Grayscale txhais li cas rau LED Zaub
Hauv cov duab digital, greyscale yog hais txog tus naj npawb ntawm cov qib sib txawv uas cov zaub tuaj yeem tsim rau txhua qhov xim channel. 8-ntsis greyscale system tsim 256 qib ib channel; 16-ntsis system tsim 65,536. Nyob rau hauv ib qho LED zaub, qhov no txhais ncaj qha mus rau pes tsawg kauj ruam nyob nruab nrab ntawm qhov tsaus ntuj tshaj plaws thiab lub brightest lub xeev ntawm ib tug LED.
Thaum greyscale qhov tob tsis txaus, cov tonal smooth gradations-xws li lub hnub poob saum ntuj los yog tib neeg lub ntsej muag yees duab nyob rau hauv lub teeb mos- yog rendered raws li pom bands los yog cov kauj ruam es tsis tas yuav hloov mus. Cov khoom qub no hu uabandinglos yogposterization, thiab nws yog qhov pom tseeb tshaj plaws nyob rau hauv qis - thaj tsam ci ntsa iab ntawm daim duab uas cov kauj ruam ntawm cov qib grayscale nyob ib sab yog perceptually loj.
Yuav Siv Grayscale li cas: PWM thiab Kev Tswj Tam Sim No
LED qhia siv ob txoj hauv kev los tswj qhov ci ntsa iab ib pixel, thiab cov txheej txheem no ncaj qha txiav txim siab qhov txiaj ntsig greyscale ntau yam:
Pulse Width Modulation (PWM).
PWM tswj kev ci ntsa iab ntawm LED los ntawm kev hloov lub LED rau thiab tawm ntawm qhov ntau zaus. Qhov piv ntawm ntawm - sij hawm mus rau tawm - lub sij hawm nyob rau hauv txhua lub voj voog txiav txim pom qhov kaj. Lub sijhawm ntev dua ntawm - lub sijhawm ua kom muaj qhov ci ntau dua; luv dua ntawm - lub sijhawm ua kom qis qis dua. Qhov tob grayscale nyob rau hauv PWM-raws li systems yog txiav txim los ntawm pes tsawg subdivisions muaj nyob rau hauv ib lub voj voog -ntau subdivisions txhais tau tias finer grayscale cov kauj ruam.
Qhov cuam tshuam tseem ceeb ntawm PWM yog flicker. Yog tias PWM zaus tsawg dhau lawm, qhov ceev ntawm -off switching yuav pom tau rau tib neeg lub qhov muag lossis rau cov koob yees duab, uas tshwm sim li dov cov kab tsaus nti hauv video footage. Qhov no yog vim li cas siab refresh npaum li cas (feem ntau 3,840 Hz lossis siab dua) yog ze rau kev ua haujlwm greyscale hauv cov ntawv thov kev tshaj lij. Ob qhov kev txwv tsis yog ywj siab-qhov tob dua grey nplai ntawm qhov muab tus nqi tshiab yuav tsum tau tsav ICs sai dua thiab ua haujlwm ntau dua.
Kev tswj tam sim no (Constant Current).
Lwm txoj hauv kev los yog lwm txoj hauv kev yog hloov qhov loj ntawm qhov tsav tam sim no es tsis yog lub voj voog ua haujlwm. Tsawg tam sim no ua dimmer tso zis; siab dua tam sim no ua kom cov zis ntau dua. Hauv kev xyaum, feem ntau LED cov tshuab ua ke ua ke ob txoj hauv kev: coarse brightness tswj ntawm qhov chaw tam sim no, thiab nplua greyscale cov kauj ruam ntawm PWM hauv qhov tam sim no. Qhov no hybrid mus kom ze txuas ntxiv qhov ua tau zoo grayscale ntau thaum ua kom PWM zaus siab txaus kom tsis txhob flicker.
Lub Gamma Curve thiab Nws Lub Luag Haujlwm hauv Pom Greyscale
Greyscale hauv LED zaub tsis yog tsuas yog hais txog kev muaj ntau cov kauj ruam - nws kuj yog hais txog yuav ua li cas cov kauj ruam no tau muab faib rau tib neeg kev nkag siab. Tib neeg kev pom qhov system tsis teb linearly rau kev hloov hauv lub teeb siv. Peb muaj kev nkag siab ntau dua rau qhov sib txawv ntawm cov tones tsaus dua li qhov kaj.
Vim li no, LED cov tshuab ua haujlwm siv lub gamma kho nkhaus thaum daim ntawv qhia cov teeb liab qhov tseem ceeb rau qhov tseeb LED tso zis ntau ntau. Ib qho gamma tus nqi ntawm 2.2 txhais tau hais tias cov zaub concentrates ntau dua greyscale cov kauj ruam nyob rau hauv qhov tsaus ntuj nti ntawm lub tonal ntau, txuam qhov rhiab heev ntawm tib neeg lub zeem muag. Yog tsis muaj kev kho gamma, cov duab yuav tshwm sim ntxuav tawm hauv qhov tseem ceeb thiab compressed hauv duab ntxoov ntxoo.
Kev nkag siab txog qhov teeb tsa gamma yuav yog qhov tshwj xeeb tshaj yog thaum siv cov khoom siv nrog cov neeg siv xov xwm tshwj xeeb lossis cov ntsiab lus tswj hwm. Kev tsis sib haum xeeb ntawm gamma ntawm qhov chaw thiab cov zaub tuaj yeem ua rau cov duab tshwm tsaus nti lossis tsis muaj duab ntxoov ntxoo nthuav dav, txawm tias ob lub cuab yeej raug ntsuas tus kheej kom raug.
