Tus naj npawb ntawm TVs nrog 4K zaub daws teeb meem tau tawg, thiab rau qhov laj thawj zoo. Leej twg tsis xav kom meej meej duab TV?
Ultra HD: Ntau dua li 4K daws teeb meem
Tus qauv daws teeb meem 4K yog ib feem ntawm qhov tam sim no hu ua Ultra HD. Ntxiv rau qhov kev daws teeb meem ntau ntxiv, qhov ci ntsa iab thiab qib raug raug yog qhov tseem ceeb uas txhim kho cov duab zoo vim yog cov teeb pom kev zoo ntxiv nrog rau kev ua yeeb yaj kiab hu ua HDR.
YHDR yog dab tsi?
HDR sawv rau High Dynamic Range.
Thaum lub sijhawm tsim cov txheej txheem rau cov ntsiab lus xaiv rau kev ua yeeb yaj kiab lossis kev nthuav qhia hauv tsev, qhov ci ntsa iab thiab qhov sib txawv ntawm cov ntaub ntawv uas tau ntes thaum lub sijhawm ua yeeb yaj kiab yog encoded rau hauv lub teeb liab video. Thaum cov ntsiab lus muab tso rau hauv cov kwj, tshaj tawm, lossis hauv ib lub disc, lub teeb liab raug xa mus rau HDR-enabled TV.
Cov ntaub ntawv raug txiav txim siab, thiab cov ntaub ntawv muaj zog ntau ntau qhia, raws li qhov ci ntsa iab thiab qhov sib txawv ntawm lub TV. Yog tias lub TV tsis yog HDR-enabled (hu ua tus qauv dynamic range TV), nws qhia cov dluab yam tsis muaj cov ntaub ntawv siab dynamic ntau.
Ntxiv rau qhov kev daws teeb meem 4K thiab cov xim dav dav, HDR-enabled TV, ua ke nrog cov ntsiab lus nkag tau zoo, tuaj yeem tso saib qhov ci thiab qhov sib txawv nyob ze rau qhov koj pom hauv lub ntiaj teb tiag. Qhov no txhais tau tias ci dawb tsis tawg los yog ntxuav tawm, thiab tob tob tsis muaj av nkos lossis crushing.
Piv txwv li, yog tias ib qho chaw muaj cov ntsiab lus ci thiab tsaus ntuj nyob rau hauv tib lub thav duab, xws li hnub poob, koj pom ob lub teeb ci ntawm lub hnub thiab qhov tsaus ntuj ntawm cov duab nrog sib npaug, nrog rau txhua qib brightness nyob nruab nrab ntawm.
Vim tias muaj ntau yam ntawm dawb mus rau xim dub, cov ntsiab lus tsis nquag pom nyob rau hauv ob qho tib si kaj thiab tsaus ntuj ntawm cov qauv TV duab tau yooj yim dua pom ntawm HDR-enabled TVs, uas muab kev txaus siab rau kev pom ntau dua.
Yuav ua li cas HDR cuam tshuam rau cov neeg siv khoom
HDR sawv cev rau cov kauj ruam hloov pauv hauv kev txhim kho kev pom TV. Txawm li cas los xij, cov neeg siv khoom ntsib plaub hom HDR tseem ceeb uas cuam tshuam rau TVs, cov khoom siv sib txuas, thiab cov ntsiab lus lawv yuav tsum yuav. Plaub hom no yog:
- HDR10
- Dolby Vision
- HLG (Hybrid Log Gamma)
- Technicolor HDR
Txhua hom ntawv muaj nws tus yam ntxwv tshwj xeeb.
HDR10 thiab HDR10+
HDR10 yog tus qauv qhib, tsis pub muaj nuj nqis koom nrog hauv txhua HDR-tshaj TVs, tus txais kev ua yeeb yam hauv tsev, Ultra HD Blu-duab tshav players, thiab xaiv cov xov xwm streamers.
HDR10 yog suav tias yog ntau dua, vim tias nws cov kev txwv tau siv sib npaug thoob plaws ib qho ntawm cov ntsiab lus. Piv txwv li, qhov nruab nrab qhov ci ci yog txiav txim siab thoob plaws ib zaj duab xis.
Thaum lub sijhawm tsim cov txheej txheem, lub teeb ci tshaj plaws thiab qhov tsaus ntuj tshaj plaws hauv cov yeeb yaj kiab raug cim. Thaum cov ntsiab lus HDR raug ntaus rov qab, tag nrho lwm cov qib ci ntsa iab raug ntsuas rau cov ntsiab lus ntawd.
Txawm li cas los xij, xyoo 2017, Samsung tau nthuav tawm qhov xwm txheej ntawm qhov xwm txheej mus rau HDR hu ua HDR10+ (tsis yog yuav tsum tsis meej pem nrog HDR+, uas yuav tau tham hauv qab no). Ib yam li HDR10, HDR10+ tsis muaj nuj nqis, tab sis muaj qee tus nqi pib siv.
