Corralling the Chaos of Ancillary Data within Multiple File Formats

摘要

The baseband Serial Digital Interface (SDI) workflows and formats were "iron clad" and well defined. These were the "good old days" when devices interconnected with ease thanks to the rigor and breadth of SMPTE standards for SDI. Nowadays, with the great flexibility of file based media workflows and the multitude of formats needed for different applications, the industry is dealing with incompatible wrappers and inconsistent or non-extendable Ancillary (ANC) data carriage. This paper will look at these evolving workflows and the resulting "Wild West" of files. More specifically, the paper explores the challenges faced with the handling of ANC data such as Active Format Descriptor (AFD), closed captions, ad insertion triggers, audio metadata, etc., within various file formats. The paper then describes the unified and extensible approach offered by SMPTE 436M for the carriage of ANC data within Material Exchange Format (MXF) wrapped files. Could SMPTE 436M be the champion the industry needs to restore order to the Wild West and corral some of the chaos?