qrcoderecognitionbasedonimageprocessing

qrcoderecognitionbasedonimageprocessing内容摘要：

lted situation. 11 Tilt Correction • Fig2. Position Detection • As shown in fig2, QR code contains 3 detection patterns A, B, C with the same size and shape. 12 Tilt Correction • The detection pattern is posed of three overlapping concentric squares, the black and white of the module39。 s ratio is 1:1:3:1:1. • The width of each module allows deviation of . 13 Tilt Correction • Fig3. Rotation Correction • As shown in fig3, S square area is the original QR code image. • N square is the area after interception. • P1, P2, P3 are the three feature points. 14 Tilt Correction • Assuming the rotation angle is θ. • Calculate Strike distance between three points and find the longest distance, suppose it is P2,P3. 15 Tilt Correction • After the center coordinate of QR code determined, to capture its square on the image center to ensure the QR code can all access. • The length of the intercepted side is at least New Length = √2 * SourceLength * sinθ 16 Tilt Correction • Because the purpose of rotation coordinates is not necessarily integer coordinates, in order to ensure the image is not distorted, the gray value of purpose pixel needs for interpolation in the image rotation transformation. • The frequentlyused methods include the nearest neighbor interpolation, bilinear interpolation and trilinear interpolation. 1。