What Chroma Format that has both Picture Coding Types of i, p, b, and the Name of main profile?
CREATE TABLE "mpeg_2_profiles" (
  "abbr" text,
  "name" text,
  "picture_coding_types" text,
  "chroma_format" text,
  "aspect_ratios" text,
  "scalable_modes" text,
  "intra_dc_precision" text
);
SELECT "chroma_format" FROM "mpeg_2_profiles" WHERE "picture_coding_types"='i, p, b' AND "name"='main profile';