D-3 is an uncompressed composite digital video format invented at NHK and introduced commercially by Panasonic. It was launched in 1991 to compete with Ampex's D-2.
The D-3 format is now regarded as obsolete. In the early 1990s the BBC embarked on a massive project to copy its older video tapes onto D-3 for archival, but the D-3 cassettes themselves have become obsolete and are being transferred to modern digital video standards. There is doubt over whether the surviving D-3 machines will last long enough to play the 340,000 tapes which the corporation holds.