10.8 MPEG-2 MP@ML and SP@ML additional restrictions

Most of the restrictions for main profile at main level have been identified in the data elements code tables. However, there are some additional constraints. Table 10.27 gives the maximum number of bits in a macroblock. for the chrominance formats. At most two macroblocks in a macroblock row may exceed these values. The bits for the macroblock are counted from the first macroblock_escape or macroblock_address_increment to the last bit of the end-of-block code (or to the coded_block_pattern() if all blocks are skipped). The slice information is not counted as part of the macroblock.

In addition, Figure 10.26 gives additional constraints for MP@ML and SP@ML.

if ((vertical_size < 480)  (frame_rate==`0011')) {                                 /* if wide image or 25 Hz    */ if (picture_coding_type==3)     /* and if B-picture          */     repeat_first_field=*0;      /* can't repeat first field  */}                         ...