1. c im

D on khng gian nh hng trong kiu m ha Intra: h tr ti 17 kiu d on, lm cho vic d on mu c chnh xc hn, t hiu qu nn cao hn.

B chuyn ng vi kch thc nh c th thay i. Tiu chun ny mang li s mm do cho s la chn kch thc v hnh dng, kch thc b chuyn ng nh nht l 4x4. iu ny mang li hiu sut 15% so vi MPEG-2. B chuyn ng lm gim tnh phc tp ca x l ni suy so vi cc tiu chun trc .

B chuyn ng vi nhiu hnh tham kho. Do camera thay i gc quay hay chuyn qua li gia cc cnh, vic on trc cc chuyn ng l rt phc tp ta cn phi c nhiu frame tham kho nng cao hiu sut v cht lng. H.264/AVC cho php s dng ti a 32 frametham kho trong khi MPEG-2 ch s dng 2 frame tham kho mang tnh cht chu k. B chuyn ng vi nhiu hnh tham kho s l chm qu trnh m ha v gii m nhng s tng cht lng nh vi cng t s nn.

Tch ring hnh tham kho v hnh hin th: cc tiu chun trc c s ph thuc gia hnh tham kho v hnh hin th, cn trong H.264/AVC b m ha c th chn hnh nh tham kho gn nht vi hnh nh c m ha cho mc ch tham kho d on nn c th hin th vi tnh linh hot cao, do khong thi gian tr s c loi b.

Gim d tha v khng gian tt hn: s dng php bin i nguyn thay v s dng php bin i DCT nh MPEG-2, lm gim nh hng do sai s lm trn.

Lng t ha thch nghi: trong qu trnh m ha vi tc bit bin thin, khi s dng lng t ha thch nghi, mi frame c th c nn vi nhng b lng t khc nhau ph thuc vo bn cht hnh nh ca chng thng qua vic iu khin tc bit. V d nhng phn chuyn ng hay nhng phn hnh nh sm mu kh nhn bit s c x l vi h s lng t ln hn ( nn cao hn, dung lng nh hn), nhng phn hay c h thng mt ngi ch nhiu hn s c x l vi h s lng t thp hn ( nn nh hn, dung lng ln hn). H.264/AVC cho php s dng ti 52 mc lng t trong khi MPEG-2 ch c 31 mc.

S dng b lc tch khi: Tri ngc vi b tin x l hay b hu x l, b lc tch khi c p dng trong sut qu trnh m ha trn mi frame n l, nhng trc n s c s dng tham kho cho nhng frame n sau. Ci tin mi ny s gip trnh c hin tng kt khi lm nh hng n cht lng hnh nh, c bit l vi tc bit thp. Nhng tc m ha, gii m s b gim st. Kiu d on trng s.H.264/AVC c th h tr qu trnh m dn hay ti dn khung hnh trong nhng on film c hiu ng m dn (nhng frame n sau rt ging so vi nhng frame ngay trc n, ch c sc l khc mt cht),.

M ha Entropy thch nghi: trong H.264/AVC s dng 2 phng php m ha phc tp hn l CAVLC v CABAC thay v bin i VCL tnh trong MPEG-2, nn hiu qu m ha cng cao hn r rt.

Mt s c tnh lm tng cng kh nng chng sai s v mt d liu nh :

Thng s ci t cu trc: tp hp cc thng s nhm tng cng cho thng tin u mc ca qu trnh truyn c hiu qu hn. nhng tiu chun trc, nu mt mt s thng tin quan trng nh thng tin u mc ca chui nh s nh hng rt ln n qu trnh gii m. Cn trong H.264/AVC th cc thng tin ny c tch ring to tnh linh hot v chuyn dng hn.