Tsawg-Grayscale Performance: Qhov Teeb Meem Tsaus Kawg
Ib qho ntawm cov txheej txheem nyuaj tshaj plaws ntawm greyscale nyob rau hauv LED zaub yog tswj kom du gradations ntawm qhov tsawg kawg nkaus ntawm qhov ci ci. Thaum cov zaub yuav tsum tau qhia ze rau - cov ntsiab lus dub - lub teeb ci ntsa iab hauv qab, lossis xinesmas -style logo nthuav tawm- qhov txawv ntawm greyscale qib 1 thiab qib 0 (tag nrho tawm) tuaj yeem pom qhov loj yog tias cov khoom siv tsis muaj qhov tob me ntsis.
Qee cov tuam ntxhab hais qhov no los ntawm cov txheej txheem xws li:
- Virtual ntsis qhov tob expansion: Ua cov algorithms uas dither ntawm qhov nyob ib sab grayscale theem hla ntau thav ntawv, zoo simulating finer cov kauj ruam dua cov kho vajtse ib leeg yuav ua tau.
- Tsawg-Grayscale tam sim no them nyiaj: Kho cov tsav tam sim no tshwj xeeb ntawm qhov qis kawg ntawm qhov greyscale ntau kom ua rau cov kauj ruam me me zoo ib yam thiab perceptually uniform.
Cov txheej txheem no yog siv los ntawm tus tsav tsheb IC thiab tau txais daim npav, thiab lawv qhov zoo sib txawv ntawm cov neeg muag khoom. Thaum ntsuam xyuas cov zaub rau cov ntawv thov uas yuav tsum tau txuas ntxiv cov suab tsaus nti- tshaj tawm studios, simulation ib puag ncig, siab -kawg muag- nws tsim nyog thov cov khoom ua qauv qhia tshwj xeeb tsim los qhia qis -grayscale kev ua tau zoo.
Cov kev cuam tshuam los ntawm Daim Ntawv Thov
Cov kev cai greyscale ntawm ib qho zaub nyob ntawm qhov nws xav siv:
| Daim ntawv thov | Greyscale qhov tseem ceeb | Sau ntawv |
|---|---|---|
| Sab nraum zoov advertising billboard | Nruab nrab | Pom nyob rau hauv siab ambient teeb; subtle gradations tsawg pom nyob deb |
| Cov khw muag khoom sab hauv tsev lossis cov khoom lag luam | Siab | Kev saib ze ze ua kom pom cov duab kos duab |
| Tshaj tawm / TV studio backdrop | Siab heev | Lub koob yees duab capture amplifies tej banding; yuav tsum tau siab me ntsis tob thiab ruaj khov gamma |
| Rental stage / concert siv | Siab | Cov xwm txheej tsaus nti thiab cov teeb pom kev zoo hloov pauv yuav tsum muaj qhov qis qis - kawg greyscale |
| Tswj chav / saib xyuas phab ntsa | Siab heev | Cov ntsiab lus analytical yuav tsum raug tonal reproduction |
Yuav Ua Li Cas Xyuas Hauv Specifications
Thaum tshuaj xyuas LED cov ntaub ntawv cov ntaub ntawv lossis thov cov ntaub ntawv xov xwm los ntawm tus neeg muag khoom, cov ntsiab lus hauv qab no cuam tshuam ncaj qha rau kev ua haujlwm grey:
- Greyscale qib: Nrhiav qhov tob me ntsis rau ib channel (xws li, 16-ntsis ua, 65,536 qib). Nco ntsoov tias "kev ua qhov tob me ntsis" thiab "lub cev me ntsis qhov tob" yuav txawv -qee lub tshuab ua cov txheej txheem 8-ntsis input teeb liab sab hauv.
- Refresh tus nqi: Cov nqi tshiab siab dua feem ntau txhawb kev ua haujlwm zoo dua qub los ntawm kev txo cov kev lag luam tawm - tawm ntawm PWM zaus thiab kev daws teeb meem grey.
- Gamma xaiv: Paub meej tias cov zaub txhawb kev hloov kho gamma, thiab seb nws puas tuaj yeem phim rau koj cov ntsiab lus.
- Tsawg-cov ntaub ntawv ua haujlwm grey: Nug seb tus neeg muag khoom puas tuaj yeem muab cov ntaub ntawv greyscale linearity los yog kev ua qauv qhia nyob ntawm qhov qis qis.
Cov ntsiab lus
Grayscale qhov tob yog ib qho kev txiav txim siab ntawm cov duab zoo uas ua haujlwm hauv qab ntawm qhov pom pom ntau dua. Tsis txaus greyscale ua rau cov khoom siv banding, cov duab ntxoov ntxoo tsis zoo, thiab flicker uas cuam tshuam rau ob tus neeg saib thiab lub koob yees duab. Kev siv cov txuj ci-PWM zaus, kev tswj tam sim no, tsav tsheb IC qhov tob, kev ua haujlwm gamma- sib txawv ntawm cov khoom lag luam thiab cuam tshuam ncaj qha li cas cov zaub ua tau zoo hauv qhov xav tau qhov chaw pom. Kev ntsuam xyuas greyscale nrog rau qhov ci thiab pixel suab muab cov duab ua tiav ntau dua ntawm cov peev xwm tso saib.