Complex sentence: VC-1 is the informal name of the SMPTE 421M video codec standard, which was initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3,2006.
Split into simpler sentences: VC-1 is the informal name of the SMPTE 421M video codec standard. Initially developed as a proprietary video format by Microsoft before it was released as a formal SMPTE standard video format on April 3,2006.