1. A method, comprising: registering a new image volume with a composed image volume, wherein the new image volume and the composed image volume overlap each other in an overlap region, the composed image volume includes at least two image volumes that overlap each other, and each voxel in the composed image volume includes a weight; determining a deformation between the new image volume and the composed image volume; updating the weights of the voxels in the composed image volume that are overlapped by the new image volume; performing an alpha morphing on the overlap region using the updated weights and the deformation; obtaining a blend region of the overlap region by performing an alpha blending using results of the alpha morphing and the updated weights; and incorporating the blend region into the composed image volume to obtain a new composed image volume.