In 1994-1995, all the pieces for digital cinema were there, but they weren't integrated, and there were no installed projectors. The Phantom Menance was shown digitally.... on two screens. By the end of 2000, there were 31 digital cinema screens in theaters.
Digital cinema went with Motion JPEG2000 with high quality settings, which leads to very large files, but also much better fidelity than likely with a contemporary video codec.