Vehicle Identification Number (VIN) Code Inspection
Cognex Deep Learning OCR tool recognizes deformed characters
A vehicle identification number, or VIN code, is a multi-character code used as a unique identifier for automobiles. VIN codes contain letters and numbers and may be direct part-marked (DPM); etched or scribed onto a metal plate; or printed on a sticker. Automotive manufacturers must be able to locate and decode VIN codes for successful traceability. Specular light, paint colors, and glare make it difficult for a machine vision system to locate and recognize characters. An inspection system needs to tolerate reflective surfaces which challenge image formation in order to successfully decode characters.
With the Cognex Deep Learning OCR tool, it is now easy to locate and read deformed characters, despite image formation challenges. To train the software, an engineer defines the region of interest on images which contain a representative set of VIN code characters. The OCR tool's pre-trained omni-font capabilities recognize characters even if they are obscured by glare and contrast. . During training and validation, a technician re-labels only the missed characters until the software’s model correctly identifies all characters. This new deep learning-based approach to OCR saves time during training and development by reducing excessive labeling and successfully reads characters on very noisy backgrounds.