real-time use in mobile devices.