The metalnano wire grating is the core component of pixelated polarizing camera,and the micro-polarizer array engraved on the wire grating is one to one correspondence with the photodetector. This micro-polarizer array has high non-uniformity and large influence on image quality. Aiming at this problem, we improve the mathematic model of pixel-level vector transfer matrix measurement algorithm based on the structure of the nano wire grating and the polarization transfer theory. Combined with the matrix least squares algorithm, a number of measurements are established to fit the optimal transfer matrix algorithm, and then the core calibration parameters are provided for pixel-level non-uniform calibration of the polarization camera. Considering the structure of the nano wire grating, a calibration algorithm with high spatial resolution is proposed. The non-uniformity of polarization camera decreases from 2.00% to 0.26% after calibration. On the outfield experiment, the information entropy of the target polarization image rises from 5.34 to 15.15. The results show that the proposed algorithm can effectively correct the non-uniformity of the nano wire grating and improve the quality of polarization image.