Why bother having an MPEG-2 ?
A. MPEG-1 was optimized for CD-ROM or applications at about 1.5 Mbit/sec. Video was strictly non-interlaced (i.e. progressive). The international cooperation executed well enough for MPEG-1, that the committee began to address applications at broadcast TV sample rates using the CCIR 601 recommendation (720 samples/line by 480 lines per frame by 30 frames per second or about 15.2 million samples/sec including chroma) as the reference. Unfortunately, today’s TV scanning pattern is interlaced. This introduces a duality in block coding: do local redundancy areas (blocks) exist exclusively in a field or a frame.(or a particle or wave) ? The answer of course is that some blocks are one or the other at different times, depending on motion activity. The additional man years of experimentation and implementation between MPEG-1 and MPEG-2 improved the method of block-based transform coding. It is often remarked that MPEG-2 spent several hundred man years and 10s of millions of dollars yet only g
