Scanning of Industrial Data Matrix Codes in non orthogonal view angle cases

In many cases, because of the lenses system of the video camera and because of the difficult areas to take a perfect straight picture with the Data Matrix Code, we face with the bad situation not to recognize the code and to extract the desired encoded information. For the Industrial Data Matrix Codes marked on planar surfaces with no perspective errors, the scanning process is performed based on the orientation angle of the pattern and the distance between modules. This method is simple and efficient for planar surfaces but for the cases when the Data Matrix Code image has hard perspective errors is useless. To achieve this, we describe an efficient method for scanning the Industrial Data Matrix Codes for the special situations like the perspective errors. An imaginary grid of points is constructed which has the same orientation as the surface. The imaginary grid is projected on to the image and following it, the Data Matrix Code Image is scanned extracting the binary information.