▁ ▁Sp atial ▁It ▁predict s ▁the ▁movement ▁from ▁neighbour ▁macro block s ▁in ▁same ▁frame . ▁A ▁possible ▁criter ion ▁could ▁be ▁to ▁copy ▁the ▁motion ▁vector ▁from ▁a ▁neighbor ing ▁block . ▁These ▁modes ▁are ▁used ▁in ▁uniform ▁zones ▁of ▁the ▁picture ▁where ▁there ▁is ▁not ▁much ▁movement . ▁ ▁In ▁the ▁figure ▁above , ▁p ink ▁blocks ▁are ▁Direct / Sk ip ▁Mode ▁c oded ▁blocks . ▁As ▁we ▁can ▁see , ▁they ▁are ▁used ▁very ▁frequently , ▁mainly ▁in ▁B - frames . ▁ ▁Add itional ▁information ▁Although ▁the ▁use ▁of ▁the ▁term ▁" frame " ▁is ▁common ▁in ▁inform al ▁usage , ▁in ▁many ▁cases ▁( such ▁as ▁in ▁international ▁standards ▁for ▁video ▁coding ▁by ▁M PE G ▁and ▁V CE G ) ▁a ▁more ▁general ▁concept ▁is ▁applied ▁by ▁using ▁the ▁word ▁" picture " ▁rather ▁than ▁" frame ", ▁where ▁a ▁picture ▁can ▁either ▁be ▁a ▁complete ▁frame ▁or ▁a ▁single ▁inter la ced ▁field . ▁ ▁Video ▁code cs ▁such ▁as ▁M PE G - 2 , ▁H . 2 6 4 ▁or ▁O gg ▁The ora ▁reduce ▁the ▁amount ▁of ▁data ▁in ▁a ▁stream ▁by ▁following ▁key ▁frames ▁with ▁one ▁or ▁more ▁inter ▁frames . ▁ ▁These ▁frames ▁can ▁typically ▁be ▁encoded ▁using ▁a ▁lower ▁bit ▁rate ▁than ▁is ▁needed ▁for ▁key ▁frames ▁because ▁much ▁of ▁the ▁image ▁is ▁ordin arily ▁similar , ▁so ▁only ▁the ▁changing ▁parts ▁need ▁to ▁be ▁c oded . ▁ ▁See ▁also ▁Video ▁compression ▁picture ▁types ▁ ▁References ▁▁▁