A method of interpolating positron emission tomography (PET) data for reconstructing a PET image, including acquiring PET event data, which was obtained by scanning an object using a PET scanner; generating a two-dimensional line-of-response (LOR) sinogram from the acquired PET event data; determining a plurality of triangles connecting sampling points within the LOR sinogram, wherein adjacent sampling points are connected horizontally row-by-row within the LOR sinogram to determine the plurality of triangles; and determining a uniformly sampled sinogram from the LOR sinogram using the determined plurality of triangles.