MPEG-2, MPEG-3, and MPEG-4

• MPEG-2 target applications

        
  -------------------------------------------------------------------
  Level        size     Pixels/sec   bit-rate      Application   
                                              (Mbits) 
  --------------------------------------------------------------------
  Low         352 x 240       3 M         4        consumer tape equiv.
  Main        720 x 480      10 M        15        studio TV       
  High 1440  1440 x 1152     47 M        60        consumer HDTV   
  High       1920 x 1080     63 M        80        film production      
  --------------------------------------------------------------------
  

• Differences from MPEG-1

  1.

  Search on fields, not just frames.

  2.

  4:2:2 and 4:4:4 macroblocks

  3.

  Frame sizes as large as 16383 x 16383

  4.

  Scalable modes: Temporal, Progressive,...

  5.

  Non-linear macroblock quantization factor

  6.

  A bunch of minor fixes (see MPEG FAQ for more details)

• MPEG-3: Originally for HDTV (1920 x 1080), got folded into MPEG-2

• MPEG-4: Originally targeted at very low bit-rate communication (4.8 to 64 kb/sec). Now addressing video processing...