Aiming at the problem of large scene, large field of view image applications and the slow speed of traditional image stitching algorithms, a fast image stitching algorithm based on offline calibration is adopted. In practical applications, the positions of multiple cameras are fixed, and offline calibration is used to calculate the homography matrix of image-stitching, which saves a lot of feature extraction and registration time. On the basis of fast image alignment, a fast image fusion algorithm based on the Laplacian pyramid of YUV color space is proposed in this paper, and it has better fusion effect and faster speed than the traditional Laplacian pyramid fusion algorithm. Experimental results show that the image fusion speed of the article algorithm is three times that of traditional Laplacian image fusion. The alorithm of this paper can meet the real-time image stitching speed requirements in application scenarios, with good image stitching effects.