What are MPEG-2 VIDEO Main Profile and Main Level ?
MPEG-2 Video Main Level is analogous to MPEG-1’s CPB, with sampling limits at CCIR-610 parameters (720 x 480 x 30 Hz). Profiles limit syntax (i.e. algorithms), whereas Levels limit parameters (sample rates, frame dimensions, coded bitrates, etc.). Together, Video Main Profile and Main Level (abbreviated as MP@ML) normalize complexity within feasible limits of 1994 VLSI technology (0.5 micron), yet still meet the needs of the majority of application users.
It is inappropriate to talk about MPEG-2 profiles without also talking about levels. The 4 profiles define the colorspace resolution, and scalability of the bitstream. The levels define the maximum and minumum for image resolution, and Y (Luminance) samples per second, the number of video and audio layers supported for scalable profiles, and the maximum bit rate per profile. The combination of a profile and a level produces an architecture which defines the ability of a decoder to handle a particular bitstream. MPEG-2 Video Main Level is analogous to MPEG-1’s CPB, with sampling limits at CCIR-601 parameters (720 x 480 x 30 Hz). Profiles limit syntax (i.e. algorithms), whereas Levels limit parameters (sample rates, frame dimensions, coded bitrates, etc.). Together, Video Main Profile and Main Level (abbreviated as MP@ML) normalize complexity within feasible limits of 1994 VLSI technology (0.5 micron), yet still meet the needs of the majority of application users.
