SMPTE EG 40-2002

This guideline specifies a set of formulas for converting between SMPTE 12M time code, MPEG-2 systems layer program clock reference (PCR) time base, and absolute time. Included are formulas for converting SMPTE 12M time address values and MPEG-2 PCR time base values to absolute time, and formulas for converting SMPTE 12M time address values directly to/from MPEG-2 PCR time base values. Absolute time conversion formulas may be useful for converting between different frame rates of SMPTE 12M time code; e.g., a 24-fps SMPTE time code running at 23.976 fps could be converted to true time and then to a 29.97 drop frame SMPTE time code value.