关键词: 计算统一设备架构(CUDA), 尺度不变特征变换, 图像配准, 图像拼接

Abstract:

In order to overcome the characteristics of low contrast, non-uniform illumination, limited field of view (FOV), and the geometric distortion between different FOV of the fundus images, a fast automatic fundus image registration and mosaic algorithm was presented based on CUDA. Fundus images were enhanced by homomorphism filtering and the SIFT features in effective FOV were extracted and matched between images with CUDA speeded up. With CUDA application, point pairs were purified using RANSAC algorithm employed perspective model, transformation matrixes were computed according to the matching point pairs of surrounding FOV images to the central, image registration and image fusion was implemented to get fundus panoramic image finally. The automatic registration and mosaic results of multiple FOV images obtained by fundus camera show that the algorithm is robust and stability with registration accuracy is up to pixel level, the algorithm speed upgrades 10 to 30 times, high-precision automatic fundus image mosaic can be achieved.

Key words: compute unified device architecture(CUDA), scale invariant feature transform(SIFT), image registration, images mosaic