The invention discloses a tamper detection method based on character position of vehicle VIN code, which comprises the following steps: obtaining vehicle VIN code image to be detected
in vehicle annual inspection and VIN code archiving image in
server; obtaining vehicle VIN code image to be detected
in vehicle annual inspection. Detecting an area where the VIN code is located, and judging whethera target exists or not; Dividing the VIN code into a
single character and judging whether the character matches the answer; constructing A
homography matrix by the positions of the first and last characters of the image to be detected and the archived image, and mapping the space of the image to be detected to the space of the archived image. Judging whether the positions of the transformed imagecharacters (the left-right spacing and the upper-lower position of the characters) are consistent with the positions of the image characters archived by the
server; If the above judgment exists and isconsistent, recording the flag as 0, otherwise recording the flag as 1, and saving the related picture; If the recording flag is 0, the vehicle VIN code tampering detection is passed, indicating thatthe VIN code has not been tampered with; if the recording flag is 1, the VIN code tampering detection is not passed, indicating that the VIN code has been tampered with. At the same time, according to the position where the flag 1 appears, obtain the reason why the calibration does not pass and the picture of the problem. The invention realizes the automatic
verification of the VIN code in the vehicle annual inspection, replaces the existing manual
verification mode, saves manpower, speeds up the
verification speed, can effectively detect whether the VIN code is tampered with, and ensures theopenness and fairness of the verification work.