Txawm hais tias txhua yam khoom siv HDR siv HDR10, TVs thiab cov ntsiab lus los ntawm Samsung, Panasonic, thiab 20th Century Fox siv HDR10 thiab HDR10+ nkaus xwb.
Dolby Vision
Dolby Vision yog HDR hom tsim thiab ua lag luam los ntawm Dolby Labs, uas sib txuas cov khoom siv thiab cov metadata hauv nws qhov kev siv. Qhov kev xav tau ntxiv yog cov neeg tsim cov ntsiab lus, cov chaw muab kev pabcuam, thiab cov tsim khoom siv yuav tsum tau them Dolby tus nqi ntawv tso cai rau nws siv.
Dolby Vision yog suav tias yog qhov tseeb dua li HDR10. Nws cov HDR tsis tuaj yeem raug encoded scene-los-scene lossis thav duab-los-nruab nrab thiab nws tuaj yeem ua si raws li lub peev xwm ntawm TV. Nyob rau hauv lwm yam lus, playback yog raws li nyob rau hauv lub brightness theem tam sim no ntawm ib tug muab kev taw qhia, xws li ib tug ncej los yog scene, es tsis txwv rau qhov siab tshaj plaws brightness theem rau tag nrho cov zaj duab xis.
Ntawm qhov tod tes, txoj kev Dolby tau teeb tsa Dolby Vision, txhua lub TV uas muaj ntawv tso cai thiab muaj peev xwm txhawb nqa hom ntawv tuaj yeem txiav txim siab HDR10 teeb liab yog tias cov chaw tsim khoom TV tau qhib lub peev xwm no. Txawm li cas los xij, lub TV uas tsuas yog ua raws HDR10 tsis muaj peev xwm txiav txim siab Dolby Vision signals.
Hauv lwm lo lus, Dolby Vision TV tuaj yeem txiav txim siab HDR10, thiab HDR10 nkaus xwb TV tsis tuaj yeem txiav txim siab Dolby Vision. Txawm li cas los xij, ntau tus neeg muab kev pabcuam uas suav nrog Dolby Vision encoding hauv lawv cov ntsiab lus feem ntau suav nrog HDR10 encoding, tshwj xeeb kom haum rau HDR-enabled TVs uas tej zaum yuav tsis sib haum nrog Dolby Vision.
Thaum cov ntsiab lus muaj xws li Dolby Vision nkaus xwb thiab TV yog HDR10 sib xws nkaus xwb, TV tsis quav ntsej Dolby Vision encoding thiab qhia cov duab raws li tus qauv dynamic ntau yam duab. Hauv lwm lo lus, qhov ntawd, koj yuav tsis tau txais txiaj ntsig ntawm HDR.
TV hom uas txhawb Dolby Vision suav nrog cov qauv xaiv los ntawm LG, Philips, Sony, TCL, thiab Vizio. Ultra HD Blu-duab tshav players uas txhawb Dolby Vision suav nrog xaiv cov qauv ntawm OPPO Digital, LG, Philips, Sony, Panasonic, thiab Cambridge Audio. Nyob ntawm cov cuab yeej tsim khoom hnub tim, Dolby Vision compatibility yuav tsuas qhib tom qab hloov tshiab firmware.
Ntawm cov ntsiab lus sab, Dolby Vision tau txais kev txhawb nqa los ntawm streaming ntawm cov ntsiab lus xaiv muaj nyob rau ntawm Netflix, Amazon, thiab Vudu, nrog rau qee qhov tsawg ntawm cov yeeb yaj kiab ntawm Ultra HD Blu-ray Disc.
Samsung yog tib lub npe TV loj uas ua lag luam hauv Asmeskas uas tsis txhawb Dolby Vision. Samsung TVs thiab Ultra HD Blu-duab tshav Disc players tsuas txhawb HDR10.
Hybrid Log Gamma (HLG)
Hybrid log gamma yog hom HDR uas tsim los rau kev tshaj tawm xov tooj cua, satellite, thiab tshaj tawm hauv TV. Nws tau tsim los ntawm Nyiv NHK thiab BBC Broadcasting Systems tab sis tsis muaj ntawv tso cai.
Qhov txiaj ntsig tseem ceeb ntawm HLG rau TV tshaj tawm thiab cov tswv yog qhov rov qab sib xws. Hauv lwm lo lus, txij li qhov chaw bandwidth yog tus nqi them rau TV tshaj tawm, siv HDR hom xws li HDR10 lossis Dolby Vision tsis tso cai rau cov tswv ntawm cov TV uas tsis yog HDR (xws li TV tsis yog HD) los saib cov ntsiab lus HDR-encoded.
