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가상 데이터를 활용한 번호판 문자 인식 및 차종 인식 시스템 제안

Proposal for License Plate Recognition Using Synthetic Data and Vehicle Type Recognition System

  • 이승주 (서울과학기술대학교 일반대학원 미디어IT공학과) ;
  • 박구만 (서울과학기술대학교 전자IT미디어공학과)
  • Lee, Seungju (Dept. of Media IT Engineering, The Graduate Schol, Seoul National University of Science and Technology) ;
  • Park, Gooman (Dept. of Electronic IT Media Engineering, Seoul National University of Science and Technology)
  • 투고 : 2020.07.16
  • 심사 : 2020.08.31
  • 발행 : 2020.09.30

초록

본 논문에서는 딥러닝을 이용한 차종 인식과 자동차 번호판 문자 인식 시스템을 제안한다. 기존 시스템에서는 영상처리를 통한 번호판 영역 추출과 DNN을 이용한 문자 인식 방법을 사용하였다. 이러한 시스템은 환경이 변화되면 인식률이 하락되는 문제가 있다. 따라서, 제안하는 시스템은 실시간 검출과 환경 변화에 따른 정확도 하락에 초점을 맞춰 1-stage 객체 검출 방법인 YOLO v3를 사용하였으며, RGB 카메라 한 대로 실시간 차종 및 번호판 문자 인식이 가능하다. 학습데이터는 차종 인식과 자동차 번호판 영역 검출의 경우 실제 데이터를 사용하며, 자동차 번호판 문자 인식의 경우 가상 데이터만을 사용하였다. 각 모듈별 정확도는 차종 검출은 96.39%, 번호판 검출은 99.94%, 번호판 검출은 79.06%를 기록하였다. 이외에도 YOLO v3의 경량화 네트워크인 YOLO v3 tiny를 이용하여 정확도를 측정하였다.

In this paper, a vehicle type recognition system using deep learning and a license plate recognition system are proposed. In the existing system, the number plate area extraction through image processing and the character recognition method using DNN were used. These systems have the problem of declining recognition rates as the environment changes. Therefore, the proposed system used the one-stage object detection method YOLO v3, focusing on real-time detection and decreasing accuracy due to environmental changes, enabling real-time vehicle type and license plate character recognition with one RGB camera. Training data consists of actual data for vehicle type recognition and license plate area detection, and synthetic data for license plate character recognition. The accuracy of each module was 96.39% for detection of car model, 99.94% for detection of license plates, and 79.06% for recognition of license plates. In addition, accuracy was measured using YOLO v3 tiny, a lightweight network of YOLO v3.

키워드

참고문헌

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