The　AVS　video　coding　schemes,　which　is　developed　by　china,　uses　a　different　transform　(ICT)　than　before.　The　recently　completed　video　coding　standard,　H.264/AVC,　also　uses　an　integer　transform,　(HT).　In　this　paper,　we　propose　an　efficient　method　to　convert　ICT　coefficients　to　HT　coefficients　entirely　in　the　transform　domain.　We　show　that　the　conversion　is　essentially　a　2D　transform.　We　derive　the　transform　kernel　matrix　and　provide　a　fast　algorithm.　We　show　that　the　proposed　transform　domain　conversion　outperforms　the　conventional　pixel　domain　approach.　It　is　expected　to　have　applications　in　transform　domain　video　transcoding.