Txawm li cas los xij, HLG encoding yog lwm qhov tshaj tawm xov xwm txheej, muaj cov ntaub ntawv ntxiv ci ntsa iab yam tsis xav tau cov ntaub ntawv tshwj xeeb, uas tuaj yeem muab tso rau saum cov teeb liab TV tam sim no. Yog li ntawd, cov duab tuaj yeem pom ntawm txhua lub TV.
Yog tias koj tsis muaj HLG-enabled HDR TV, nws yuav tsis paub txog cov txheej txheem HDR ntxiv, yog li koj yuav tsis tau txais txiaj ntsig ntawm kev ua ntxiv, tab sis koj yuav tau txais cov duab SDR txheem.
Txawm hais tias HLG muab txoj hauv kev rau SDR thiab HDR TVs kom sib haum nrog tib lub xov tooj cua tshaj tawm, nws tsis muab qhov tseeb HDR tshwm sim yog tias saib tib cov ntsiab lus nrog HDR10 lossis Dolby Vision encoding, txo qis HLG's muaj peev xwm.
HLG compatibility yog suav nrog rau feem ntau 4K Ultra HD HDR-enabled TVs (tshwj tsis yog Samsung qauv) thiab tsev ua yeeb yam txais tos pib xyoo 2017 qauv. Txog tam sim no, BBC thiab DirecTV tau muab qee qhov kev pab cuam siv HLG.
Technicolor HDR
Ntawm plaub hom HDR loj, Technicolor HDR yog qhov paub tsawg tshaj plaws thiab tsuas yog pom me me siv hauv Tebchaws Europe. Yog tsis tau bogged nyob rau hauv cov ntsiab lus kev, Technicolor HDR yog tej zaum qhov hloov tau yooj yim tshaj plaws, raws li nws yuav siv tau nyob rau hauv ob qho tib si kaw (streaming thiab disc) thiab tshaj tawm TV daim ntawv thov. Nws kuj tseem tuaj yeem raug encoded siv cov ntsiab lus-by-frame siv.
Ntxiv rau, zoo ib yam li HLG, Technicolor HDR rov qab siv tau nrog HDR thiab SDR-enabled TVs. Koj tau txais kev pom zoo tshaj plaws ntawm HDR TV, tab sis SDR TV tuaj yeem tau txais txiaj ntsig los ntawm kev ua kom zoo, raws li nws cov xim, qhov sib txawv, thiab lub peev xwm ci ntsa iab.
Technicolor HDR cov teeb liab tuaj yeem pom hauv SDR, ua kom yooj yim rau cov neeg tsim cov ntsiab lus, cov neeg muab cov ntsiab lus, thiab cov neeg saib TV. Technicolor HDR yog tus qauv qhib uas tsis muaj nuj nqis rau cov neeg muab khoom thiab TV tsim los siv.
Tone Mapping
Ib qho ntawm cov teeb meem hauv kev siv ntau hom HDR ntawm TVs yog tias tsis yog txhua lub TV muaj tib lub teeb pom kev zoo. Piv txwv li, lub high-end HDR-enabled TV yuav tso zis ntau npaum li 1,000 nits ntawm lub teeb (xws li ib co high-end LED / LCD TVs). Lwm tus yuav muaj qhov siab tshaj plaws ntawm 600 lossis 700 nits lub teeb tso zis (OLED thiab nruab nrab-ntau LED / LCD TVs). Thiab, qee tus nqi qis dua HDR-enabled LED / LCD TVs tsuas yog tso tawm txog 500 nits.
Vim li ntawd, cov txheej txheem hu ua tone mapping yog siv los daws qhov sib txawv no. Yuav ua li cas tshwm sim yog tias cov metadata muab tso rau hauv ib qho yeeb yaj kiab tshwj xeeb lossis cov kev pab cuam tau rov ua dua rau TV lub peev xwm. Qhov ci ntsa iab ntawm TV yog muab rau hauv kev txiav txim siab. Kev hloov kho yog ua rau lub siab tshaj plaws ci ntsa iab thiab tag nrho cov ntaub ntawv nruab nrab ntawm qhov ci ntsa iab, ua ke nrog cov ntsiab lus thiab xim tam sim no nyob rau hauv thawj metadata nyob rau hauv relation mus rau ntau yam ntawm TV. Yog li ntawd, lub siab tshaj plaws brightness encoded nyob rau hauv cov metadata yog tsis ntxuav tawm thaum pom nyob rau hauv lub TV nrog tsawg lub teeb-tso peev xwm.
SDR-rau-HDR Kev nce qib
Vim tias muaj cov ntsiab lus HDR-encoded tsis muaj ntau, ntau lub tuam txhab TV tau ua kom cov neeg siv nyiaj ntxiv siv rau HDR-enabled TV tsis mus pov tseg los ntawm suav nrog SDR-rau-HDR hloov dua siab tshiab. Samsung sau lawv cov kab ke ua HDR + (tsis yog yuav tsum tsis meej pem nrog HDR10+ tau tham ua ntej), thiab Technicolor sau nws cov kab ke ua Kev Txawj Ntse Tone Management.
Txawm li cas los xij, ib yam li nrog kev daws teeb meem nce ntxiv thiab 2D-rau-3D hloov dua siab tshiab, HDR + thiab SD-rau-HDR hloov dua siab tshiab tsis muab qhov tseeb raws li cov ntsiab lus HDR ntuj. Qee cov ntsiab lus yuav zoo li ntxuav tawm lossis tsis sib npaug ntawm qhov chaw mus rau qhov chaw, tab sis nws muab lwm txoj hauv kev los ua kom zoo dua HDR-enabled TV lub peev xwm ci ntsa iab. HDR + thiab SDR-rau-HDR hloov dua siab tshiab tuaj yeem qhib lossis tawm raws li qhov xav tau. SDR-rau-HDR upscaling tseem hu ua inverse tone mapping.
Ntxiv rau SD-rau-HDR kev nce qib, LG suav nrog lub kaw lus nws hais txog kev ua haujlwm HDR rau hauv ib qho kev xaiv ntawm nws cov HDR-enabled TVs, uas ntxiv onboard scene-by-scene brightness tsom rau ob HDR10 thiab HLG cov ntsiab lus, txhim kho qhov tseeb ntawm ob hom ntawv.
Samsung's HDR+ kho qhov ci thiab qhov sib piv ntawm HDR10 encoded cov ntsiab lus kom cov khoom sib txawv ntau dua.
Txoj kab hauv qab
Qhov sib ntxiv ntawm HDR txhawb nqa kev pom TV. Raws li qhov sib txawv ntawm hom tau raug daws, thiab cov ntsiab lus tau dav dav thoob plaws hauv daim disk, streaming, thiab tshaj tawm, cov neeg siv khoom yuav zoo siab txais nws ib yam li lawv tau ua dhau los.
Txawm hais tias HDR tsuas yog siv ua ke nrog 4K Ultra HD cov ntsiab lus, thev naus laus zis tsis muaj kev daws teeb meem. Qhov no txhais tau hais tias nws tuaj yeem siv rau lwm qhov kev daws teeb meem video, txawm tias nws yog 480p, 720p, 1080i, lossis 1080p. Qhov no kuj txhais tau tias muaj 4K Ultra HD TV tsis tau txhais hais tias nws yog HDR-tshaj. Tus tsim TV tau txiav txim siab lees paub suav nrog nws.
Txawm li cas los xij, qhov tseem ceeb los ntawm cov neeg tsim cov ntsiab lus thiab cov neeg muab kev pabcuam tau siv HDR peev xwm hauv 4K Ultra HD platform. Nrog rau cov uas tsis yog-4K ultra HD TVs, DVD, thiab tus qauv Blu-duab tshav disc players ploj zuj zus, thiab nrog rau kev nplua nuj ntawm 4K Ultra HD TVs nrog rau ntau ntxiv ntawm Ultra HD Blu-duab tshav players muaj, nrog rau yav tom ntej. Kev siv ATSC 3.0 TV tshaj tawm, lub sijhawm thiab nyiaj txiag peev ntawm HDR thev naus laus zis yog qhov zoo tshaj plaws rau kev ua kom muaj nuj nqis ntawm 4K Ultra HD cov ntsiab lus, cov khoom siv, thiab TVs.
Txawm hais tias nyob rau hauv nws qhov kev siv tam sim no zoo li muaj ntau qhov tsis meej pem, nws yuav txheeb tawm thaum kawg. Txawm hais tias muaj qhov sib txawv me ntsis ntawm txhua hom ntawv (Dolby Vision yog suav tias muaj qhov me me), txhua hom HDR muab kev txhim kho tseem ceeb hauv kev saib TV.
FAQ
HDR10 txawv ntawm HDR10+ li cas?
HDR10 yog tus qauv qub, thiab HDR10+ yog tus ua tiav rau HDR10 tus qauv. Txawm li cas los xij, koj lub TV tshwj xeeb thiab nws qhov kev siv HDR tshwj xeeb yuav txiav txim siab seb koj qhov kev paub HDR zoo npaum li cas.
Puas tseem ceeb dua kom muaj HDR lossis 4K?
HDR thiab 4K yog cov thev naus laus zis sib txawv. HDR suav nrog qhov ci ntsa iab thiab qhov sib piv ntawm cov zaub, thaum 4K hais txog cov zaub daws teeb meem. Cov kev daws teeb meem siab dua thiab HDR ob leeg muab lawv tus kheej zoo.
